Single circuit to dual circuit
Todd
Posted 2020-08-02 10:22 AM (#601590)
Subject: Single circuit to dual circuit



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hi folks.
My current single circuit master brake cylinder has a 1/4 "line to the front tee. All other lines have only 3/16". Now I would like to convert to a dual circuit brake system. Does one line from the Dual master cylinder have to be thicker here too, or can both lines coming out of the dual circuit master cylinder also have 3/16 "?
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58coupe
Posted 2020-08-02 11:28 AM (#601593 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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The reason the front line is 1/4" is because you are feeding 4 wheel cylinders, 2 on each wheel. The rear is only 1 wheel cylinder on each side. What are you changing, just the master cylinder?
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Todd
Posted 2020-08-02 1:17 PM (#601599 - in reply to #601593)
Subject: Re: Single circuit to dual circuit



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Hi. Thanks for reply. I want to change the master brake cylinder (single to dual) and all brake lines.
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Powerflite
Posted 2020-08-02 8:26 PM (#601616 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I use a special 1/4 type (forgot the thread size) of tube nut on a 3/16 line at the top and block off the rear port.
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71charger_fan
Posted 2020-08-02 9:53 PM (#601621 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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You can get a 25' coil of copper nickel brake line with an assortment of fittings off of Ebay for less than $30. I wound up buying the Eastwood on car flaring tool and was very pleased with how well it worked.
https://www.eastwood.com/eastwood-on-car-flaring-tool-for-3-16-tubin...

http://www.forwardlook.net/forums/forums/thread-view.asp?tid=63722&...

Edited by 71charger_fan 2020-08-02 10:15 PM
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51coronet
Posted 2020-08-04 8:59 AM (#601678 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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Best flaring tool I have used so far is ridgid
https://www.amazon.com/RIDGID-83037-Precision-Ratcheting-Flaring/dp/...

It is nearly automatic, makes perfect flares each time, can do stainless line easily, not very expensive considering how well it works. You cant lose either piece with how its permanently attached to each other which is weird for me since I have used the dual piece ones for 20+ years. It just works well. Very nice tool. It moves in an orbital motion which flares line very nice. Old ones just pressed into the hole and relied on the tool to hold it without the tube slipping downward. Moving in a small orbit is the proper way to flare lines.
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Todd
Posted 2020-09-08 12:23 PM (#603021 - in reply to #601678)
Subject: Re: Single circuit to dual circuit



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This is the bendix style master cylinder i want to use for the conversion:

[img]https://thumbs.picr.de/39393590af.jpg[/img]

I'm unsure with the ports. The right/first port on that picture is 1/2"-20 INV as primary and the left/second port on the pic is 9/16"-20 INV as secondary.
The smaller Primary port (right on pic) feeds the two front lines (goes into the tee) and the bigger secondary (left on pic) feeds the line to reward, am i right?

And...do i have to use a 1/4" line from primary port to the FL tee? (as it actually is at my single cirq. master)
And all other lines 3/16?

Edited by Todd 2020-09-08 12:30 PM
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Powerflite
Posted 2020-09-08 12:45 PM (#603024 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes, that is correct that the front port of the master feeds the rear brakes. Chrysler ported them backwards for some reason.
Also, read my post above. I don't use a 1/4" line. Use a 3/16" line with a special tube nut that fits the larger port. The thread size is 7/16-24 like these on ebay.

https://www.ebay.com/itm/7-16-24-Inverted-Flare-3-16-Tube-Zinc-Nut-B...

Also, make sure you get the correct 9/16-20 Chrysler tube nut. GM uses a more common 9/16-18 tube nut that won't work.

Edited by Powerflite 2020-09-08 12:47 PM
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Todd
Posted 2020-09-08 1:15 PM (#603026 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Great support, thanks a lot!! This is good to know. Thank you very much for the infos
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Todd
Posted 2020-09-09 1:03 PM (#603057 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Does anyone know if the push rod of the single master will fit to the dual bendix ?

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Powerflite
Posted 2020-09-09 2:29 PM (#603058 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes, it fits. It's a tighter fit, but it works. The original push rod to the newer master has a rubber keeper on it. It won't work with that keeper, so I leave it out.

Edited by Powerflite 2020-09-09 2:47 PM
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LD3 Greg
Posted 2020-09-10 12:07 AM (#603068 - in reply to #601678)
Subject: Re: Single circuit to dual circuit


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51coronet - 2020-08-04 8:59 AM

Best flaring tool I have used so far is ridgid
https://www.amazon.com/RIDGID-83037-Precision-Ratcheting-Flaring/dp/...

It is nearly automatic, makes perfect flares each time, can do stainless line easily, not very expensive considering how well it works. You cant lose either piece with how its permanently attached to each other which is weird for me since I have used the dual piece ones for 20+ years. It just works well. Very nice tool. It moves in an orbital motion which flares line very nice. Old ones just pressed into the hole and relied on the tool to hold it without the tube slipping downward. Moving in a small orbit is the proper way to flare lines.


But, does it do double flares? I don’t see the double flare anvils in the pic.

Greg
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1960fury
Posted 2020-09-10 7:35 AM (#603071 - in reply to #603068)
Subject: Re: Single circuit to dual circuit



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LD3 Greg - 2020-09-10 12:07 AM

51coronet - 2020-08-04 8:59 AM

Best flaring tool I have used so far is ridgid
https://www.amazon.com/RIDGID-83037-Precision-Ratcheting-Flaring/dp/...

It is nearly automatic, makes perfect flares each time, can do stainless line easily, not very expensive considering how well it works. You cant lose either piece with how its permanently attached to each other which is weird for me since I have used the dual piece ones for 20+ years. It just works well. Very nice tool. It moves in an orbital motion which flares line very nice. Old ones just pressed into the hole and relied on the tool to hold it without the tube slipping downward. Moving in a small orbit is the proper way to flare lines.


But, does it do double flares? I don’t see the double flare anvils in the pic.

Greg


Search for Ridgid 459 on Ebay.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l131...

It is not really a wear part, so used should be ok. Got mine for under 10 Dollars, like new, back when you could ship parts from the US to Europe. Excellent tool for the money. It does SAE 45° double flares, but you need the little adapters but they are cheap and easy to find.

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hemidenis
Posted 2020-09-10 7:25 PM (#603087 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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a thread like this one is the real reason for the creation of this website....helping other fellow members... Great job to everyone.
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Todd
Posted 2020-09-12 4:20 AM (#603119 - in reply to #603087)
Subject: Re: Single circuit to dual circuit



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I totally agree. Thanks to everyone here!!
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Todd
Posted 2020-11-18 2:01 PM (#605743 - in reply to #603119)
Subject: Re: Single circuit to dual circuit



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Hi Guys. I have to go back to this with a question.
I installed the master cylinder and all the special connections recommended to me in this thread fit very well. For the normal lines (from brake cylinders/hoses to the tee) I have
bought only 3/8-24 fittings in the short version - pls. see link (TN01 -left on the picture)

https://www.ebay.de/itm/Standard-SAE-Inverted-Flare-Brake-Line-Fitti...

The old lines sometimes had the same short 3/8-24 fittings on one side but longer 3/8-24 fittings on the other side. The longer ones mostly went into the wheel brake cylinders.

Can I use only the short fittings for all ends of the lines instead? Any concerns?
I've already tried this and they fit very well when i tighten it. I think they're not too short....why did they use the longer fittings?!

Edited by Todd 2020-11-18 2:07 PM
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Powerflite
Posted 2020-11-18 2:23 PM (#605744 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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The longer fittings aren't required as the thread length on the female side is the same. I'm not sure what the purpose for using the longer length was, except maybe it makes it easier to install & make sure it is straight. But anyway, you don't have to use long fittings. You can re-use the original fittings if they are in good shape, if you like.
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Todd
Posted 2020-11-18 3:40 PM (#605748 - in reply to #605744)
Subject: Re: Single circuit to dual circuit



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I got it. So i will go on working at the linings. Thanks a lot again for your support.
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1960fury
Posted 2020-11-18 4:12 PM (#605750 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes, the longer thread isn't required and all of the original cars I ever owned never had the long thread at the wheel cylinders but I think on the distribution block, on the line coming from the MC with a reinforcement sleeve on the brake line (1/4"). I theory it makes sense since it prevents, or reduces movement of the brake line at the secton of the brake line that is most likely to crack, the transition from flare to straight, covered by the fitting. Keep in mind, there is always some movement between the frame and the body.
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samstrader
Posted 2020-11-19 2:34 AM (#605769 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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On my 1955 Plymouth, a brake hose was used to connect the master cylinder to the distribution manifold. Do people usually keep using a hose or do they replace the hose with steel brake line? The distance between the master cylinder and the distribution manifold is far enough apart that there is plenty of room for flex of a brake line I think. I'm asking this because of Sid's comment regarding movement between the frame and the body.
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Powerflite
Posted 2020-11-19 2:44 AM (#605771 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Steel line with a loop. The loop will provide some flex movement to prevent the line from cracking.
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samstrader
Posted 2020-11-19 2:53 AM (#605773 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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Thanks Nathan, I like a steel line better than a hose and there is plenty of room for loop or several turns in the line that will provide flex.
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1960fury
Posted 2020-11-19 7:30 AM (#605777 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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On 60/61s the distribution block is mounted on a flexible bracket and the main line from the MC is reinforced at the ends, or at least the lower end, so there is no loop required.
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Todd
Posted 2020-11-19 12:03 PM (#605789 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Okay, the hint with movement between frame and body is very good. Please look at the pictures. This is my first job with self-made brake lines. So please don't be so strict. Can I leave it like that, or do I have to have a loop in front of the master brake cylinder?

