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Surfpilot
08-09-2014, 02:53 PM
All of a sudden, all four of my dash gauges appear to be misreading. Fuel gauge reads half tank low, engine temp is cold at operating temp, oil pressure reads higher than normal, and ammeter shows discharge. This happened all of a sudden a few days ago...any ideas how this might occur and what I can do to correct it? Stumped.

GinettaG12P
08-09-2014, 02:58 PM
Don't know what year your car is, but in the 50s, cars had a "voltage stabilizer" that reduced the voltage to a value below full battery voltage. This allowed the instruments to see a constant voltage regardless of battery condition (unless lower than the "stabilized" voltage.) If the "voltage stabilizer" fails - some of them were mechanical with bimetal heating coils - the gauges get wacky. That could be your problem.

Surfpilot
08-09-2014, 03:05 PM
It's a 63 lark. Don't believe there is a voltage stabilizer

Flashback
08-09-2014, 03:09 PM
Check your charging system FIRST or for a short. Then ground

Surfpilot
08-09-2014, 04:38 PM
Tested the alternator. It's good. While I was there in there I noticed some melted wires on the wiring harness. Bingo, that must be the problem. Wires shorted and melted a bit. Here's the question now: is it worth cutting splicing new wire or should I bite the bullet and get a whole new wiring harness?

sals54
08-09-2014, 04:56 PM
Check your charging system FIRST or for a short. Then ground

Ditto… check your grounds. Make sure you're grounded body to frame and frame to engine. Then be sure you've got good contacts to your dash.
And secondly, you didn't say what car this was. If its an Avanti, then double your efforts on searching out your ground issues. And don't bother grounding to the body. Fiberglass is not a very good conductor. JK

reichsrundfunk
08-10-2014, 01:50 PM
All of a sudden, all four of my dash gauges appear to be misreading. Fuel gauge reads half tank low, engine temp is cold at operating temp, oil pressure reads higher than normal, and ammeter shows discharge. This happened all of a sudden a few days ago...any ideas how this might occur and what I can do to correct it? Stumped.

If the ammeter on the instrument board is showing a normal charge rate then your instrument board has a bad ground. Reground the board---especially the cluster area and that ought to take care of the issue. Make sure the area you are grounding to chassis us CLEAN and rust free.

Surfpilot
08-10-2014, 02:07 PM
Ok will try that, however as I noted in post #5, I found melted wires on the wiring harness, so there's my short right? Should I replace the wiring harness?

RadioRoy
08-10-2014, 02:49 PM
Ok will try that, however as I noted in post #5, I found melted wires on the wiring harness, so there's my short right? Should I replace the wiring harness?

If you splice in new wire segments, solder them and cover the joint with heat shrink tubing. Do not use crimp connectors. They develop high resistance and get hot.

Surfpilot
08-16-2014, 12:45 PM
Follow up, in case anyone cares: after some head scratching and some more electrical voodoo going on, I was able to isolate and fix the problem. It was the voltage regulator. It had gone bad and was causing a low voltage situation, so everything from engine starts to gauge indications was wacky. New voltage regulator and a charged battery and we're back to normal. Thanks for the help guys

StudeRich
08-16-2014, 08:33 PM
Very Typical, on Studebakers it is almost ALWAYS the simple easy stuff that will "throw you"! ;)

Overthink it and you will just run into a dead end, if you don't believe me just ask Jim Studebaker. :D