Gauge wiring problem (electric water)

As usual, I'm a little confused. The gauge should use resistance in the sending unit wire to register a reading on the guage. For instance, if you ground the wire that's on top of the sending unit, the gauge should peg at max.

The sending unit body does need to be well grounded (usually achieved via the motor and its threads) so your idea to ground the sender body was a good one. I have run dedicated ground wires from the sender housing to ground - just being sure that the wire gets no where neat where the actual sending unit wire wire attaches (or the gauge pegs).

For the issue, if all wiring looks good, and your sending unit wire ohms out with no resistance when disconnected (to make sure the wire didnt chafe and partially short during installation), I have one thought:

I recall from some time back, a guy said he got a gauge with a sending unit for another guage (as you know, they sell elec gauges with different scales) - basically the sending unit and gauge were not calibrated for eachother. He got the right sender and it was good-to-go. I know you got a second sending unit, but it's something to file away if all else fails.

I really dont have any great ideas though brah.

Good luck and bump.

281pony said:

ill post a pic, however. if i run a ground off the sending unit body, how would i attach such a wire/make a ground?

the issue must lie in my grounding then, since it seems to have done the proper thing when i connected the ground wrong.

Click to expand...

I'm not sure that the ground on the sender will help. If you were reading way too cool, then I'd jump on that. But if the sender is capable of creating such a hot reading, that suggests it's grounded decently (you can ohm out the sender body if you want - it takes 10 seconds).

I have put a sender in a tee in rubber lines before (no ground at all) and soldering your own ground-wire to the sender body would work. If you want to do it for testing, bare the wire and zip tie it to the body or use an aligator clip. I am not conversant with the looks of your cooling system (a Degas set-up probably) so I really dont know about air pocket issues or the grounding issue - this is just my theoretical two cents.

I mainly just wanted to post about the grounding of the sender body probably not being a solution (it takes 2 mins to make a ground wire for testing though if you want to play with it). I'll have to let it simmer and see if something else comes to me.

Good luck!