The Forward Look Network
The Forward Look Network
Search | Statistics | User Listing Forums | Chat | eBay | Calendars | Albums | Skins | Language
You are logged in as a guest. ( logon | register )

Defective Water Temperatur Sensor
Jump to page : 1
Now viewing page 1 [50 messages per page]
View previous thread :: View next thread
   Forward Look Technical Discussions -> Electrical, Battery and ChargingMessage format
 
sermey
Posted 2010-02-22 6:21 PM (#211170)
Subject: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND

I just swapped to a new Water Pump System. I didn't replaced the Water Temperatur Sensor for keeping the same Temperature Value on the gauge. All was running as expected, just the Temperature Gauge didn't showed anything at normal warmed engine. The voltage Regulator had the correct Voltage, and the Fuel Gauge worked correctly. It should be the Water Temperatur Sensor.

Checking the resistor, it was infinite - no resistance at all. Then I turned the Contact during measurement, and suddenly I could read a value. I heated the Sensor, and the resistance dropped as it should be. Gladly I mounted it on the Water Pump and thought this problem now is solved. But the Temperature Gauge stopped at about 10%. Now I wanted to know exactly the needed Resistance Value of the sensor for a 60% display. I supplied the Temperature Gauge on a spare instruments panel with 5 Volt, and adjusted a resistor to get the desired value (sensor simulation):

Voltage = 5.0V  Resistor = 22 Ohm Current = 140 mA  (for '59 Dodge Custom Royal, 361))

On the car I substituted the sensor  by this Resistor of 22 Ohm and got as expected a 60% reading. Now I checked the Water Pump Sensor in Water and boiled up. 60 Ohm was the lowest value when boiling, means there is an additional residual resistor of 38 Ohm limiting a higher reading.. At boiling water I turned the contact until I got the minimum of 20 Ohm, the internal contact to the temperature sensitive  device was "cleaned". Now my Temperature Gauge shows the correct value.

The experience: No need to remove the Water and the Temperature Sensor. Just turn the connector of the sensor at hot temperature till normal (max) reading. The isolating "semi-conductor" has been removed, the Water Temperatur Sensor is "repaired". This is not engineering, just "help yourself" . - SERGE -   :laugh: 



Edited by sermey 2010-02-22 6:31 PM




(Sensor Simulation LL.jpg)



Attachments
----------------
Attachments Sensor Simulation LL.jpg (83KB - 317 downloads)
Top of the page Bottom of the page
59CRL
Posted 2010-02-22 7:43 PM (#211190 - in reply to #211170)
Subject: RE: Defective Water Temperatur Sensor



Expert

Posts: 2679
2000500100252525
So your saying a properly working sensor should show a reading of 60% on the gauge..... I think that is right, mine shows like 75% with a new sensor.
Very good troubleshooting. Maybe you just need a new sensor.
Top of the page Bottom of the page
wizard
Posted 2010-02-23 12:42 AM (#211240 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
This is very interesting Serge! I didn't even know that you could turn the connector at all. You are refering to the small brass "nail" in the centre of the sensor? I also have this kind of problem with my temperature gauge circuit - never showing the actual teperature reading.
Top of the page Bottom of the page
sermey
Posted 2010-02-23 1:59 AM (#211251 - in reply to #211190)
Subject: RE: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND

59CRL:  Maybe you just need a new sensor.

Greg, f the reading remain stable I don't think so. I imagine by turning I "cleaned"inside the junction. This must be very good and have 0 Ohm at the hot resistor value of 22 Ohm. At very hot engine, or  for a 100% reading it must  go down to 18 Ohm, At room temperature the sensor has 145 Ohm. Of course, there is no guaranty that this works for ever. Any changements I will report here.

Before I was looking for a replacement, didn't found one with 3/8" with the indication of the resistance at ambient temperature. I have already a new spare sensor. But this one, as I tested now, indicates a much higher resistance, there is no reading at all on the instrument. Where can I get a replacement with 145 Ohm? I found at one Summit and at Year One, also with no value indication, but about 1/4" longer than the one used in the '59 Dodge (they say for all cars, for 1960 up?), I guess it is the same I have already with a too high value.

The resistance of your 1959 Sensor, Greg?

