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| | | | Joined: Mar 2020 Posts: 4 New Guy | | New Guy Joined: Mar 2020 Posts: 4 | Hello everyone
I have a 55 Stepside with 235 engine which had a damaged capillary type temp gauge ,I replaced it with an electric gauge from a 56 .I also drilled out the lower thermostat housing and taped it with a 1/2 pipe tap to install sending unit,and plugged the old hole in head.
I bought a new stock sending unit for an electric 56 gauge from Bills truck shop and installed it in truck and no matter how long you run the motor the gauge does not move and I have cleaned the gauge cluster grounds and the motor ground.
If I ground the censor wire the needle pins and I get the same result bench testing , as for the censor being one for a idiot light I checked it with an ohm metre and it showed different readings when heated.
I have read through all the old treads on this same problem and it appears I need an original 50s electric sending unit from this truck or an aftermarket –-NTC –-calibrated sending unit as was the original.Has anyone found an after market sending unit that works even if its not that accurate ?in the ball park would be good.
Moe
| | | | | Joined: Feb 2004 Posts: 29,792 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,792 | Is your electrical system 6V or 12V? If you're running a 6V system there is no Chevy sending unit that I'm aware of that will have the right resistance. Try one calibrated for a pre-1955 MOPAR or Ford cooling system with a 6V electric system.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Mar 2020 Posts: 4 New Guy | | New Guy Joined: Mar 2020 Posts: 4 | Well after another day of testing using a gas gauge sending unit as a sender in and out of the truck, double checking everything .I now have it working ,when I checked the ground for the gauge cluster I used a test light and touched the end of the ground wire.This was still attached to cluster and yes I had a good ground,this was with the whole instrument cluster just hanging out on column.Turns out the ground wire itself was not connected, I guess I-was getting a ground from the oil capillary tube.Well a poor ground and having the sender and ignition wires mixed it caused me a lot problems.One thing I did learn is that if you don’t have your stock 56/59 electric gauge grounded at the cluster it will cause a pinned needle reading and other false readings.So like Someone said on the old treads CHECK your grounds and I say check them them again and prove your readings 😂.thank you all o
Moe
| | | | | Joined: Dec 2002 Posts: 3,441 Moderator - The Electrical Bay | | Moderator - The Electrical Bay Joined: Dec 2002 Posts: 3,441 | Rusty Rod always recommends checking your grounds! good work finding the issue.
Another quality post.
Real Trucks Rattle
HELP! The Paranoids are after me!
| | | | | Joined: Mar 2020 Posts: 4 New Guy | | New Guy Joined: Mar 2020 Posts: 4 |
Moe
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