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rod knock in my 241 hemi
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dodge59
Posted 2013-06-02 7:46 PM (#378612)
Subject: rod knock in my 241 hemi



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sounds like my 241 hemi has come up with a rod knock.. does not make noise until rps are up there .

I noticed it today taking a road trip to a car show and heard it knocking at 55 mph . mostly between 50 and 60 mph .

would it be possible to drop the pan and install new bearings or......?

just what I need to start the summer off.

Edited by dodge59 2013-06-02 7:50 PM
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d500neil
Posted 2013-06-02 8:27 PM (#378625 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



Exner Expert 19,174 posts. Neil passed away 18 Sep 2015. You will be missed, Neil!

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Location: bishop, ca
John, you can look on the bright side [of life; M. Python] and go buy some nasty condition 50's distributor, or go sweet-
talk Big M, here, into selling/giving you a parts-dissie's light weight return spring.

That spring will allow your car's OEM dissie to increase its advance rate, quickly, for faster acceleration.

Then, because your IAZ 4003F dissie has dual points in it, you can buy Pertronix's "Ignitor 1383" hidden-under-cap
electronic ignition and install it, for overall better reliability and better MPG (hotter spark) than the IAZ guy provides.

With both the lighter weight spring and the 1383, you can dial in about 8/9 degrees of engine-advance (instead of the
wimpy 4-degrees of OEM-advance), to get you 8/9 + 24(built-in Mechanical Advancement)= 32/33 degrees of total
Mechanical advancement + 14 degrees of OEM Vacuum Advancement = 46/47 degrees of Total Advancement.

Hopefully, your OEM V.A. still works; suck on its orifice to hear/feel if its diaphram is moving, and check out the dissie's
shaft bearing condition, too.





Edited by d500neil 2013-06-02 8:32 PM
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ttotired
Posted 2013-06-02 8:35 PM (#378628 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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Neil

What has all that really great dizzy info have to do with the poor bloke suspecting he has a stuffed big end bearing?

Anyway, If it has developed a big end knock, from what I have seen, it most likely will have damaged the bearing surface a bit.

Obviously, cant tell till the pan is off and the cap removed, but I think you would be very lucky to get away with just a set of bearings

Sorry

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d500neil
Posted 2013-06-02 8:58 PM (#378637 - in reply to #378628)
Subject: Re: rod knock in my 241 hemi



Exner Expert 19,174 posts. Neil passed away 18 Sep 2015. You will be missed, Neil!

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What's it got to do is simply this: while his/your car is 'down' he/you can make other repairs and upgrades to it
without otherwise losing driving time, during its repair time.



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dodge59
Posted 2013-06-02 9:42 PM (#378639 - in reply to #378625)
Subject: Re: rod knock in my 241 hemi



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d500neil - 2013-06-02 7:27 PM

John, you can look on the bright side [of life; M. Python] and go buy some nasty condition 50's distributor, or go sweet-
talk Big M, here, into selling/giving you a parts-dissie's light weight return spring.

That spring will allow your car's OEM dissie to increase its advance rate, quickly, for faster acceleration.

Then, because your IAZ 4003F dissie has dual points in it, you can buy Pertronix's "Ignitor 1383" hidden-under-cap
electronic ignition and install it, for overall better reliability and better MPG (hotter spark) than the IAZ guy provides.

With both the lighter weight spring and the 1383, you can dial in about 8/9 degrees of engine-advance (instead of the
wimpy 4-degrees of OEM-advance), to get you 8/9 + 24(built-in Mechanical Advancement)= 32/33 degrees of total
Mechanical advancement + 14 degrees of OEM Vacuum Advancement = 46/47 degrees of Total Advancement.

Hopefully, your OEM V.A. still works; suck on its orifice to hear/feel if its diaphram is moving, and check out the dissie's
shaft bearing condition, too.





neil
That is exactly what I am going to do with the other improvements I asked about previously in other posts .. Thanks again !