__________________________________________

wizard:  I also have this kind of problem with my temperature gauge circuit - never showing the actual temperature reading.

Sven, I was already thinking of your problem mentioned in an other thread. You stated, by adding a serial resistor the instruments reading can be reduced - I would rather say "limited". But for increasing the reading there is no other way than to replace the sensor or to increase the voltage of the regulator (only for the Temp Gauge!). I am curious to read your results. This proceeding can be done directly on the idling engine.

Attention: Don't short-circuit to ground. The gauge will go up to over 100%, after a longer exposure it may change in reduced sensitivity by overheating!  - SERGE -

The resistance of your 1960 Sensor, Sven? 



Edited by sermey 2010-02-23 8:34 AM
Top of the page Bottom of the page
sermey
Posted 2010-02-23 2:13 AM (#211255 - in reply to #211240)
Subject: Re: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND
I  found a drawing with the interior of the unit. This can explain the contact between the bad connector and the spring. By turning, this junction will be "cleaned".


Edited by sermey 2010-02-23 7:36 AM




(Temperature Sender Unit LL.jpg)



Attachments
----------------
Attachments Temperature Sender Unit LL.jpg (67KB - 605 downloads)
Top of the page Bottom of the page
wizard
Posted 2010-02-23 12:45 PM (#211304 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
Serge, I'm out on a service intervention - I'll try to measure the resistance (cold) when I get home and/or see if I can find my notes about the resistance while hot (on the stove in hot water). Thanks for the picture of the sending unit - that really explains everything - clearly there could be bad contact between the spring and the terminal.
Top of the page Bottom of the page
JimK
Posted 2010-02-23 6:01 PM (#211337 - in reply to #211170)
Subject: RE: Defective Water Temperatur Sensor



Veteran

Posts: 259
1001002525
Location: Detroit MI area
My 57 Chrysler has gone through two temperature sending units over the years. This all came with
drama about checking the wires and gauge but with no results. It was always the sending unit. I have had some results by twisting the "nail" tip as noted above. Eventually all have gone intermittent and only work when they want to, then not at all.

On replacement sending units...I had two replacements that would read 3/4 toward "Hot" from a cold start.
It would go to full Hot with the engine only warm, so a different resistance value. My usually reliable and well known sources claimed these were the right sending units. With the old unit broken I had nothing to compare to! Not scientific at all, but I found the replacement sending units must exactly match the physical size and length of the old unit. The units with the different calibration fit the opening and look the same but were slightly shorter.

For the '57, I believe all of the "right" new-old replacement stock boxes have been labeled TS 18.

Jim K
Detroit
Top of the page Bottom of the page
345 DeSoto
Posted 2010-02-24 9:15 AM (#211444 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Expert

Posts: 1302
1000100100100
Location: Skaneateles,NY(summer)/Port St.Lucie,FL(winter)
Once the connection fitting on the sender starts moving, you might as well buy a new one. They're suppose to be sealed and weatherproof. If they're not, they will eventually start to corrode on the inside of the unit, and fail...
Top of the page Bottom of the page
sermey
Posted 2010-02-24 10:55 AM (#211455 - in reply to #211444)
Subject: Re: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND

345 DeSoto:  They're suppose to be sealed and weatherproof. If they're not, they will eventually start to corrode on the inside of the unit, and fail...

You are right: When putting in hot water, air bubbles went out at the pin. But this in not a problem, because at first running engine this water inside visibly evaporated. Then I was even thinking to add next time a corrosion protection in the test water. But for now I let it so, not finding a replacement.

Top of the page Bottom of the page
sermey
Posted 2010-02-24 11:18 AM (#211459 - in reply to #211170)
Subject: RE: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND

The Constant Voltage Regulator can easily be replaced. See in thread "Make-up your Car":

http://www.forwardlook.net/forums/forums/thread-view.asp?tid=23691&start=101&posts=108#M211457



Edited by sermey 2010-02-24 11:24 AM
Top of the page Bottom of the page
sermey
Posted 2010-02-28 11:34 AM (#211918 - in reply to #211170)
Subject: RE: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND

Now I have found and purchased (never know if I will need anyway):

1959 DODGE CUSTOM TEMPERATURE GAUGE SENDER

- USA MADE

- BUTTON TERMINAL

- 1 TERMINAL 1/4-18 THREAD

- @ 100 DEGREES FAHRANHEIT, 125 OHMS NOMINAL, @ 220 DEGREES FAHRENHEIT, 17.1 OHMS NOMINAL

 Shop: A-z11 Auto Parts   (This seller gives full information!)