[img]https://thumbs.picr.de/39900288fm.jpg[/img]

[img]https://thumbs.picr.de/39900287dz.jpg[/img]

[img]https://thumbs.picr.de/39900286ph.jpg[/img]

[img]https://thumbs.picr.de/39900285my.jpg[/img]




Edited by Todd 2020-11-19 12:06 PM
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samstrader
Posted 2020-11-22 8:18 PM (#605941 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I think this is an absolutely beautiful job and I also think you have plenty of flex. The lines have more than one turn which gives flex and they are long horizontal legs that also help with flex. Additionally, the distribution manifold is mounted on a bracket that also gives a little flex.

It looks like the brake line from the front port on the master cylinder might be touching the emergency brake cable. If it is, it would be better if the brake line didn't touch anything so that there is no chance of rubbing a hole in the brake line with vibrations.

You did a beautiful job and now your car is much safer since you have a much improved brake system.
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Todd
Posted 2020-11-23 4:12 AM (#605948 - in reply to #605941)
Subject: Re: Single circuit to dual circuit



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Wow thanks a lot for the compliment
I will check the line and the emergency cable.
I have to say that I enjoy flaring more than bending lines

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Todd
Posted 2020-11-28 2:00 PM (#606130 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Folks, I can't get the brakes bleed. The new dual-circuit master has experienced extensive benchbleeding. Installed and on all nipples, BF arrives. Bubble free! Have already depleted 1.5 liters. But ZERO pressure on the pedal. I'm still going crazy here. The brake circuits are separated ... even on the two rear wheels, after a bubble-free venting, there was zero pedal pressure. Then also done at the front and zero pedal pressure. That's impossible.
Benchbleeding was successful, no bubbles.

I have now ordered a new one (60's mopar Bendix style maste cylinder). Can you think of anything else .... did I miss something ....? The new pipes are tight, nothing is dripping anywhere

Edited by Todd 2020-11-28 2:01 PM
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wizard
Posted 2020-11-28 3:54 PM (#606132 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Manual brakes or power brakes?
Wrong pedal ratio?
Brake shoes adjusted correctly?
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1960fury
Posted 2020-11-28 5:09 PM (#606134 - in reply to #606132)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-11-28 3:54 PM

Manual brakes or power brakes?
Wrong pedal ratio?
Brake shoes adjusted correctly?


Manual brakes.

Always try to pin the problem down. Have you plugged the MC at the ports for testing? Continue that way until you find the problem.
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56D500boy
Posted 2020-11-28 9:49 PM (#606141 - in reply to #606130)
Subject: Re: Single circuit to dual circuit



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Todd: You might want to review "Dels56"'s thread on "Spongy Brakes". He had similar problems with his new dual circuit MC:

http://www.forwardlook.net/forums/forums/thread-view.asp?tid=74238&...



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Todd
Posted 2020-11-29 4:01 AM (#606147 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Thanks for reply folks. Manual brakes, pedal ratio perfect, shoes lightly grinding, all ok. Plugged the ports only on the bench. Worked, has had pressure when stroking.
My old single master has 1.125" bore, the bendix has 1" bore. Can this be the reason?
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wizard
Posted 2020-11-29 4:50 AM (#606148 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes of Course, the displacement must be the same Todd, Most probably You should have pressure if You pump the brakes fast. The supplied volume of brake fluid must be the same as the oem mc.
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Todd
Posted 2020-11-29 6:10 AM (#606150 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Okay the new master must have the same bore size. In this case i need a drum/drum master with 1.125 " bore. Hard to find, i did not found one yet....Does anyone have any advice?
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wizard
Posted 2020-11-29 6:52 AM (#606151 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes Todd, but mind that the stroke must deliver the same volume as well. Divide by six, the front cylinders must have 4 of this volume and the rear cylinders must have 2.

So, practically, mount the oem cylinder in a wise, fill up and pump a couple of strokes. Measure a full stroke volume.
Do the same with the new cylinder and check the volume for each port. If the new cylinder supplies the same volume for both ports, then it will never work without a adjustable brake reduction valve for the rear circuit.

Even with this valve, you will have a low pedal with the lesser diameter of the m/c

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Todd
Posted 2020-11-29 9:44 AM (#606154 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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That sounds logical and understandable. But how am I supposed to do it. I can't buy some masters and then measure whether it fits. There are also no volume specifications for new masters. If you are lucky, the size of the bore is indicated, nothing more. Here on the board, many people have surely already converted from this single master, which is probably the same for almost everyone, to a dual master. It should still be possible to find out which dual master is suitable for the conversion, in the case of drums around....
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wizard
Posted 2020-11-29 10:20 AM (#606155 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I've been on the forum for some years now, but I still havn't seen one thread about sucessfully installed dual circuit m/c, drum/drum or disc/drum or for that matter disc/disc. In fact, I remember mostly problems about this.

That said, I don't think the braking power of only the rear drums would be much better than the emergency brake if the front circuit should fail. If the rear circuit would fail, the braking force will be far better than the emergency brakes though.

Hypothetically, if a dual circuit m/c gives the same volume in both ports, it would be possibly to hook up a diagonal system, left front and right rear, right front and left rear. Perhaps the pulling forces would be too steep anyway.

A thing came to my mind Todd, does the new m/c has a residual valve for both circuits?
If not, that might be the core of the problem, since residual valves are used to maintain constant pressure on the brake system.

For drum brakes, a 10 lb. residual valve is used to hold pressure against the springs in the drum. This allows the drum brake to engage more quickly and reduces pedal travel.

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wizard
Posted 2020-11-29 10:28 AM (#606156 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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See also this old one from the cellars http://www.forwardlook.net/forums/forums/thread-view.asp?tid=52082&...


And these ones https://www.summitracing.com/int/search/part-type/residual-pressure-...
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Powerflite
Posted 2020-11-29 11:42 AM (#606159 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Sven, the only reason you don't see successful installs is because we don't post about them. Also people with problems don't usually post when they solve the problem. But I assure you that there are many hundreds of successful dual circuit master installs. I have done at least seven of them and haven't had any issues. If he truly has zero brakes, then there is a faulty part that is either leaking, has trapped air in it, or not holding pressure. A small bore master will travel much longer than you would generally like, but it would at least create pressure at the end of its stroke. So he needs to start investigating where the problem lies. The only time I encountered an issue similar to this, I eventually found that I had a bad rear hose that was seeping. I found this because when I plugged the rear line, everything worked as it should. He needs to plug the master off one by one and see where the problem lies as Sid suggested.

Edit: I have also encountered a time when I purchased a new master that was bad right out of the box.

Edited by Powerflite 2020-11-29 11:46 AM
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56D500boy
Posted 2020-11-29 12:37 PM (#606161 - in reply to #606159)
Subject: Re: Single circuit to dual circuit



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Powerflite - 2020-11-29 8:42 AM
Edit: I have also encountered a time when I purchased a new master that was bad right out of the box.


This is exactly why I posted the link to Dels56 "Spongy Brakes" thread. That is what Del found out: Bad master right out of the box.

(And here's me with a new Chinese Raybestos dual master that I have had for a couple of years and not installed yet. Oh boy.)



Edited by 56D500boy 2020-11-29 12:38 PM
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wizard
Posted 2020-11-29 12:40 PM (#606162 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Thanks' Nathan, then I kindly ask our members that have sucessfully installed a dual circuit master cylinder with drum/drum system to post the m/c they installed and the diameter of the bore.

It must be frustrating for the ones wanting to do this modification to "invent the wheel" all the time.

We could then try to collect this info in one thread for future use.