Edited by dodge59 2013-06-02 9:42 PM




(hemi all painted with 4 bl 40%.JPG)



Attachments
----------------
Attachments hemi all painted with 4 bl 40%.JPG (178KB - 780 downloads)
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dodge59
Posted 2013-06-02 9:45 PM (#378640 - in reply to #378637)
Subject: Re: rod knock in my 241 hemi



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d500neil - 2013-06-02 7:58 PM

What's it got to do is simply this: while his/your car is 'down' he/you can make other repairs and upgrades to it
without otherwise losing driving time, during its repair time.





right neil !
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58coupe
Posted 2013-06-03 11:09 AM (#378734 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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dodge59, If what you are hearing is indeed a rod knock, it has been my experience that by the time you hear it the crank is probably already scored but you can try to drop the pan and change the bearings.
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60 dart
Posted 2013-06-03 4:44 PM (#378777 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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with a rod knock , you'd be lucky to not need a new or diff, crank but possibly it could be a wrist pin knock ----------------------------------------------------later
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Shep
Posted 2013-06-03 7:39 PM (#378807 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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All guess work until some pulls the pan and checks the lower end, then we can give some meaningful advice.
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dodge59
Posted 2013-06-03 8:41 PM (#378816 - in reply to #378807)
Subject: Re: rod knock in my 241 hemi



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Shep - 2013-06-03 6:39 PM

All guess work until some pulls the pan and checks the lower end, then we can give some meaningful advice.


well.... here we go...........

Got the pan down and #8 cyl rod bearing was sloppy

had the speed shop here help me out with what I need to do.. he says the correct way to do it would be to rebuild the whole engine.. well.........
appears a 30 thousandths under bearing will cure the knock.. no telling how long it would last but will to give it a shot. .. The crank was not scored anywhere. hopefully I caught it time with just a bearing replaement.
I miced up the crank journal and it was 1.9055 + or -
standard shaft diameter is 1.936-1-1.937 so.. 30 thousandths under should work fine.


john
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dodge59
Posted 2013-06-03 9:13 PM (#378823 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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anyone know where I can purchase the rod bearings for the 241 hemi ? seen one on ebay and hothemiheads so far.

Edited by dodge59 2013-06-03 11:54 PM
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d500neil
Posted 2013-06-04 2:21 AM (#378862 - in reply to #378823)
Subject: Re: rod knock in my 241 hemi



Exner Expert 19,174 posts. Neil passed away 18 Sep 2015. You will be missed, Neil!

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http://hothemiheads.com/

Or:


http://www.egge.com/



Edited by d500neil 2013-06-04 2:23 AM
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Mopar1
Posted 2013-06-04 5:49 AM (#378876 - in reply to #378862)
Subject: Re: rod knock in my 241 hemi



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"Wayfarer" here on the Board is Quality Engeneereed Components, check with him. also maybe Rock Auto, NAPA.
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Shep
Posted 2013-06-04 9:45 AM (#378909 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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Better check that #8 rod carefully.
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dodge59
Posted 2013-06-04 11:14 AM (#378933 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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Thanks guys !
napa $160 . hothemiheads $140 , ebay $100.00 .. and egge nothing for the 241 hemi

shep.
I will check the #8 rod

Edited by dodge59 2013-06-04 11:16 AM
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dodge59
Posted 2013-06-04 11:41 AM (#378937 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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ordered bearings and gaskets up from ebay user falconglobal..
Thanks everyone !
john
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Mopar1
Posted 2013-06-04 6:23 PM (#378992 - in reply to #378933)
Subject: Re: rod knock in my 241 hemi



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dodge59 - 2013-06-04 10:14 AM

Thanks guys !
napa $160 . hothemiheads $140 , ebay $100.00 .. and egge nothing for the 241 hemi

shep.
I will check the #8 rod
Check directly(call) QEC, he has stuff that's not on the site.
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ttotired
Posted 2013-06-04 8:33 PM (#379013 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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This sounds strange to me

How does a crank big end bearing jernal shrink by 30 thou and remain round and not pound the crap out of the bearing?

Do you think maybe, that bearings may have been mixed up somehow during recent a rebuild?

Most times (not all) they do not re size conrod sizes, they only change the crank size, so I would think that if the conrod big end is larger than std, that the hole (with the cap tightened to the rod) could be egg shaped and a new rod would be in order.

I spun a big end bearing in an old mark 1 ford escort once and tried just changing the rod and a bearing (I got a 10 thou one) and when I started it, it went for about 3 min and started knocking again (that was the end for that car, it was a cheapy anyway).

As much as a rebuild is not cheap (having just done my poly), a broken rod and a hole in the side of the block on a hemi (look in earlee Bobs thread on his desoto) would be almost catastrophic.

