Did you use a sealant on the threads when you installed it? I know, it’s a shot in the dark.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

No. The Sender needs to provide good Ground as the gauge works off varying Ground as the Coolant heats up. Am I wrong?

  

No, you’re right. But I’ve seen Teflon tape used which results is a poor ground. I use aluminum based anti seize (especially in aluminum heads or intakes). What I use does provide a ground. Just figured it was worth asking since yours sounds intermittent. Last resort, might run a ground jumper from the head or the sender body to the battery. And I assume you’ve checked all the other wire connections.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

I could see where tape might be problematic, but wouldn’t ordinary pipe dope merely seal the space between male & female threads, which would have to make a good metal-to-metal ground contact when the sending unit was tightened?

6 VOLTS/POS. GRD. NW INDIANA

I have used Pipe Tape in the past and Unit worked fine. I am forgoing Tape this Time to make sure it was not part of the reason Unit was not working properly. I am going to try the other Gauge I have and see if that fixes it.

  

Daniel, I agree, dope should work. But in aluminum I don’t apply the force I would on iron pipe.

Mark, it was a shot in the dark, just to be sure.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

____________________________