Gauges and Dash lights Help

[rcadick]

Hoping someone can help me with what I hope is a simple fix, but have my doubts.

I have a 1964 Polara 440 with a 225 slant six. The engine was rebuilt four or five years ago and I've put about 2000 miles on the car since. When rebuilt an electronic ignition system (the kind that hides in the distributor) was installed.

Over the past year or so I've had a problem that has progressed and I will try and detail it as simply as possible.

1. The first problem was my temp gauge began fluctuating wildly swinging from hot to cold and occasionally stabilizing at a temp that was not possible given engine run time. I noticed this problem when headlights were off.
2. I then noticed that when I turned my headlights on the temp gauge would swing to the opposite side of the dial, hot to cold and vice versa. But my fuel gauge also started moving at this time as well.
3. This began to get progressively worse with the fuel gauge moving at a more rapid pace. (I should add that when the engine was rebuilt a new fuel level sending unit was installed in the new fuel tank).
4. Fast forward to today and neither my fuel gauge or temp gauge appear to work at all both pegged to the left (cold and empty respectively) only moving a millimeter or so when I turn on the headlights.
5. When My headlights are on, occasionally I lose all dash lights and my turn signal indicators (sometimes both, sometimes one) light up continuously.

So...help? lol.

Of note: At one point the engine did get hot enough to cause coolant to spray out of the heater valve. The problem did seem to get worse after this. I have since pulled the heater box and replaced the gaskets int he heater valve with no problems since.

I have also tried checking the two white ground wires for the headlights on the radiator brackets, cleaning and reattaching them but it had no effect, apparently.

I have also replaced the instrument cluster voltage regulator, with the only noticeable affect being the oil pressure gauge started indicating a slightly lower oil pressure than with the old voltage regulator.

Thanks for any insight or tips anyone can give.

 

[Longknife]

Ground!!!!

 

[rcadick]

Ground!!!!

Other than the ground for the headlights (by the radiator drivers side, where is another ground located?

Thank you!

 

[Longknife]

I believe the ground circuit wires are black. I am not familiar with those earlier B bodies, do you have a service manual?

manual

 

[Durandal25]

I have a handful of tips, but as a rule....assess very carefully.....the condition of the dash harness.....then review the wiring diagram for your grounds. I had a lot of gremlins on the 67 Coronet ....and all were resolved via grounding and circuit testing. the pegging gauges are a sure sign that something jenky is up with the ground.

 

[rcadick]

I believe the ground circuit wires are black. I am not familiar with those earlier B bodies, do you have a service manual?

manual

I do not, sadly. So far, the only grounds I've found are white, but, that's only two so I'll keep looking.

Thank you!

 

[Longknife]

The picture below is, I think, the two circuit boards you have. The ground for this type of circuit board is accomplished by the screws that hold the circuit board to the metal gauge housing and the housing then grounds by screwing it into the metal dash frame. follow the circuit and note the three hold down screws in each board that pass through the circuit. Run a jumper wire to any one of these screws to ground a ground,,,