Yes, I'm aware that new m/c's sometimes comes with damaged parts and/or wrongly mounted parts as well.
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Todd
Posted 2020-11-29 12:44 PM (#606163 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Thanks all. The dual has built in residual valves. I pulled the primary piston but everything looks fine. I'll reassemble it and then do the pressure test when it's installed. Plug one port at a time and depress the pedal ....
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Todd
Posted 2020-11-29 12:47 PM (#606164 - in reply to #606162)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-11-29 12:40 PM

Thanks' Nathan, then I kindly ask our members that have sucessfully installed a dual circuit master cylinder with drum/drum system to post the m/c they installed and the diameter of the bore.

It must be frustrating for the ones wanting to do this modification to "invent the wheel" all the time.

We could then try to collect this info in one thread for future use.

Yes, I'm aware that new m/c's sometimes comes with damaged parts and/or wrongly mounted parts as well.


Yes that is a great idea !!
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1960fury
Posted 2020-11-29 1:40 PM (#606165 - in reply to #606155)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-11-29 10:20 AM

I've been on the forum for some years now, but I still havn't seen one thread about sucessfully installed dual circuit m/c, drum/drum or disc/drum or for that matter disc/disc. In fact, I remember mostly problems about this.




Than you forgot about mine. I changed from stock to Wilwood disc/disc with dual Wilwood MC in 98 or 99 and it went without any problems.
Didn't even bench bleed (because I didn't know about that).
I installed a residual valve years later becaue after prolonged driving w/o braking the first brake application the pedal travel increased and delayed braking.

Most people run into problems because they forget DRUMS always need a residual valve and most aftermarker dual MC's don't have them built in,
like the OE MC.
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wizard
Posted 2020-11-29 2:40 PM (#606167 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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No Sid, I didn't forget that you made a sucessfull installation - you chose state of art parts that were ment to be working together. A professional set-up for sure.

Many here perhaps does not want to go "all-in" in a project, so they're looking for a more economic solution.

As you wrote, drums really must have residual valves with the proper pressure value (10 lbs), not just "any" residual valves.

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Powerflite
Posted 2020-11-29 2:47 PM (#606168 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I would agree, except that the 1 1/8" OEM master doesn't actually have a residual valve in it, at least for '56-'58. I know this because I am running disc brakes with the original master and there is no drag on them at all like there would be if there was a residual valve in place. I suspect that things changed once the drum brake design changed, but not sure when a residual valve started to be used in them.

Edited by Powerflite 2020-11-29 2:48 PM
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1960fury
Posted 2020-11-29 3:51 PM (#606171 - in reply to #606168)
Subject: Re: Single circuit to dual circuit



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Powerflite - 2020-11-29 2:47 PM

I would agree, except that the 1 1/8" OEM master doesn't actually have a residual valve in it, at least for '56-'58.


That would really surprise me. Not rarely the old residual valves are not working properly and therefore could work with discs, that require @ 2lbs pre-pressure, IIRC.
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1960fury
Posted 2020-11-29 3:57 PM (#606172 - in reply to #606168)
Subject: Re: Single circuit to dual circuit



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Powerflite - 2020-11-29 2:47 PM

I would agree, except that the 1 1/8" OEM master doesn't actually have a residual valve in it, at least for '56-'58.


This 39-58 Mopar kit shows a valve:

https://www.ebay.com/itm/Dodge-Plymouth-Truck-cars-1939-1958-New-Mas...
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Powerflite
Posted 2020-11-29 4:00 PM (#606173 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yeah, maybe the valve was bad on them, but I've tested it on 4 vehicles, and they were all the same.
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1960fury
Posted 2020-12-01 9:29 AM (#606210 - in reply to #606171)
Subject: Re: Single circuit to dual circuit



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1960fury - 2020-11-29 3:51 PM

Powerflite - 2020-11-29 2:47 PM

I would agree, except that the 1 1/8" OEM master doesn't actually have a residual valve in it, at least for '56-'58.


That would really surprise me. Not rarely the old residual valves are not working properly and therefore could work with discs, that require @ 2lbs pre-pressure, IIRC.


Did some research and of course pre-59 master cylinders had residual valves too. All drum systems need some pre-pressure in the lines.

Edited by 1960fury 2020-12-01 10:30 AM
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Todd
Posted 2020-12-01 11:27 AM (#606212 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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In the meantime, I've tested a lot. The new master has pressure on every outlet. So it's not defective.
After bleeding, however, as before, there is no brake pressure on the pedal. When the pedal is fully depressed to the floor, the rear brakes are gently braked.
But the pedal travel is far too long.
Then I installed and bleeded the old single circuit master. I have normal, full brake pressure on the pedal.
So it can only be due to the smaller 1 "brake piston of the new master. The piston is too small. But there is no drum / drum dual master with a 1,125" bore. There are many dual masters for disc / drum.
What do I do now? I stick with the one-circuit system. The lines and fittings are all new and therefore safe. At some point I'll maybe convert the front to disc. But not just yet.
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wizard
Posted 2020-12-01 11:55 AM (#606213 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Todd, is the new dual circuit m/c for disc/drum or disc/disc?

The disc normally have a residual valve of roundabout 2 lb, while drums should be 10 lb.

I'm not sure that new residual valves is the solution, but if the ones you have in the m/c now ar 2 lb in both ports, then this is part of the problem.
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56D500boy
Posted 2020-12-01 11:56 AM (#606214 - in reply to #606212)
Subject: Re: Single circuit to dual circuit



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This sounds like a situation I had when I first started driving, in a 55 Dodge, back in 1967. The brakes were "fine" (as long as you pumped them a couple of times). *HOWEVER* if, after pumping the brakes up, you kept your foot on the pedal, the pedal very slowly sank to the floor. I had no clue. I was 16 and had not done much work on a car.

But my dad who was very mechanically inclined knew what the issue was so I bought a MC repair kit and after we removed the MC, he instructed me on the replacement of the "cup"/seal at the front of the piston. It had a nick in it (or it was just worn -I don't recall). I lightly sanded the piston bore with fine (800 grit) sand paper, replaced the cup (and the other bits that came in the kit) and everything was good.

So it sounds (to me) like your problem is that there is a piston cup/seal (or piston bore) issue.











Edited by 56D500boy 2020-12-01 2:22 PM
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Todd
Posted 2020-12-01 12:20 PM (#606216 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Sven: It's a drum / drum dual master;
https://www.ebay.de/itm/1960s-Mopar-Drum-Brake-2660809-BENDIX-Master...

56D500boy: as i wrote, the new master seemed to be ok, cause he has pressure when you plug the ports and try to stroke the piston, so much pressure that you are not able to stroke the piston.

Edited by Todd 2020-12-01 12:22 PM
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wizard
Posted 2020-12-01 12:33 PM (#606218 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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So Todd , you 've confirmed that the circuit in the car is ok by reinstalling the old m/c and you've confirmed that the new m/c is ok by plugging the ports.

That leaves only the diameter and stroke differences.
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Todd
Posted 2020-12-01 12:48 PM (#606220 - in reply to #606218)
Subject: Re: Single circuit to dual circuit



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YES - I came to the same conclusion. It can only be due to the piston that is too small.
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Powerflite
Posted 2020-12-01 12:51 PM (#606221 - in reply to #606220)
Subject: Re: Single circuit to dual circuit



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...or a problem with the connections from the master to the rest of the system.
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Todd
Posted 2020-12-01 12:53 PM (#606222 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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How do you mean that exactly?
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Powerflite
Posted 2020-12-01 1:51 PM (#606223 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I have used smaller masters before and they do allow a lot more travel, but they have always developed pressure in the system. I know that Neil and other people have used that master successfully as well. So I tend to think there is something else that is the real problem. You have 4 connections & one plug that are different when you swap to the single circuit master. I have personally found that the plugs that are sold don't seal well so that would be my first guess as to where the problem lies. Those plugs also can damage the distribution block if you tighten them a lot because they aren't made to seal the same as the line. To plug the port, I always take a line (with a connector on it), cut it short, weld the end of the line shut, and then braze a coating of brass over the top of it to ensure it is sealed. You also have a union at the rear brake line. Sometimes those can come loose if you don't tighten them properly so it could be worth checking.

But I agree with your sentiment to retain the single master with the drums. I don't think the small safety factor with the dual is worth the effort for an original system. Neil ultimately felt the same way about it.



(39900287dz.jpg)



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Todd
Posted 2020-12-02 4:01 AM (#606254 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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New thought: A disc / drum master with the large bore should work if a 10 lb residual valve is installed for the disc port brake line at the front. Any concerns?

Disc/drum masters with 1.125" bore are easy to get.




