Not sure if this is the place but i thought i would ask. I have a 1955 olds 88 that i just put in a new temp sending unit and my gage is pegging hot. Is there a way to trouble shoot to figure out whats not working (gage, sender or wired wrong).

Thanks in advance, mike

 

Does it peg to hot when the car is cool and you turn the key on? Have you tried disconnecting the sending unit and see what it does? What did it do with the old sending unit?

 

I went out and turned the key the gage needle moved to the first mark and stayed put. I started the car and in 5 minutes the needle was pegged and yet the motor was not so hot that the thermostat did not open and you could touch the heads with your hand. When I disconnected the wire the gage went all the way down to the cool side. I'm in the process of trying to get back my original sensor. I sold the motor and trans. The sensor I just put in is a TS 6

 

It sounds like the sending unit is the problem.

 

The 1955 Olds shop manual shows a procedure on pages 13-37 and 13-38 to test the temperature gauge using a tester for the temperature and fuel gauges. I agree that it is likely the sender at fault, especially if it worked previously. I'd try to get the old sender back and use it.

 

I want to thank you guys for your advise. I was able to get the original sending unit from the original 1955 rocket motor. The water temp gage now works like new.

Again thanks for your help, Mike