My temp gauge has gone crazy in my 63 SWC. After running for a short time the gauge works fine and then it goes to the hot side and peggs out and will stay there but will move now and then when I hit a small bump. When I shut the car off and let it cool over night and go to start it up the next day it is still pegged to the hot side and after about 2 min. it will start working and then it starts all over again. Anyone have any ideas on this crazy trouble or what I need to do to fix it. The car is not running hot, just the guage is running crazy.

 

I'd guess that you sender is "busted".

If you ground the wire to the sender to the block, the gauge will peg.

SO...if the "variable" thermo-gizmo within the sender is broken, or more likely, the bakelite insulation around it, the wire grounds directly, and the gauge pegs.

Could also be that the wire to the sender is intermittantly grounding too.

I'm NO electrical engineer, BUT, I'd check the sender first, then the wire to the sender.

Chuck

 

Chuck I just put a NEW sending unit on the car and it still is doing it. Any more ideas?

 

The wire to the sender.

Could it be grounding somewhere along its' path to the sender?

Chuck

 

I will check it out and let you know. Thanks Chuck

 

Mike,

If you used teflon tape on the sender threads, that may be causing the problem.

 

My temp gauge was loose in the cluster causing a poor ground on my 63. (It would start out mid-range and then peg way hot when warm)I reached under and pulled the gauge tight and it worked perfect. Had to remove the cluster to tighten the 1/4 inch nuts that hold it in place. If you need a nos 63 temp gauge (per paragon ) turned out to be (used in bag) let me know. It works, didn't have a need to put it in though.

 

If you disconnect the wire at the sender, the gauge should peg to the cold side; then if you ground the terminal to the engine, the gauge should peg to the hot side. That eliminates the sender as a contributor to the problem, and verifies the gauge function. If you have the wire disconnected at the sender and the gauge pegs to the hot side, the sender wire is shorted to ground somewhere between the sender terminal and the gauge.

 

Thanks JohnZ I will check that out.