Edited by Todd 2020-12-02 4:02 AM
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Todd
Posted 2020-12-02 4:13 AM (#606255 - in reply to #606254)
Subject: Re: Single circuit to dual circuit



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This one has 1.125" bore, residual 10lb for rear port almost built in, and able to mount directly to firewall w/o any adapter:

https://www.ebay.com/itm/1966-1970-Mopar-Bendix-Style-Manual-Disc-Dr...
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wizard
Posted 2020-12-02 4:29 AM (#606256 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Hypothetically yes Todd. The disc/drum mc displacement must be close to the oem mc
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samstrader
Posted 2020-12-02 6:24 AM (#606260 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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Are you bleeding the brakes by yourself or are you having someone pump the brakes while you bleed off at the wheels while they are pushing down. I have always been able to get a better bleed when I have my wife push down the brake pedal. The step is to push down the brake pedal until you get some pressure. Once you have pressure, bleed out the wheel cylinder until the brake pedal goes almost all the way down, but not all the way down, and then close the bleeder at the wheel before the pedal hits bottom. This way you always have a positive pressure in the brake system when you open a wheel cylinder bleeder. You are trying to never have less than positive pressure when any bleeder is open. You have to do this a bunch of times at each wheel but if you do it right, you never suck air back in at the wheel cylinder. Every time I try to bleed to a bottle, I don't get as good a bleed.

It just sounds to me like you still have a lot of air in the system. It is hard to troubleshoot without being there but sounds to me like just still a lot of air in the system. It doesn't take much air to make the brakes not work at all.
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Todd
Posted 2020-12-02 6:46 AM (#606262 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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No i have no air in the system because the old master works perfect as always as i wrote - very good pedal pressure. I always use a one-way bleeder valve when bleeding. No chance to suck air back in the system when bleeding.

Edited by Todd 2020-12-02 6:49 AM
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Powerflite
Posted 2020-12-02 12:03 PM (#606270 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I just made a plug for my '56 Fury yesterday. This is what it looks like. The '55-'56 uses a non-standard thread size (7/16-20 instead of 7/16-24) at the top port so I am waiting to receive tube nuts for it before I can finish it.



(56Fury White Brake Plug.jpg)



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Todd
Posted 2020-12-02 12:25 PM (#606276 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Wow looks pretty nice!!
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1960fury
Posted 2020-12-02 4:08 PM (#606285 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Something doesn't make sense here. You mean even if you pump, the pedal stays soft or sinks to the floor? That means the reservoir is empy then and the MC sucks air?
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56D500boy
Posted 2020-12-02 5:02 PM (#606289 - in reply to #606270)
Subject: Re: Single circuit to dual circuit



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Powerflite - 2020-12-02 9:03 AM
I just made a plug for my '56 Fury yesterday. This is what it looks like. The '55-'56 uses a non-standard thread size (7/16-20 instead of 7/16-24) at the top port so I am waiting to receive tube nuts for it before I can finish it.


Nathan: I like what you've done but I can't weld (no equipment/skills, etc) so I would need a non-welding option. Wouldn't something like this Edelmann Union Tee work for the distribution of pressurized brake fluid to the front brakes?





(EdelmannUnionTeeDetails.jpg)



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samstrader
Posted 2020-12-02 5:13 PM (#606290 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I understand what you are saying. The wheel cylinders need more fluid than is available from the master cylinder to make the shoes contact the drums. By the time your brake pedal hits the floor, you still have not pumped enough fluid from the master cylinder to move the brake shoes to the drums. So, you need more fluid displacement from your new master cylinder. Fluid displacement is diameter of the cylinder times distance of the stroke. Your original master cylinder must displace more fluid than the new one so why would this be? If you look at the schematic above that Dave posted that shows how dual master cylinders work, you see the fluid intake and return ports. Fluid displacement to the wheel cylinders doesn't start until the cup is past this port and pushing toward the wheel cylinders. Is it possible that the preload from your brake pedal on your new master cylinder is different than the original. If on your new master cylinder, the plunger is a long way back from this fluid intake and return port, you will use up a lot of your pedal travel before you start moving fluid to the wheel cylinders. Your original wheel cylinder is probably set up so this port covers much earlier than on your new one. Is there a way to adjust the length of the stroke on the new master cylinder.

If you adjust your brake drums tight so that you have drag, that might solve the problem because it will take less fluid to make the shoes hit the drums. But it creates the new problem of drag on the wheels, heating up the drums, and wearing out your brake shoes early. It seems to me like a residual valve would make the shoes stay close to the drum just the same way as adjusting the shoes close to the drums. I'm not sure I see much difference in the benefit of the residual valve versus just adjusting your brakes tighter. The real issue is that your new master cylinder is not displacing enough fluid to move the wheel cylinders far enough so that the shoes contact the drums.

If your new master cylinder pumps up tight when it is operated when it is plugged off, and the OEM wheel cylinder will pump enough fluid to make the shoes touch the drum, then the only thing that can be wrong is that the new wheel cylinder is not displacing as much fluid as the original wheel cylinder. Why is this? That's all you need to figure out. You can't have any leaks or the OEM would not work, and you would see the leaks. This is just a fluid displacement issue.

Anyway, just my two cents worth.
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1960fury
Posted 2020-12-02 5:23 PM (#606292 - in reply to #606289)
Subject: Re: Single circuit to dual circuit



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56D500boy - 2020-12-02 5:02 PM

Nathan: I like what you've done but I can't weld (no equipment/skills, etc) so I would need a non-welding option. Wouldn't something like this Edelmann Union Tee work for the distribution of pressurized brake fluid to the front brakes?



You actually only need a bolt, 7/16-20 or -24.

To not just rely just on teflon tape (which ich actually 100% safe) you could "machine" the end of the bolt that faces the inside (which is easily done with a simple drill and angle grinder) so it seals at the sharp edge of the inside cone too.
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Powerflite
Posted 2020-12-02 7:34 PM (#606294 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Interesting idea about machining your own 45 degree cone to seal as a plug, Sid. The one at the bottom is 3/8-24.

Dave, the tee you show will work, just won't be mounted like the factory one and routing will be different.
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1960fury
Posted 2020-12-02 8:22 PM (#606295 - in reply to #606294)
Subject: Re: Single circuit to dual circuit



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Powerflite - 2020-12-02 7:34 PM

Interesting idea about machining your own 45 degree cone to seal as a plug, Sid.


It is surprisingly accurate if the bolt is spinning fast in a drill and you shape it with an angle grinder. I even modified an AN fitting adapter from 37° to 45° on one side, when I made my own PS pressure line with steel to braided teflon line. Works great.
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wizard
Posted 2020-12-03 3:05 AM (#606299 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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So, since this got me curious I went out and checked some spare parts and came to some conclusions;

The oem master cylinder has a diameter of 1-1/8" (28,575mm) and a maximum stroke of approximately 1.150" (29mm), supplying a displacement of 18,6 cm³
The oem wheel cylinder has a diameter of 1-1/8" (28,575mm)
Ratio 1:1

This means that if the m/c piston is pressed in "full stroke", the 6 wheel cylinder pistons will move 4,8mm each outwards.

So, lets assume that the stroke is the same in the "new" dual circuit cylinder;

Master cylinder diameter 1" (25,4mm), maximum stroke approximately 1.150 (29mm) supplying a displacement of 14,7 cm³
The oem wheel cylinder has a diameter of 1-1/8" (28,575mm)
Ratio 1:075

Hypothetically, this means that if the m/c piston is pressed in "full stroke" 6 wheel cylinder pistons will move 25% less, approximately 3,7mm each outwards.

So, with the same stroke/displacement it might work, but always with a very low pedal.

Perhaps someone better than me in mathematics could correct my theory here?

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Todd
Posted 2020-12-03 3:32 AM (#606300 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Thank you for your effort Sven. That reveals the biggest problem: one stroke of the dual master is not enough to move the wheel brake cylinders. In my case, a very slight braking effect only occurs when the pedal is completely on the floor. And I mean completly on the floor. This master ist not suitable.

My options: try a 1,125 dual master for disc/drum, or enjoy the OE master with new brake lines.
I think I'll take the second solution.
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wizard
Posted 2020-12-03 4:08 AM (#606301 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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You're welcome Todd.

If you go for the oem m/c, please do the following;

- Remove all wheel cylinders, wash them good and inspect the bores and rubber parts. Any flaw means new stuff.
- Clean and inspect the m/c, even more important, there must be no rust pits in the bore.
- Flush the brake lines with alcohol.
- Inspect the brake hoses and change them at any flaw detected.
- Inspect all the brake lines for any wear or rust. If you need to change, use ONLY steel or copper/nickel lines, stay away from copper as it's not safe for vibrations and very easily micro cracks can occure during the coning.
Do the above with scrutiny and do not accept any flaw.

Now you have to chose the brake fluid, I can recommend DOT5, synthetic even at a much higher cost since there will be no rusty parts.
You can paint your m/c without risk of having a grim result after spillage.