I know this is not what you would like to hear, but the costs of a crank re grind and a set of crank bearings ect is a lot cheaper than an entire engine and you most likely will get away with not having to do the top end (if that was ok before), but whatever way you go, triple check your oil galleries, as its really strange for 1 bearing to go if it did not loose oil.

Food for thought

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VAN HELSING
Posted 2013-06-04 9:00 PM (#379023 - in reply to #378816)
Subject: Re: rod knock in my 241 hemi



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dodge59 - 2013-06-04 11:41 AM

Shep - 2013-06-03 6:39 PM

All guess work until some pulls the pan and checks the lower end, then we can give some meaningful advice.


well.... here we go...........

Got the pan down and #8 cyl rod bearing was sloppy

had the speed shop here help me out with what I need to do.. he says the correct way to do it would be to rebuild the whole engine.. well.........
appears a 30 thousandths under bearing will cure the knock.. no telling how long it would last but will to give it a shot. .. The crank was not scored anywhere. hopefully I caught it time with just a bearing replaement.
I miced up the crank journal and it was 1.9055 + or -
standard shaft diameter is 1.936-1-1.937 so.. 30 thousandths under should work fine.


john




.....

Hope I'm not reading this wrong but ...........

You'd be VERY lucky if it was such a quick fix as just replacing a bearing and be on your way especially for many miles to come.

Are they talking, get a 30 thou under bearing and just fitting it to the existing crank as is ?? whack on the pan and drive away?

It'd be a fix maybe if you were in the middle of no-where and just had to get back on your way but for long term driving I'd be checking and doing a lot more than just that.

30 thou is a lot of wear when we are talking this sort of stuff.

Did the shop that checked your crank check it for ovality and taper ? . Usually when a bearing knocks to that point is has ( as ttotired said ) pounded and worn the upper TDC area and lower BDC area of the crank because of the piston reciprocation direction changes where the bearing and crank pin is subject to it's highest loadings ( especially TDC on firing ). This creates ovality on the crank pin.

All engines I have ever worked on presenting a bearing knock have had crank pin ovality that can only be rectified by machining, or pin welding and re-machine ( expensive ) or a replacement crank.

It even happens on engines showing no knocking symptoms.

As far as a re-build that the shop advises , yeah , maybe, but sometimes rebuild may not always be necessary, sometimes just a refresh will do. Won't know until a tear down and measure of parts.

Perhaps if in doubt it may pay to completely rebuild as labor cost would only be a bit cheaper for a refresh compared to a rebuild.


............
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Shep
Posted 2013-06-05 9:29 AM (#379103 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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Hard to believe any decent shop would recommend resizing only one journal especially on an old engine that surely has some clean up necessary on the rest, we hope!!
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Mopar1
Posted 2013-06-05 10:25 AM (#379115 - in reply to #379103)
Subject: Re: rod knock in my 241 hemi



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241s aren't known for overly strong cranks in high performance situations. You should have all the journals turned the same amount & check the mains while it's out. Add a damper while you're @ it.
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firedome
Posted 2013-06-05 10:45 AM (#379124 - in reply to #379115)
Subject: Re: rod knock in my 241 hemi



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In fact 241s and early hemis in general were farily notorious for broken crankshafts.
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davewilkes
Posted 2013-06-05 12:27 PM (#379156 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi


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Is it just one journal that is 30 under or has the crank been turned to 30 under at some point and that is the size of all journals. If that is the case then it appears that the bearing took all of the wear and started knocking. I would put the new bearing in if all journals were at 30 under and there was no scoring. If it starts to knock again then your in for a rebuild. But you will know fairly quickly if the repair will work or not.
I have got away with a single bearing replacement on probably about 5 engines (one was a large diesel tractor) and they all kept going for years. But I have also had 2 that didn't work out. One was a 351, 73 Ford LTD and the other a 21 Model T.
Worth the try in my opinion if there is no scoring on the crank.
Dave
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wbower3
Posted 2013-06-05 12:54 PM (#379160 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi


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I'd dayum sure pull the caps off the other 7 rods, and maybe even the front and rear main bearings to see what they looked like before I changed one (1) rod bearing..... But I didn't start building engines until about 1948, and I'm sure those kids in the local speed shop have more experience.