 



Edited by sermey 2010-02-28 11:57 AM




(Temperature Gauge Sender LL.jpg)



Attachments
----------------
Attachments Temperature Gauge Sender LL.jpg (51KB - 271 downloads)
Top of the page Bottom of the page
sermey
Posted 2010-03-26 6:46 AM (#215835 - in reply to #211918)
Subject: RE: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND
I have installed the new temperature sensor with 17Ohm (hot) instead of 22Ohm as previous. As expected, the reading on the temp gauge was higher: on last mark of the instruments scale (about 90%). When testing at highest running temperature (low idle, electrical fan off, hood closed and parking) the reading stabilized at full instruments reading (100%). When the engine would really go hot, the instrument cannot show anymore. I had to solve this problem, the voltage regulator being ok.

I inserted a resistor in-line (serial) to the sensor, in order to get the last mark (90%) at upper temperature instead of 100%,  the same difference down at standard running temperature from 90% down to 80% reading
(cut the cable, insert the resistor by soldering and put the cable back in the common harness),.

Now, when the temperature will go over the last mark (90%) means, the engine goes hot, and can show up to 100%. The bigger the in-line resistance value, the lower the reading, but as well the instruments sensitivity at higher temperatures will drop, this can be critical. An in-line value of 5.6Ohm gives the same reading as previous sensor (60%), but at 100% reading the engine would boil long before.

The serial  resistance value I added is 3.3 Ohm (0.3W), for 80% reading at standard running temperature.  - SERGE -




Edited by sermey 2010-03-26 7:08 AM
Top of the page Bottom of the page
jsrail
Posted 2010-03-26 11:10 AM (#215859 - in reply to #215835)
Subject: RE: Defective Water Temperatur Sensor



Expert

Posts: 1590
1000500252525
Location: Scottsdale, AZ

Without trying to steal this thread, can someone tell me where and exactly what water temp sensor I need for a '56 Dodge 315 Poly?

Is there a way to test the sending unit by itself to see if it's good or bad?  Or does it have to be hooked up to the gauge in order to test it?  I don't know much about this electrical stuff.  I have a multi-meter, but frankly don't realy know how to use it! lol

Thanks,     Jay



Edited by jsrail 2010-03-26 1:30 PM
Top of the page Bottom of the page
sermey
Posted 2010-03-26 2:03 PM (#215882 - in reply to #215859)
Subject: RE: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND
jsrail - 2010-03-26 5:10 PM

Without trying to steal this thread, can someone tell me where and exactly what water temp sensor I need for a '56 Dodge 315 Poly?

Is there a way to test the sending unit by itself to see if it's good or bad?  Or does it have to be hooked up to the gauge in order to test it?  I don't know much about this electrical stuff.  I have a multi-meter, but frankly don't realy know how to use it! lol

Thanks,     Jay

Jay, connect an Ohm-Meter (Resistor Tester) from the (disconnected) sensor pin to ground and read the value. This is the cold resistor value of the sensor. Then reconnect the sensor to check the temp gauge, and run the car to nominal temp. Re-disconnect the sensor and check again the resistor value. This is the value on warmed up engine. Now you can put a resistor of the same value instead of the sensor, and you will have the same read-out on the gauge. By decreasing this value, the gauge needle goes up, by reducing down respectively. Remember, this only changes the reading of the instrument, not the temperature of the engine!

For your 56 Dodge you need a sensor with the correct resistor value. At warmed-up Engine connect a variable resistor (0 - 250 Ohm) from the wire to ground and find out the value for normal reading. You can as well use various resistors for test. I think, other owner of this car here could give you the needed information.  - SERGE -



Edited by sermey 2010-03-26 2:05 PM
Top of the page Bottom of the page
jsrail
Posted 2010-03-26 2:41 PM (#215886 - in reply to #215882)
Subject: RE: Defective Water Temperatur Sensor



Expert

Posts: 1590
1000500252525
Location: Scottsdale, AZ

Thanks alot Serge.  I think I can do this, but only a cold test now as the engine is out of the car and I'm still geting it put together after the rebuild.  But now I know how to test the sensor!

