235 temp sending unit

1957 235, 3200 trk, replaced original with a new one and the gauge ran hot even though the temp was ok. Replaced with another from a 1960 235 trk and gauge runs cold even though temp ok.Have also replaced gauge with NOS with no change. Any suggestions to get it correct?

 

You aren't using sealer (teflon tape, etc.) on the threads of the sending unit, are you?

 

No, what does that do? Thanks for getting back to me.

 

It could electrically insulate the sending unit from ground, causing an incorrect reading. But if you aren't using teflon tape, that shouldn't be your problem.

 

Electric Gauge Testing

I wonder if the dash pod is poorly grounded , or maybe the engine to body ground strap is gone missing ? .

That'll do it as will having the wrong sender .

Here's how to test the gauge head : key on , disconnect the sender wire at the sender & ground it ~ the gauge should peg . wire disconnected , the gauge should peg in the other direction .

If so , the sender is Kaputi or wrong . if it doesn't respond to grounding or open wire , there's prolly a poor ground in the dash some where .

Fiddly and a slight PIA to diagnose but keep at it and you'll get there .

Last ditch ? use the mechanical one with Bourden Tube from a '55 .

 

sending unit

Thanks for your input. It is greatly appreciated.It may be some time B4 I get to it but will follow up then.

 

Wonky Gauges

No worries , no hurries , we'll be here .

 

I replaced mine and it worked fine. But every once in a while the gauge will got to hot or cold. So II just smack the gauge and it gose back to working. So im gonna go with your gauge needing repaired as well.