Edited by wbower3 2013-06-05 12:55 PM
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dodge59
Posted 2013-06-05 1:27 PM (#379170 - in reply to #379013)
Subject: Re: rod knock in my 241 hemi



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ttotired - 2013-06-04 7:33 PM

This sounds strange to me

How does a crank big end bearing jernal shrink by 30 thou and remain round and not pound the crap out of the bearing?

Do you think maybe, that bearings may have been mixed up somehow during recent a rebuild?

Most times (not all) they do not re size conrod sizes, they only change the crank size, so I would think that if the conrod big end is larger than std, that the hole (with the cap tightened to the rod) could be egg shaped and a new rod would be in order.

I spun a big end bearing in an old mark 1 ford escort once and tried just changing the rod and a bearing (I got a 10 thou one) and when I started it, it went for about 3 min and started knocking again (that was the end for that car, it was a cheapy anyway).

As much as a rebuild is not cheap (having just done my poly), a broken rod and a hole in the side of the block on a hemi (look in earlee Bobs thread on his desoto) would be almost catastrophic.

I know this is not what you would like to hear, but the costs of a crank re grind and a set of crank bearings ect is a lot cheaper than an entire engine and you most likely will get away with not having to do the top end (if that was ok before), but whatever way you go, triple check your oil galleries, as its really strange for 1 bearing to go if it did not loose oil.

Food for thought



this hemi has 72k original miles on it.. pretty slugged up inside.. when I took the pan off there waere no shaving or pieces .. seen just a little silver in one area ,, but there was a half inch of sludge on the bottom of the pan in the deepest area. last owner told me this car sat in storage for 20 + years .. that is what usually happens to oil when it sits for 20 years .

The speedshop hasn't seen the engine except for the rodcap and bearings off #8 cyl.. they don't recommend doing a quick fix to any engine.. I'm the one trying fix the issue without going thru a complete rebuild .. I just don't have 5k to blow right now.
the speed shop told me that rod bearing spun .. I miced the rod journal and .030 would bring it back to spec. that's why so much material off the bearing .

Edited by dodge59 2013-06-05 1:49 PM
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ttotired
Posted 2013-06-05 6:46 PM (#379213 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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Just would hate to see you throw away good money and time on a fix that, if your lucky, will last a week or 2.

I am sure that a set of bearings and a crank re grind will not cost you 5000, but its your engine and to do the crank is a lot of work.

Do you think it might be a good idea to get an engine machine shop to measure your con rod?

If the bearing spun, theres a good chance the big end is not the right size (or shape) anymore

Best of luck

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dodge59
Posted 2013-06-05 8:20 PM (#379244 - in reply to #379213)
Subject: Re: rod knock in my 241 hemi



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ttotired - 2013-06-05 5:46 PM

Just would hate to see you throw away good money and time on a fix that, if your lucky, will last a week or 2.

I am sure that a set of bearings and a crank re grind will not cost you 5000, but its your engine and to do the crank is a lot of work.

Do you think it might be a good idea to get an engine machine shop to measure your con rod?

If the bearing spun, theres a good chance the big end is not the right size (or shape) anymore

Best of luck



kind of hard to measure the rod ends when they are still in the engine and working on my back with the car up on jack stands with the oil pan off.
going to roll the dice on this one . 50 -50 chance it may hold together.
yes ....... as I mentioned it did spin that bearing... I'm going to remove all the
other caps and see what they look like and mic them all up.. maybe someone has done some work in there before .

Edited by dodge59 2013-06-05 8:28 PM
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Shep
Posted 2013-06-06 9:11 AM (#379373 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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If the bearing spun in the rod, do not just reuse that rod, period!
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VAN HELSING
Posted 2013-06-06 7:30 PM (#379463 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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..........




I completely understand your position with funding, I too weigh up the cost of this and that as opposed to a cheaper alternative nearly all the time, bills, mortgage and the cost of living causes this default option over the years.

Some repair situations can work out OK by sticking with a cheaper and less time consuming plan and others won't.

Based on what I'm reading, and if I'm reading it correctly, I just don't think the repair direction you may be looking at ( or your machine shop ) is going to work for very long if at all.

The apparent 30 thou wear on the crank is a hell of a lot or wear.

It may work, but I feel there is a slim chance of that.