If you do all the above, you will have an as safe as possibe single circuit brake system, this is what I did.

Since you have manual brakes, it should be fairly simple to add a small float with a switch for low level warning on the m/c. You should be able to get some ideas as for parts to use from a scrap yard.

The other option far as I understand is to go "all in" like Sid did, open up your wallet and get a Wilwood dual circuit brake system.

Mind that many kits on the market uses Mustang parts, suitable for the low vehicle weight, but not for heavier cars.



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1960fury
Posted 2020-12-03 11:35 AM (#606307 - in reply to #606299)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-12-03 3:05 AM

So, since this got me curious I went out and checked some spare parts and came to some conclusions;

The oem master cylinder has a diameter of 1-1/8" (28,575mm) and a maximum stroke of approximately 1.150" (29mm), supplying a displacement of 18,6 cm³
The oem wheel cylinder has a diameter of 1-1/8" (28,575mm)
Ratio 1:1

This means that if the m/c piston is pressed in "full stroke", the 6 wheel cylinder pistons will move 4,8mm each outwards.

So, lets assume that the stroke is the same in the "new" dual circuit cylinder;

Master cylinder diameter 1" (25,4mm), maximum stroke approximately 1.150 (29mm) supplying a displacement of 14,7 cm³
The oem wheel cylinder has a diameter of 1-1/8" (28,575mm)
Ratio 1:075

Hypothetically, this means that if the m/c piston is pressed in "full stroke" 6 wheel cylinder pistons will move 25% less, approximately 3,7mm each outwards.

So, with the same stroke/displacement it might work, but always with a very low pedal.

Perhaps someone better than me in mathematics could correct my theory here?



Just simpler. If you take the same stroke, and the wheel cylinders remain the same, it is just 1.1/8" bore VS 1" bore that you need to know that the movement will be less.... then again, the dual MC has 2 pistons....?
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wizard
Posted 2020-12-03 11:49 AM (#606310 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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The two pistons are agood part ofthe problem Sid. I imagine that the "new" m/c is n for 4 cylinders, 2 front and 2 rear and with lesser diameter, let's say 1". That would be just fine as the displacement of the stroke will give the same portion to front and rear. Now, if the "new" m/ c is mounted in a Car with 6 cylinders, it's a problem, since One port must supply 4 cylinders and the other port only 2. Most probably it's the rear cylinders Todd is giving some resistance/brake from on the End of the pedal travel as the front once would not move sufficiantly with the same portion of fluid.
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1960fury
Posted 2020-12-03 5:38 PM (#606326 - in reply to #606310)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-12-03 11:49 AM

The two pistons are agood part ofthe problem Sid. I imagine that the "new" m/c is n for 4 cylinders, 2 front and 2 rear and with lesser diameter, let's say 1". That would be just fine as the displacement of the stroke will give the same portion to front and rear. Now, if the "new" m/ c is mounted in a Car with 6 cylinders, it's a problem, since One port must supply 4 cylinders and the other port only 2.


Is the number of wheel cylinders of importance and not the number/diameter of the pistons/bore? It is the pistons that needs to move regardless where it is installed. There are 4 pistons in the rear and 4 in front.
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samstrader
Posted 2020-12-03 10:18 PM (#606335 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I have learned a lot about brake systems because of this thread. And I apologize for adding confusion. I didn't know anything about residual valves so I studied them and have included two links I thought were interesting. I can now see several advantages of using these valves and they are inexpensive and easy to install. I think newer style master cylinders might have these residual valves already installed in the outlet nozzles on the master cylinder.

Sevn's calculation of the volume of a stroke on the master cylinder is interesting because it shows that a lot of volume is lost when you reduce the diameter of the bore from 1.125 inches to 1.000 inches. 1/8 of an inch doesn't seem like much but it reduces the volume more than you would think.

I searched Rock Auto for a while and couldn't find any Dodge dual cylinder master cylinders with 1 1/8 inch bores. Cardone does offer a rebuild service that says their rebuilt cylinders have 1 1/8 inch bores. If this is really correct, I wonder if they just bore out old wheel cylinders to 1 1/8 inch and refit with 1 1/8 internals. I'm pretty sure this would be possible because I've sent in cores in the past that had pits so deep that you would have to bore out an extra 1/8 inch to clean them up. I had all of my wheel cylinders and master cylinder sleeved with stainless steel a few years ago and I'm sure they had to bore out to install the sleeves. So maybe this is an option.

Anyway, sorry for any confusion I may have added.

http://www.how-to-build-hotrods.com/brake-system.html

https://www.bing.com/images/search?q=brake+line+residual+...
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wizard
Posted 2020-12-03 11:59 PM (#606342 - in reply to #606326)
Subject: Re: Single circuit to dual circuit



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1960fury - 2020-12-03 11:38 PM

wizard - 2020-12-03 11:49 AM

The two pistons are agood part ofthe problem Sid. I imagine that the "new" m/c is n for 4 cylinders, 2 front and 2 rear and with lesser diameter, let's say 1". That would be just fine as the displacement of the stroke will give the same portion to front and rear. Now, if the "new" m/ c is mounted in a Car with 6 cylinders, it's a problem, since One port must supply 4 cylinders and the other port only 2.


Is the number of wheel cylinders of importance and not the number/diameter of the pistons/bore? It is the pistons that needs to move regardless where it is installed. There are 4 pistons in the rear and 4 in front.


Yes of Course Sid, both number of Wheel cylinders as well as the diameter is important as the displacement of the m/c is divided by the number of Wheel cylinders and the diameter gives the ratio/movement
I's a Dodge 60 with oem brakes, so 4 front cylinders and 2 rear cylinders
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1960fury
Posted 2020-12-04 9:26 AM (#606350 - in reply to #606342)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-12-03 11:59 PM

1960fury - 2020-12-03 11:38 PM

wizard - 2020-12-03 11:49 AM

The two pistons are agood part ofthe problem Sid. I imagine that the "new" m/c is n for 4 cylinders, 2 front and 2 rear and with lesser diameter, let's say 1". That would be just fine as the displacement of the stroke will give the same portion to front and rear. Now, if the "new" m/ c is mounted in a Car with 6 cylinders, it's a problem, since One port must supply 4 cylinders and the other port only 2.


Is the number of wheel cylinders of importance and not the number/diameter of the pistons/bore? It is the pistons that needs to move regardless where it is installed. There are 4 pistons in the rear and 4 in front.


Yes of Course Sid, both number of Wheel cylinders as well as the diameter is important as the displacement of the m/c is divided by the number of Wheel cylinders and the diameter gives the ratio/movement
I's a Dodge 60 with oem brakes, so 4 front cylinders and 2 rear cylinders


Well, again, the rears are duals (1x2 pistons each per side) the front singles (2x1 piston per side). That's 4 pistons front and 4 pistons at the rear. The number of wheel cylinders ist not of importance.
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wizard
Posted 2020-12-04 12:37 PM (#606358 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes Sid, but that means that the rear piston max stroke is divided by 2 which makes the rear brakes less powerful and also very important to adjust the rear brakes as close to the drum as possible.
The new mc is surely for wheel cylinders with 1" diameter and two pistons per cylinder. The new drum/drum system had 1 cylinder per wheel if I recall correctly.
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Todd
Posted 2020-12-04 1:18 PM (#606361 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Well folks i will now try this 1.125" piston disc/drum master https://www.ebay.com/itm/1966-1970-Mopar-Bendix-Style-Manual-Disc-Dr...

with a extern 10 lb residual valve for the front lines. I will let you know what happens.
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jboymechanic
Posted 2020-12-04 3:42 PM (#606363 - in reply to #606361)
Subject: Re: Single circuit to dual circuit



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Todd, I think you will find that your pedal will firm up with the larger bore MC. If your lines are truly bled of air and you can push your pedal to the floor that means you are not trying to compress the liquid, which is not compressible, in your system. You might be moving your wheel cylinder pistons but not to the point that they all bottom our and you begin to feel the increased pressure. A larger bore with the same pedal stroke will move more volume get you to that point.

I have added front disc brakes to 4 old mopars now, the first was a great learning experience and made my last three go flawlessly. Like you, I got my system together and the car stopped, but the pedal was soft and went to the floor. The MC had a 1 & 1/32" bore, so I switched to a 1 & 1/8" bore MC and the brakes were perfect.

By the way, later mopar MCs didn't have any residual valves build into them, instead they were external. You can then pick a MC bore of your liking and then add the external residual valves you need. Let us know how it goes.
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1960fury
Posted 2020-12-04 4:00 PM (#606365 - in reply to #606358)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-12-04 12:37 PM

Yes Sid, but that means that the rear piston max stroke is divided by 2 which makes the rear brakes less powerful and also very important to adjust the rear brakes as close to the drum as possible.
The new mc is surely for wheel cylinders with 1" diameter and two pistons per cylinder. The new drum/drum system had 1 cylinder per wheel if I recall correctly.