Jay

Top of the page Bottom of the page
sermey
Posted 2010-03-28 7:32 AM (#216069 - in reply to #215882)
Subject: RE: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND
On special request: You see the cut wire, from the sensor leading to the temp gauge, then the resistor 3.3 OHM (orange-orange-golden-golden = 5%) wrapped around tje two ends, then soldered for improved electrical and mechanical stability. The white isolation tube,  get smaller when heated and fixes the assembling. This, finally put back in the channel to the other wires, and becomes invisible. - SERGE -


Edited by sermey 2010-03-28 12:28 PM




(1 - Inserted Resistor LL .jpg)



(2 - Packed Resistor LL.jpg)



Attachments
----------------
Attachments 1 - Inserted Resistor LL .jpg (81KB - 257 downloads)
Attachments 2 - Packed Resistor LL.jpg (74KB - 271 downloads)
Top of the page Bottom of the page
wizard
Posted 2010-04-13 10:59 AM (#218324 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
Thanks for sharing this interesting information Serge, I have the very same type of problems with my temperature sensor. Mine was nominal 40 ohms hot and 260 ohms cold - just enough to lift the instrument needle, but no correct reading. First I'll try with the original sensor, which is nominal 236 ohms cold and 24 ohms at 90 degrees C....
Top of the page Bottom of the page
wizard
Posted 2010-04-15 3:47 AM (#218660 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
Ok, now I found out the cause of my problem with low gauge reading! I heated up 2 temperature sensors in water with an ohmmeter connected and a thermometer in the water - both gave me a value of 40 ohms at 70 degrees Celcius (158F). The conclusion was easy - my OEM thermostat has given up after 50 years of service! I bought 2 new thermostats, one 82 C (180F) and one 90 C (195F). I mounted the 90 C thermostat first and presto - my temperature gauge needle went up to the correct medium range. Now I must confirm that the 90 C thermostat does not make the engine too hot on cruises.

The temperature sennsor I use (in fact the OEM one) has these values;
Varm engine @ 90 degrees C (195F) - 22 ohms
Ambient engine @ approximately 20 degrees C (68F) - 230 ohms
Cold engine @ approximately 10 degrees C (50F) - .342 k ohms

The ambient and cold values are not so important - only for comparison when troubleshooting - the higher the value, the slower the gauge will reach "normal" temperature.
The warm value is very important - this will show you the actual temperature of the engine (if the sensor is working correctly) but in ohms. You'll need to confirm the reading with the hot water test. This way it's possible to understand and fix the problems.

Thanks again Serge - you're the man
Top of the page Bottom of the page
sermey
Posted 2010-04-17 2:52 PM (#219010 - in reply to #218660)
Subject: Re: Defective Water Temperatur Sensor


Elite Veteran

Posts: 1080
1000252525
Location: SWITZERLAND

wizard - 2010-04-15 9:47 AM Varm engine @ 90 degrees C (195F) - 22 ohms

Exactly what I measured, Sven. Can say "we are in-line"!  - SERGE -

Top of the page Bottom of the page
wizard
Posted 2010-04-17 2:55 PM (#219011 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
We surely are SERGE
Top of the page Bottom of the page
1960DesotoAdventurer
Posted 2010-04-17 11:12 PM (#219056 - in reply to #219011)
Subject: Re: Defective Water Temperatur Sensor



Expert

Posts: 3588
20001000500252525
Location: Plymouth Spaceport
how often do these sensors go bad?
My 1960 DeSoto reads almost all the way to the right at the hottest setting,yet it runs cool.
Shouldn't it always read a little below the middle?