At the very bare minimum if it were my engine, I'd pull it and remove and check all crank journals and rods and go from there.

Like others have said , I'd hate to see you flinging money and time around for a quick fix only to find it may not work and your money is wasted. Granted, there is a slim chance it may be OK, but if not, the money to date would go a fair way towards a fix that will ease your mind knowing that you should have more reliable engine from it.

If it works, great , and I'm happy to eat my words, humble pie don't taste too bad I'm told

Good luck with what ever direction you take.

......


....

Edited by VAN HELSING 2013-06-06 7:31 PM
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ttotired
Posted 2013-06-06 7:32 PM (#379465 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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I really do wish you the best of luck with it

I dont really think its 50/50, but I have seen others get away with stuff that I know, if I did it, would come back and bite me.

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dodge59
Posted 2013-06-06 7:56 PM (#379472 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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Thank you guys for all your feedback ........ sure do appreciate it.

I'm looking at it this way .. it cost me $100 for bearings and a gasket .. either it works or doesn't work . I can live with that.

another thought was , Say I go ahead and do the crank, rods and new bearings and it happens again because of oil starvation ..( maybe oil galleries plugged or what ever.) I'd be more ticked off after spendings That $$ vs just replacing that bad bearing.. .

another alturnative would be to purchase another redram 241 that is still running good and install it for now. imo.

anyway .... I'll see where this goes as soon as I see what the other bearing look like .


Edited by dodge59 2013-06-06 7:59 PM
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JT Vincent
Posted 2013-06-07 1:23 PM (#379604 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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I'm a little confused. You have the crank out now? Why not get it turned and replace the bearings to turned spec, and maybe change your compression and oil control rings while you're there? You could also run the oil pump with the crank out and see if #8 is getting fed. It's a little more work for a more comprehensive job.
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dodge59
Posted 2013-06-07 7:03 PM (#379663 - in reply to #379604)
Subject: Re: rod knock in my 241 hemi



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JT Vincent - 2013-06-07 12:23 PM

I'm a little confused. You have the crank out now? Why not get it turned and replace the bearings to turned spec, and maybe change your compression and oil control rings while you're there? You could also run the oil pump with the crank out and see if #8 is getting fed. It's a little more work for a more comprehensive job.


jt
the engine and crank all assembled still with the pan off and number 8 rod cap and bearing off. that's it.
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dodge59
Posted 2013-06-08 11:47 PM (#379874 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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update .

installed the .030 under bearing in #8 and could not move the crank .. it would not budge.

so............ guess the rod journal is egg shaped... engine is ready to come out .. may just do the crank, rods and bearing , can't afford a complete rebuild now. we'll see $$.

anyone out there have a nice running 241 - 270 hemi redram for sale ? othwise she is going to the repair shop.
thanks !
john

Edited by dodge59 2013-06-08 11:49 PM
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Mopar1
Posted 2013-06-09 8:56 AM (#379906 - in reply to #379874)
Subject: Re: rod knock in my 241 hemi



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Another thing to consider while saving up your $s is the C/R. At 241 you're looking at tiny displacement & low C/R. The nominal C/R is 7 or 7.1:1, patheticly low, & one 241 was measured at an actual 6.19:1 It would be worth the investment to get custom forged pistons in the 9 or 10:1 area.
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dodge59
Posted 2013-06-09 11:31 AM (#379917 - in reply to #379906)
Subject: Re: rod knock in my 241 hemi



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Mopar1 - 2013-06-09 7:56 AM

Another thing to consider while saving up your $s is the C/R. At 241 you're looking at tiny displacement & low C/R. The nominal C/R is 7 or 7.1:1, patheticly low, & one 241 was measured at an actual 6.19:1 It would be worth the investment to get custom forged pistons in the 9 or 10:1 area.


that would increase hp and tq for sure which it needs ,, but on the other hand I like to get descent gas mileage for this cruiser . I get 24 mpg now with the hemi , would that suffer then ?

off hand .......do you know who might carry higher compression pistons ?
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Mopar1
Posted 2013-06-09 12:56 PM (#379929 - in reply to #379917)
Subject: Re: rod knock in my 241 hemi



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dodge59 - 2013-06-09 10:31 AM