The rear brakes SHOULD be less powerfull, however, it does not matter where the pressure is divided, in a wheel cylinder or outside of it, like in the front. There is just one line going in, front or rear. Every piston has to move a certain amount for braking action, regardless if it is a single 2 piston wheel cylinder or 2 single pistons per wheel.
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wizard
Posted 2020-12-04 4:36 PM (#606368 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes of Course Sid, but everyone knows that the rear brakes must have less force than the front.
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1960fury
Posted 2020-12-04 4:52 PM (#606369 - in reply to #606368)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-12-04 4:36 PM

Yes of Course Sid, but everyone knows that the rear brakes must have less force than the front. :laugh:


It is the design of the 2 brake cylinders per wheel that makes the braking more effective, creating 2 "forward" brake shoes. The force should be the same from a single pot MC, if there is no restriction in the distribution block to the rear. The rears are NOT "less powerfull" because it is a dual cylinder. Again, where the force is divided is of no importance. 1 pessure line to 2 pistons, front and rear.
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jboymechanic
Posted 2020-12-04 5:10 PM (#606370 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Forgot to add this, helpful to pick out a master cylinder for your application:

http://therammaninc.com/files/categories/Moparts_Complete_Guide_to_...
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samstrader
Posted 2020-12-05 1:58 PM (#606415 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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Good job finding a 1 1/8 bore master cylinder Todd. I looked for an hour and couldn't find one. I bet this may fix you up.

Just one extra thought on brake line routings. It is better not to have a high spot in the line that can trap air. I think this doesn't matter too much since the line diameter is so small but just better. When we used to design piping systems in refineries, we always made sure of this.
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samstrader
Posted 2020-12-05 2:08 PM (#606416 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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One general type of question for the brake systems on these cars. During all of studying this, I found an article about nose diving when you put your brakes on hard and suddenly, which my car does. The article said that if this happens, it means the residual valve to the back wheels is not working (or in my case, the residual valve doesn't exist). Do all of these 1950s cars sort of nose dive when you put the brakes on hard? Have folks added a residual valve to the line going to the back drums to reduce this nose diving? Or is the nose diving just a normal part of these cars? Just wondering now that I have a new understand of the brake systems.

Thanks for your original question Todd because I have really learned a lot.

Sam
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1960fury
Posted 2020-12-05 5:06 PM (#606423 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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All cars nose dive. Of course our cars have softer springs and heavy engines but a faulty residual valve could make it worse (good point). You can make a night and day difference if you move the battery (that is in the worst possible location) to the right rear trunk.
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samstrader
Posted 2020-12-05 7:02 PM (#606428 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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That is a heavy battery and way up front. And it would also be nice to have it out of the way. I may look into moving it.

This has sure been a good learning discussion about brakes for me. Even applies to more modern cars.
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NC Adventurer
Posted 2020-12-06 6:21 PM (#606476 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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Here's a decent article on the issue of calculating master cylinder bore size and pedal ration: https://www.onallcylinders.com/2014/08/07/pedal-pushers-figure-pedal...

Will this M/C fit your needs? Bore is 1.125". https://www.autozone.com/brakes-and-traction-control/master-cylinder...
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Powerflite
Posted 2020-12-06 9:30 PM (#606482 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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On this thread, I show how to calculate all you could want to know about brake system design and I also implicitly show that a 1" master should build pressure in an all drum system without any issue as long as the brake shoes are adjusted to a reasonable level.

http://www.forwardlook.net/forums/forums/thread-view.asp?tid=71807
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Todd
Posted 2020-12-07 9:38 AM (#606490 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I'll find out this week when the new master has been delivered. Please be patient.

@ jboymechanic & NC Adventurer: Thank you for your interest in this topic and the helpful, interesting links.Many thanks to everyone who contributed to this topic.I will be back soon.....

Edited by Todd 2020-12-07 9:39 AM
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Todd
Posted 2020-12-12 1:07 PM (#606641 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Hi guys, I'll get back to you. The new disc / drum master with 1 1/8 "bore is built in. And .... YES .... it works! I have a firm pedal and really good brake pressure. BUT .... only when I push the pedal the second time The first step on the pedal is almost to the floor.
The rear port of the master has an internal 10 lb residual valve. For the front port I installed an external wilwood 10 lb (10 psi) residual valve into the line. On the picture you can see the position where I installed it (don't have a current picture yet - it is the picture with the old master with the small bore that did not work).

[img]https://thumbs.picr.de/40069177tl.jpg[/img]

What do you think, why is it that I only have firm pressure on the pedal the second time I push the pedal? Is the position of the external residual valve incorrect? Or are there still air bubbles in the brake lines after all? I bleed twice ...


Edited by Todd 2020-12-12 1:53 PM
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Powerflite
Posted 2020-12-12 2:50 PM (#606648 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Did you replace that plug yet?
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wizard
Posted 2020-12-12 3:27 PM (#606651 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Todd, do this test first;
Adjust the rear brake shoes to full contact, both sides and see if that gives something.
If not, adjust also the front brake shoes to full contact, both sides and see if you get some improvement.

If you get a firm pedal, press hard and make a measurement from the depressed brake pedal to the steering wheel or the dash. Release the pedal and wait 2 minutes - press down the pedal again and check if you have the same measurement as before - if not, then there's still some air trapped in the system.

If you don't get any improvement, then you must measure the displacement of the oem m/c and thereafter the combined displacement from the dual /mc and check if you have approximately the same amount of fluid.

Check also if you have more fluid from one of the ports in the dual m/c - if so, you must use that to the front wheels
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samstrader
Posted 2020-12-15 2:25 AM (#606736 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I agree with Sven about adjusting the brakes. If you have to pump to get good pedal, it means your brakes are too far away from the drum. I have been driving my car for about 300 miles with new brake shoes and now I have a low pedal on the initial press and it will stop the car but if I pump the brake one time, it get a high pedal. I know my brakes need adjusted and I will do that this weekend. What you are describing is exactly what we would get when I was a kid and we had to adjust the brakes. These old cars have zero automatic brake adjustment so you have to adjust them from time to time and you have to adjust them a second time pretty soon after you put new brake shoes because the brake shoes burn in and lose a little thickness.

It could be air in the lines but it sounds like brake adjustment to me. When you pump the brakes and get a high pedal, is it spongy or solid as a rock. Spongy is air and solid as a rock is shoe adjustment needed.

The great news is you are very close now. And I will know exactly how to put a dual cylinder on my car...
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Todd
Posted 2020-12-15 9:51 AM (#606741 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Hi friends. Sorry that I’m only getting back to you now. I have a lot to do on the job right now, and the working days are really long right now. When i pump and get a high pedal, it is solid as a rock. Can't push further downward. I have just readjusted the drums. If I adjust the brake shoes even more close to the drum, they rub too hard on them.
Sven: Unfortunately, I don't have the time for the tests at the moment and I'm a little too tired for that. I've already used over 4 liters of fluid and need a little break :)When I have time, I bleed the brake system again. There may still be some air in the system. I will keep you up to date.
Thanks again for all the helpful support, i really appreciate that.

Edited by Todd 2020-12-15 9:55 AM
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Todd
Posted 2020-12-15 12:08 PM (#606746 - in reply to #606741)
Subject: Re: Single circuit to dual circuit



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I have now read that it is common for dual-circuit brake systems to start bleeding at the front-wheel brake cylinder which is nearest to the master cylinder. That's new to me. Can you confirm that ???

Edited by Todd 2020-12-15 12:10 PM
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wizard
Posted 2020-12-15 1:00 PM (#606752 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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It's always the same procedure Todd, start with the wheel cylinder farest from the m/c - in a dual circuit that would be the front right lower wheel cylinder, front right upper wheel cylinder, front left wheel lower wheel cylinder, front left upper wheel cylinder, rear right wheel cylinder and rear left wheel cylinder. Naturally depending which port is using for front circuit.

If you adjust the brake shoes to full contact (blocked wheels) it will be easier to bleed out the eventual air.

Do my measuring test before you start to bleed. That will tell you if there's any air in the circuits.
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Todd
Posted 2020-12-15 1:20 PM (#606755 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Sven: unfortunaly it's too late for the test, I had to start over. During the last bleeding, the fluid in the master was used up and it drew in air. s**t happens. But i will do the measuring if i have to pump again at the second try. I will now set the brake shoes to full contact before bleeding.

