1971 Duster water temp gauge inoperative

[PFDBat2]

I have a 1971 Duster I purchased 2 month ago. The water temp gauge did not work, I have done the following:

• Replaced the sensor (twice)
• Replaced the Circuit board
• Replaced the gauge
• Replaced the voltage reducer (twice)
• Checked continuity From engine to Gauge
• Grounded the sensor not install, heated with lighter gauge worked
• Installed ground wire from bolt on intake to master cylinder
• Wrapped the sensor (installed) with wire to negative post on battery
• Water comes out or the hole the sensor replaced

Water temp gage still doesn’t Work.

Any ideas

 

[ACME SS]

What are you using for a thread sealant? Only thing I can think is it is not getting a ground through the threads. I usually use teflon tape but I have also used paste type sealant and never had a problem either way. Quite baffling.

 

[Oldmanmopar]

Ground the wire going to the gauge with a ground wire from the battery while someone watches the gauge while the key is on. If it moves you have an engine ground issue. If it doesn't you could have a broken wire or a bulk head issue

 

[Dana67Dart]

Grounded the sensor not install, heated with lighter gauge worked

This one has me confused.

You say the gauge does not work but here you say the gauge worked.


Master tech videos are great

 

[cudamark]

If the gauge works with the sender out, grounded, and hot, I can only think that the sender isn't ground properly when installed, or, your coolant is not getting hot enough to move the gauge.

 

[Dana67Dart]

Is engine block grounded?

If there is restance from the sender to the gauge in the 100 ohm range there will be no needle movement.

Our guages need 10 to 70 ohms ( give or take) to work. Over 70 the needle sits at low no needle movement.

 

[Demonic]

What is the voltage reading at the sensor wire on your DC volt meter?

 

[PFDBat2]

Replaced the sensor (4th one). Now works fine.