Mopar1 - 2013-06-09 7:56 AM

Another thing to consider while saving up your $s is the C/R. At 241 you're looking at tiny displacement & low C/R. The nominal C/R is 7 or 7.1:1, patheticly low, & one 241 was measured at an actual 6.19:1 It would be worth the investment to get custom forged pistons in the 9 or 10:1 area.


that would increase hp and tq for sure which it needs ,, but on the other hand I like to get descent gas mileage for this cruiser . I get 24 mpg now with the hemi , would that suffer then ?

off hand .......do you know who might carry higher compression pistons ?
Pistons could be had from Hot Heads or Quality Engineered Components("Wayfarer" here on the Board), theres others also. Interesting Question! Right now the 6-7 C/R isn't very efficient, but you probably can run Sunoco 85 w/o a problem. 9:1 pistons should give a good increase in HP and reduce the strain of getting her moving off the stop light. Would probably need a little hotter grind cam. Would still burn same octane gas @ 9:1 that a wedge would burn @ 8:1.
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d500neil
Posted 2013-06-09 5:11 PM (#379952 - in reply to #379929)
Subject: Re: rod knock in my 241 hemi



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Higher compression ratios provide for better MPG, by getting a tighter squeeze on the air/fuel mixture.

With 9:1 slugs, you should be able to use 87 octane regular gas.

Regular gas has more hydrocarbons (what you actually BURN), by volume, than do the higher grade gasses, which have anti-knock,
etc., agents in them, so, regular gas has intrinsically more 'power' in it than does (anti-knock-additive) "High Test" gasoline.

Your distributor advancements will also control the performance and the MPG of the car.

A mild cam grind will also help in your performance and MPG.

Forged pistons are needed for supercharged engines; cast pistons will do you just fine---they're lighter, too.








Edited by d500neil 2013-06-09 5:14 PM
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Mopar1
Posted 2013-06-09 7:52 PM (#379975 - in reply to #379952)
Subject: Re: rod knock in my 241 hemi



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d500neil - 2013-06-09 4:11 PM

Forged pistons are needed for supercharged engines; cast pistons will do you just fine---they're lighter, too
I suspect that cast pistons above the OEM 7:1 aren't available, though I haven't actually looked. Unless Jahn's made them back in the day & a set was to turn up.
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d500neil
Posted 2013-06-09 8:33 PM (#379984 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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I got cast pistons in my 40-over 325; figure that that works out to something like 330 c.i.

That was 15(??) years ago.



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dodge59
Posted 2013-06-09 10:04 PM (#379989 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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update on the rod knocker

hemi is out of the car . not too bad of a job. I must say.

I'm thinking of doing like some of you guys said to do .... that is....... just do the lower end ... flip it over , pull the crank , pistons rods resize everything that is needed and install new main and rod bearings.
quick fix that will last i would think . good idea or not?

I kept asking my speed shop how much it would cost to do the lower end and can never get a straight answer from him .. says it all depends .. what do you guys think it should cost to do the lower end over ? that's for them to do all the machine work only .. turn the crank . resize the rods........ etc .......
I can reasemble the engine.

john

Edited by dodge59 2013-06-09 10:18 PM




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Mopar1
Posted 2013-06-09 10:26 PM (#379992 - in reply to #379989)
Subject: Re: rod knock in my 241 hemi



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If you were happy with performance & it wasn't smoking, go for it.
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dodge59
Posted 2013-06-09 10:38 PM (#379994 - in reply to #379992)
Subject: Re: rod knock in my 241 hemi



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Mopar1 - 2013-06-09 9:26 PM

If you were happy with performance & it wasn't smoking, go for it.


I'm very happy with the improvements I made before the rod knock started.. had a bunch more power with adding the dual exh and 4bl intake & carb .. not looking for a race car ... I have a 11 sec race car already.

question for you guys ::

say I went with high compression pistons , wouldn't I need different length rods then. ?? .. also would I be able to do this install for the bottom end without takng the heads off ? It just can't be that easy could it?

Edited by dodge59 2013-06-09 10:58 PM
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d500neil
Posted 2013-06-09 11:28 PM (#380004 - in reply to #379994)
Subject: Re: rod knock in my 241 hemi



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What is your shop's hourly labor rate?

Around here, its +/- $100bux

Spend the money; do it once & do it right [-Kanter].