I've been thinking about an important thing. It affects the external residual pressure valve for the front port: On the picture you can see where I have placed it. I suspect it is too far away from the master - because: when I install the brake line at the master port, there is of course air in the brake line between the master and the residual presssure valve at the beginning. If I now press the brake pedal and release it again, this air is sucked back into the master, because the way to the residual valve is too long. The residual valve must be installed directly on the master port. And you can certainly help me: I need an adapter with a male 9/16 - 20 "connection (into master) and a male 3/8 - 24" (into residual valve). Do you know where I can buy something like this? Is there such an adapter?

Or do i think wrong with my theorie?

Edited by Todd 2020-12-15 1:32 PM
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Powerflite
Posted 2020-12-15 1:45 PM (#606757 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Another common issue is the residual valves look like they come well seated and sealed. That often isn't the case. You need to remove the pipe threaded connectors and re-apply them with teflon tape to seal them well.
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Todd
Posted 2020-12-15 1:49 PM (#606758 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Good thought, I'll seal them beforehand.
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Todd
Posted 2020-12-15 2:31 PM (#606759 - in reply to #606752)
Subject: Re: Single circuit to dual circuit



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wizard - 2020-12-15 1:00 PM

If you adjust the brake shoes to full contact (blocked wheels) it will be easier to bleed out the eventual air.


You mean set the shoes to the fully released position Sven?
https://youtu.be/oVCb0TE0lMI

See at minute 4:00.....

Edited by Todd 2020-12-15 2:32 PM
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1960fury
Posted 2020-12-15 3:14 PM (#606763 - in reply to #606755)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-15 1:20 PM


I've been thinking about an important thing. It affects the external residual pressure valve for the front port: On the picture you can see where I have placed it. I suspect it is too far away from the master - because: when I install the brake line at the master port, there is of course air in the brake line between the master and the residual presssure valve at the beginning. If I now press the brake pedal and release it again, this air is sucked back into the master, because the way to the residual valve is too long. The residual valve must be installed directly on the master port. And you can certainly help me: I need an adapter with a male 9/16 - 20 "connection (into master) and a male 3/8 - 24" (into residual valve). Do you know where I can buy something like this? Is there such an adapter?

Or do i think wrong with my theorie?


It is not too far away, but of course the closer to the MC the better and of course you have to bleed the system again after the instalation of the residual valve so I don't get the problem.
All residual valves I have ever seen are tapped for 1/8 NPT threads.
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Todd
Posted 2020-12-15 3:35 PM (#606764 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Yes you're right. But Wilwood sell them with inverted 3/8 - 24 adapters to directly install the brake line.
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wizard
Posted 2020-12-15 4:01 PM (#606766 - in reply to #606759)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-15 8:31 PM

wizard - 2020-12-15 1:00 PM

If you adjust the brake shoes to full contact (blocked wheels) it will be easier to bleed out the eventual air.


You mean set the shoes to the fully released position Sven?
https://youtu.be/oVCb0TE0lMI

See at minute 4:00.....


The adjusting cam is an excenter Todd, so fully backed off will be locked wheels as well. Try and check
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1960fury
Posted 2020-12-15 4:02 PM (#606767 - in reply to #606764)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-15 3:35 PM

Yes you're right. But Wilwood sell them with inverted 3/8 - 24 adapters to directly install the brake line.


So wouldn't it be more logical and easier to search for, or fabricate a 9/16-20 to 1/8 NPT adapter? Also cleaner looking and a connection that can leak less.

Maybe you can just tap the 9/16 MC tube nut (if there's enough meat) and use a male/male 1/8 NPT to 1/8 NPT connector?
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Powerflite
Posted 2020-12-15 4:05 PM (#606768 - in reply to #606767)
Subject: Re: Single circuit to dual circuit



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I'm not following what you are saying Sid. All connections go to 3/16 line - even at the master, so how does what you are saying help anything, or is even possible to do? I also wouldn't want that long residual valve sticking out of my master.

Edited by Powerflite 2020-12-15 4:07 PM
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wizard
Posted 2020-12-15 4:14 PM (#606769 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Also Todd, I don't think that you have air in the system, you confirm that you have a rock hard pedal on the second sttoke. Adjusting the brake shoes to full contact means that ther will be no lash, so first stroke still might be low, but thereafter you should have the same height every time you try the brakes If you get this condition with low pedal on every stroke, then the displacement is too low.
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1960fury
Posted 2020-12-15 5:10 PM (#606770 - in reply to #606768)
Subject: Re: Single circuit to dual circuit



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Powerflite - 2020-12-15 4:05 PM

I'm not following what you are saying Sid. All connections go to 3/16 line - even at the master, so how does what you are saying help anything, or is even possible to do? I also wouldn't want that long residual valve sticking out of my master.


Why do you want to run a 3/16 line between the MC and the residual valve when you can attach it directly to the MC? They ain't that long and It still looks better than a valve in the middle of a brake line and you can use a 90° adapter.
In my car it is attached directly to the prop valve as desribed with a male/male NPT connector but I will change it eventually and move it to the MC.
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1960fury
Posted 2020-12-15 5:19 PM (#606771 - in reply to #606768)
Subject: Re: Single circuit to dual circuit



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I know such things are considered a "No-No" when you work on brake systems, as it is 9/16-18 thread not 20, but it will work anyway. I am a safety neard. Maybe you have to run a 9/16-20 die on it and of course you have to grind off the AN cone.

https://www.ebay.de/itm/Gewindeadapter-1-8-NPT-zu-Dash-6-90-schwarz-...
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samstrader
Posted 2020-12-16 10:11 AM (#606789 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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Todd, I sure enjoyed and learned from the video you posted showing how to bleed and adjust the brakes.
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Todd
Posted 2020-12-16 12:51 PM (#606799 - in reply to #606789)
Subject: Re: Single circuit to dual circuit



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Thanks samstrader. Yes....TECH ist the best of the best. Always ask Tech - he knows :)
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1960fury
Posted 2020-12-16 3:06 PM (#606807 - in reply to #606767)
Subject: Re: Single circuit to dual circuit



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1960fury - 2020-12-15 4:02 PM

Todd - 2020-12-15 3:35 PM

Yes you're right. But Wilwood sell them with inverted 3/8 - 24 adapters to directly install the brake line.


So wouldn't it be more logical and easier to search for, or fabricate a 9/16-20 to 1/8 NPT adapter? Also cleaner looking and a connection that can leak less.

Maybe you can just tap the 9/16 MC tube nut (if there's enough meat) and use a male/male 1/8 NPT to 1/8 NPT connector?


I checked and yes, the MC tube nut is big enough. So you can simply tap it and screw the residual valve directly to the MC with that:



(NPT-elbow.jpg)



Attachments
----------------
Attachments NPT-elbow.jpg (113KB - 240 downloads)
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dplotkin
Posted 2020-12-17 10:12 AM (#606836 - in reply to #606212)
Subject: Re: Single circuit to dual circuit


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Todd:
I posted on the linked thread "spongy brakes" concerning the same problem I had with a 1960 F with front disks and stock drums using a drum/drum master. The drum/drum master will fit under the booster and I have this setup working well in my 61 Plymouth Savoy with later Mopar B body rear drums and GM single piston calipers. Because it worked in the Plymouth I thought it would work in the 300 F. No dice. Same as you - too much travel not enough juice.

Finally employed the taller but shorter Bendix disk/drum master for a 70 Imperial. I cut .700 from the top of the jar & threaded in two screws to hold the lid on. This master is a one inch and an eighth bore and has sufficient volume. Pedal travel is still longer than I would like but it is acceptable.

Try that master - no reason why you cannot use a disk/drum master on a drum/drum setup. Just use a 10 pound residual valve in the front circuit. See the aforementioned thread where I posted photos.

Dan
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Todd
Posted 2020-12-17 11:32 AM (#606839 - in reply to #606836)
Subject: Re: Single circuit to dual circuit



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Hi. Thanks. I purchased a brandnew 1 1/8 bore disc/drum master and installed a 10 psi external wilwood residual valve in the line. The first try did not work as i wrote. But I'll try again. I will bleed the front brake circuit particularly thoroughly and see what happens. But not enough time at the moment. I'm sure I'll do it before Christmas. I won't buy a third MC. If it doesn't work this time, I'll give up. I will report...thanks!!

BTW...The OE line from master to the front tee was 1/4"....maybe that will have the necessary effect to feed the brake 4 front cylinders....maybe it is worth a try too...if 1/4" line will fit to the port of the MC...hmmm....will it fit? Worth a try or not?

