Weird gauge problem

[dggrant]

Hi Guys:

I took Annie out of storage and thought that it was a good time to re varnish the dash  🙂

I took off the dash being careful to label all the wires to the gauges so I can put it all back together correctly.

I think I have done this but……

Speedo, Amps, Gas – all working correctly

Oil Temp never worked so nothing new there

The problem is with both the Tach and the Oil Pressure. Both seem to be “stuck” at the top end of their readings. This would be 5 o clock for the tach and about 2 o clock for the oil pressure. The needles on both move a little when ignition is turned on and seem to “tremble” when car is running.

I have disconnected and reconnected the battery (no change). The gauges are “Vintage Reproduction” models.

Any ideas as to what is going on or how to get them reading correctly?

Thx

[Toller]

Dan
I encountered identical problems with oil pressure and temperature gauges. If you disconnect the + and sender (aka -)wire from the gauges then connect with jumpers to + and – of battery the internals of the gauges should reset the needle back to zero (at least it did so on vintage VDO gauges). Reconnect the proper wires then see if problem is corrected. Second possible issue could be with the sender. It has a variable resistor within the unit that controls the electrical flow to the gauge. If you have volt/ohm meter you can check if the sender is working as designed. One probe is connected to + and other is connected to tab on sender. Make sure you have VOM set for reading DC voltage. If you get 12+ volts with a cold engine the sender is defective and will have to be replaced. If you touch the negative probe to engine and get same reading as sender then sender is probably defective. As for tach, you can try some procedure but as I never had a problem with tach can not guarantee that problem will be rectified

David B Dixon
Port Perry ON CA
Sabine

[Toller]

For temperature gauge I replaced the original VDO black face gauge with a white face Royale model, thinking the original gauge was defective. I was getting the needle on the gauge barely moving off of 150 deg after a good run. I tested the temperature sender with boiling water and got the same reading. The stamp on the sender showed 150 F so I concluded gauge was not rated for 180-220 operating temperature of engine and ordered a 300 deg sender. Hopefully it will correct problem when I receive it from CIP1

David B Dixon
Port Perry ON CA
Sabine

[dggrant]

Hi David:

Thx for the reply.

I’m assuming that the gauges work (except the temp) as the did before I removed the dash. I will give this a shot.

I was hoping not to have to remove the dash again but it is probably easier that way

[Author]

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