Edited by d500neil 2013-06-09 11:29 PM
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Mopar1
Posted 2013-06-10 8:56 AM (#380055 - in reply to #379994)
Subject: Re: rod knock in my 241 hemi



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dodge59 - 2013-06-09 9:38 PM

I'm very happy with the improvements I made before the rod knock started.. had a bunch more power with adding the dual exh and 4bl intake & carb .. not looking for a race car ... I have a 11 sec race car already.

question for you guys ::

say I went with high compression pistons , wouldn't I need different length rods then. ?? .. also would I be able to do this install for the bottom end without takng the heads off ? It just can't be that easy could it?
A 241 CID engine would hardly make it a race car. It'd bring the engine into the modern era, comp wise. The C/R is increased by adding a dome to the piston. If just changing the bearings you could probably just change out the crank w/o removing the heads. Where you're talking replacing or resizing a rod you'll have to take off the head on that bank to use a ring compressor to get the piston back in.
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dodge59
Posted 2013-06-10 11:30 AM (#380093 - in reply to #380055)
Subject: Re: rod knock in my 241 hemi



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Mopar1 - 2013-06-10 7:56 AM

dodge59 - 2013-06-09 9:38 PM

I'm very happy with the improvements I made before the rod knock started.. had a bunch more power with adding the dual exh and 4bl intake & carb .. not looking for a race car ... I have a 11 sec race car already.

question for you guys ::

say I went with high compression pistons , wouldn't I need different length rods then. ?? .. also would I be able to do this install for the bottom end without takng the heads off ? It just can't be that easy could it?
A 241 CID engine would hardly make it a race car. It'd bring the engine into the modern era, comp wise. The C/R is increased by adding a dome to the piston. If just changing the bearings you could probably just change out the crank w/o removing the heads. Where you're talking replacing or resizing a rod you'll have to take off the head on that bank to use a ring compressor to get the piston back in.


mopar1
so..... IF I have to take take the rods and pistons out the heads have to come off? pistons have to come in from the top and can't come in from the bottom end?
Tha'ts what I thought.. well I an see This is going to snowball into a full blown rebuild when I get started . $$$$$$$$$
There is no easy simple cheap fix I guess.


Edited by dodge59 2013-06-10 11:33 AM
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dodge59
Posted 2013-06-10 1:06 PM (#380117 - in reply to #378612)
Subject: Re: rod knock in my 241 hemi



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who else might carry these high compression pistons for the 241 hemi everyone is talking about ?
hot hemiheads wants $800+ ............ and QEC won't answer there phones.
Thanks !
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Mopar1
Posted 2013-06-10 3:02 PM (#380142 - in reply to #380117)
Subject: Re: rod knock in my 241 hemi



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dodge59 - 2013-06-10 12:06 PM

who else might carry these high compression pistons for the 241 hemi everyone is talking about ?
hot hemiheads wants $800+ ............ and QEC won't answer there phones.
Thanks !
Yeah, nothing is cheap about these engines. QEC is "Wayfarer" here, PM him, and he's "73RR" on the HAMB, could try PMing him there. There's a place in Jacksonville, Fla that has a lot of new hemi stuff on EBay, could look them up & see what they think of there stuff. The cheap way of doing it is dropping in a 318LA/904 and a modern axle.
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Mopar1
Posted 2013-06-10 3:04 PM (#380143 - in reply to #380093)
Subject: Re: rod knock in my 241 hemi



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dodge59 - 2013-06-10 10:30 AM

mopar1
so..... IF I have to take take the rods and pistons out the heads have to come off? pistons have to come in from the top and can't come in from the bottom end?
Tha'ts what I thought.. well I an see This is going to snowball into a full blown rebuild when I get started . $$$$$$$$$
There is no easy simple cheap fix I guess.
You can't use a ring compressor on the bottom.
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d500neil
Posted 2013-06-10 5:58 PM (#380177 - in reply to #378612)
Subject: RE: rod knock in my 241 hemi



Exner Expert 19,174 posts. Neil passed away 18 Sep 2015. You will be missed, Neil!

Posts: 19146
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In 53-54, Hudsons were the car to beat, but in 53-56, Dodge's 'little' Hemi acquitted itself very nicely, in the typically
underdog-to-Chubbie drivers, in NASCAR competition.





Edited by d500neil 2013-06-10 6:01 PM




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