Edited by Todd 2020-12-17 12:07 PM
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Todd
Posted 2020-12-17 1:42 PM (#606843 - in reply to #606807)
Subject: Re: Single circuit to dual circuit



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1960fury - 2020-12-16 3:06 PM

I checked and yes, the MC tube nut is big enough. So you can simply tap it and screw the residual valve directly to the MC with that:


Hmmm....how's about this adapter...would it also work? https://wabotech.de/ORFS-Einschraubverschraubung-UNF-9-16-18-AG-NPT-...
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1960fury
Posted 2020-12-17 4:05 PM (#606846 - in reply to #606843)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-17 1:42 PM

1960fury - 2020-12-16 3:06 PM

I checked and yes, the MC tube nut is big enough. So you can simply tap it and screw the residual valve directly to the MC with that:


Hmmm....how's about this adapter...would it also work? https://wabotech.de/ORFS-Einschraubverschraubung-UNF-9-16-18-AG-NPT-...


Yes, good find! But it would make the valve stick out. Since it is 9/16-18 oo it might need a little reworking with a -20 die but it is not aluminum, like the elbow fitting I posted, so it would be even safer.

Edited by 1960fury 2020-12-17 4:14 PM
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samstrader
Posted 2020-12-19 6:20 PM (#606889 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I used this site to buy my 7/16 x 20 Tube Nuts. I went to the page that has Plugs and the BQ 162 is a 7/16 X 20 plug. Would this work? They also have 1/2 x 20. All of my fittings were 7/16 X 20.

Anyway, not sure exactly what you need but these people sure have a lot of this unusual stuff and I was very pleased with what I got from them. Fit perfect.

https://www.mfcp.com/product/fittings/automotive-fittings/plugs-caps...



Edited by samstrader 2020-12-19 6:26 PM
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Powerflite
Posted 2020-12-19 9:36 PM (#606895 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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7/16-20 was used on '55-'56, but the '57-up cars used 7/16-24.
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Todd
Posted 2020-12-26 1:49 PM (#607150 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Merry christmas to all. As for the conversion from the single-circuit to the dual-circuit brake - that's it, i quit! The second attempt didn't work either. Firm pedal only when pumping the pedal. Then if I wait a few seconds, I have to pump again. Even if i adjust the shoes to full contact.
Now I'm looking forward to installing the old single-circuit MC. I'm really looking forward to a firm pedal and good brakes, just like it was before.
Thank you for your involvement and help. I wish you all a happy new year! Thanks, Todd.

Edited by Todd 2020-12-26 1:50 PM
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wizard
Posted 2020-12-26 1:54 PM (#607152 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Sorry Todd, it's a drag after all the work and effort. At least, you confirmed that the displacement of the m/c is insufficiant in the tested ones.

Please make a post of the brand, article number and diameter here
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Todd
Posted 2020-12-27 4:10 AM (#607163 - in reply to #607152)
Subject: Re: Single circuit to dual circuit



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MBM Disc/Dum MC
MC5621
Cast Iron
Original Bendix Style 2225621
1-1/8" Bore
9/16"-20 INV & 1/2"-20 INV
10lb residual valve built in to rear port.
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wizard
Posted 2020-12-27 4:35 AM (#607164 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Thanks' Todd, I assume this is the last dual circuit m/c tested, what about the first one?
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Todd
Posted 2020-12-27 5:31 AM (#607165 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Auto City Classic Drum/Drum Brakes
MC1323
Mopar Bendix Style RPB8001
Manual or Power Applications
1" Bore
9/16"-20 INV & 1/2"-20 INV
W/ Builtin internal residual valves

As for the single MC: Between MC and the tee there is a 1/4" line, i also want to replace, but i don't have the tool to flare 1/4" lines, so i have to order the line - flared with the correct fittings ready to install. The size of those fittings is 7/16-24 UNF (long 20 mm version) BOTH sides, am i right?



Edited by Todd 2020-12-27 9:14 AM
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56D500boy
Posted 2020-12-27 12:15 PM (#607175 - in reply to #607165)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-27 2:31 AM
Auto City Classic Drum/Drum Brakes
MC1323
Mopar Bendix Style RPB8001
Manual or Power Applications
1" Bore
9/16"-20 INV & 1/2"-20 INV
W/ Built-in internal residual valves


Todd: So something like this? Any idea where I could buy just the push-rod accessories? I am going to use a similar Raybestos MC36221 (as shown below):







Edited by 56D500boy 2020-12-27 12:19 PM
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wizard
Posted 2020-12-27 12:39 PM (#607177 - in reply to #607165)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-27 11:31 AM

As for the single MC: Between MC and the tee there is a 1/4" line, i also want to replace, but i don't have the tool to flare 1/4" lines, so i have to order the line - flared with the correct fittings ready to install. The size of those fittings is 7/16-24 UNF (long 20 mm version) BOTH sides, am i right?



I'll try to check this tomorrow Todd
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samstrader
Posted 2020-12-27 1:41 PM (#607183 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I'm sorry it didn't work out Todd. You did great work I think and it is so frustrating when you can't make something work out after working so hard. I can totally relate to your frustration.

Thanks for posting everything because your lessons learned help us all understand how brakes work better and also helps our thinking when considering going to dual master cylinders. I think I'll just stay with my single master now even though I know a dual cylinder is a lot safer.

Sam



Edited by samstrader 2020-12-27 1:46 PM
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Todd
Posted 2020-12-27 1:57 PM (#607186 - in reply to #607175)
Subject: Re: Single circuit to dual circuit



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56D500boy - 2020-12-27 12:15 PM

Todd: So something like this? Any idea where I could buy just the push-rod accessories? I am going to use a similar Raybestos MC36221


If you still have your old single master, you can re-use both, rod and clamp/mounting, both fits to the new MC.

Sam: Thanks a lot Sam, there are all nice and helpful people here, fantastic forum.

Sven: thanks for have a look at the requested thread sizes

Edited by Todd 2020-12-27 2:02 PM
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56D500boy
Posted 2020-12-27 3:52 PM (#607187 - in reply to #607186)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-27 10:57 AM
56D500boy - 2020-12-27 12:15 PM
Todd: So something like this? Any idea where I could buy just the push-rod accessories? I am going to use a similar Raybestos MC36221

If you still have your old single master, you can re-use both, rod and clamp/mounting, both fits to the new MC.


Not if you change the pedal assembly like I am planning. (Needs a clevis at the pedal end like the original 55 Mopar PB/MC combo had).



Edited by 56D500boy 2020-12-27 5:10 PM
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Powerflite
Posted 2020-12-27 7:53 PM (#607195 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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You can get things like that at Summit.
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wizard
Posted 2020-12-28 7:52 AM (#607202 - in reply to #607165)
Subject: Re: Single circuit to dual circuit



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Todd - 2020-12-27 11:31 AM

As for the single MC: Between MC and the tee there is a 1/4" line, i also want to replace, but i don't have the tool to flare 1/4" lines, so i have to order the line - flared with the correct fittings ready to install. The size of those fittings is 7/16-24 UNF (long 20 mm version) BOTH sides, am i right?



Ok Todd, just checked; the 1/4" fittings are both male 7/16"-24 UNF and 3/3" (approx 20 mm) long will work just fine.
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Todd
Posted 2020-12-28 10:08 AM (#607206 - in reply to #607202)
Subject: Re: Single circuit to dual circuit



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Thanks so much Sven!
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Powerflite
Posted 2021-01-03 2:55 AM (#607350 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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I just finished bleeding the brake system on my '56 Fury with front discs, original rear drums & a 1.032" dual disc brake master. It has a solid, high pedal now with about 1.5" of travel. The only issue is the pedal is firm even with the rear bleeders open. The rear brake hose must have plugged itself off, but was open enough to allow the air to escape past it while under pressure.
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Todd
Posted 2021-01-18 9:48 AM (#607839 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Hi Guys. Finally, I would like to contact you again on this topic. I have now reinstalled the single-circuit master and immediately had the good feeling of a firm and rock solid pedal. This is the final proof that a two-circuit master does not work on a car with drums all around - not even if it has the same bore size. At least not if the car has six wheel brake cylinders. Now I have a single circuit brake system again with new components. I overhauled the master, the brake lines are all new and the wheel brake cylinders are all new too. A tedious experience, but in the end I am happy that everything is working properly again. Thank you to everyone who shared my thoughts on this topic and wanted to help. Best wishes, Todd

Edited by Todd 2021-01-18 9:52 AM
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wizard
Posted 2021-01-18 11:52 AM (#607842 - in reply to #601590)
Subject: Re: Single circuit to dual circuit



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Great Todd! Now you must maintain your brake system. Change the brake fluid every two years if you use DOT3. That will prevent rust issues. Or use DOT5, but then you must clean out the DOT3 or 4 from the system.
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samstrader
Posted 2021-01-23 2:04 AM (#608062 - in reply to #601590)
Subject: Re: Single circuit to dual circuit


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I'm glad everything is working again Todd.... Congratulations. I also appreciate your work and documentation because it applies to my car 100 percent. I'll know what to do with mine now.

Sam
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