Edited by 1960DesotoAdventurer 2010-04-17 11:13 PM
Top of the page Bottom of the page
wizard
Posted 2010-04-18 3:13 AM (#219069 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
As you see in my post, I remounted the (probably) OEM sensor and that is 50 years old (thermostat gave up after 50 years), so the problem is more to get the proper reading and the proper type of sender. See my specs for the nominal Ohms above and also Serge's specs and link to a seller that supplies this important information. You'll have to define "cool" - how many degrees is that? Then if you look above in this thread, Serge shows in a understandable way how to fix it.
Top of the page Bottom of the page
Ray
Posted 2010-10-17 8:35 PM (#245979 - in reply to #218660)
Subject: Re: Defective Water Temperatur Sensor


Expert

Posts: 1495
1000100100100100252525
Location: Maple Grove, Minnesota

wizard - 2010-04-15 2:47 AM Ok, now I found out the cause of my problem with low gauge reading! I heated up 2 temperature sensors in water with an ohmmeter connected and a thermometer in the water - both gave me a value of 40 ohms at 70 degrees Celcius (158F). The conclusion was easy - my OEM thermostat has given up after 50 years of service! I bought 2 new thermostats, one 82 C (180F) and one 90 C (195F). I mounted the 90 C thermostat first and presto - my temperature gauge needle went up to the correct medium range. Now I must confirm that the 90 C thermostat does not make the engine too hot on cruises. The temperature sennsor I use (in fact the OEM one) has these values; Varm engine @ 90 degrees C (195F) - 22 ohms Ambient engine @ approximately 20 degrees C (68F) - 230 ohms Cold engine @ approximately 10 degrees C (50F) - .342 k ohms The ambient and cold values are not so important - only for comparison when troubleshooting - the higher the value, the slower the gauge will reach "normal" temperature. The warm value is very important - this will show you the actual temperature of the engine (if the sensor is working correctly) but in ohms. You'll need to confirm the reading with the hot water test. This way it's possible to understand and fix the problems. Thanks again Serge - you're the man

 

If I understand what I have read in this thread, I should be able to bring my multimeter into my parts store and check the part that their references recommend.  At room temperature, I should get a reading of approximately 230 Ohms?

 The only caveate would be - if the sensor works in a way that increases resistance with an increase in temperature?

Thanks,

Ray

Top of the page Bottom of the page
59CRL
Posted 2010-10-17 9:26 PM (#245985 - in reply to #245979)
Subject: Re: Defective Water Temperatur Sensor



Expert

Posts: 2679
2000500100252525


If the sensor increased resistance with heat your temp gauge would never move. You can also adjust the gauge on the back to have the needle
set higher or lower when the car is warmed up. My gauge sits at 1/3rd when warmed up and im driving. Sitting at idle the gauge moves to 1/2.
Top of the page Bottom of the page
wizard
Posted 2010-10-17 11:25 PM (#246001 - in reply to #245979)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
Yes Ray that's correct, a reading of approximately 230 ohms at room temperature will give you a good hint that it's the correct sensor.
When the sensor heats up, the ohms will decrease, until reaching approximately 22 ohms @ 90 degrees C (195F). However, the room temperature reading might differ much, so the hot water test is still the only reliable way to check a sensor.
Top of the page Bottom of the page
Ray
Posted 2010-10-18 10:59 PM (#246147 - in reply to #246001)
Subject: Re: Defective Water Temperatur Sensor


Expert

Posts: 1495
1000100100100100252525
Location: Maple Grove, Minnesota

wizard - 2010-10-17 10:25 PM Yes Ray that's correct, a reading of approximately 230 ohms at room temperature will give you a good hint that it's the correct sensor. When the sensor heats up, the ohms will decrease, until reaching approximately 22 ohms @ 90 degrees C (195F). However, the room temperature reading might differ much, so the hot water test is still the only reliable way to check a sensor.

 

Thanks for the reply. My current (no pun intended) sensor tests as if it is an open circuit. The strange thing is that it is a fairly new replacement.

Top of the page Bottom of the page
wizard
Posted 2010-10-19 1:23 AM (#246158 - in reply to #211170)
Subject: Re: Defective Water Temperatur Sensor



Board Moderator & Exner Expert 10K+

Posts: 12245
50005000200010010025
Location: Southern Sweden - Sturkö island
Ray, try to turn the connection stud around with a pair of pliers and check again. It might be bad contact inside the sensor - see exploded view here above in the thread. Be sure not to use thread tape or other anti-leakage gunk - the sensor must have full metal to metal contact to the engine.

Edited by wizard 2010-10-19 1:25 AM
Top of the page Bottom of the page
Jump to page : 1
Now viewing page 1 [50 messages per page]
Jump to forum :
Search this forum
Printer friendly version
E-mail a link to this thread



(Delete all cookies set by this site)