Generator light/general gauge issues
#1
Racer
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Thread Starter
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Just trying to figure out if I should replace gauges/cluster al together, or go "piece by piece.
Just bought a '77 earlier this week.
Gen. light comes on intermittently--ie, I started the car in the garage this afternoon, generator light came on, voltage meter did not move form the bottom (no voltage)...
10 minute later, I started it again, and the light was NOT on, and the gauge was reading appropriate voltage.
What gives?
I also noted that the fuel gauge tends to "float" a bit while driving.
The temp gauge is inoperable--I even grounded it out under the hood and not even a twitch of the gauge (I assume grounding it should have pegged it over hot)?
Oil gauge seems to work OK, but is not always "steady"--very slightly moves back and forth at idle...
Thoughts on repairing, or should I replace the whole gauge cluster, circuit, etc?
Clock also does not work...
Just bought a '77 earlier this week.
Gen. light comes on intermittently--ie, I started the car in the garage this afternoon, generator light came on, voltage meter did not move form the bottom (no voltage)...
10 minute later, I started it again, and the light was NOT on, and the gauge was reading appropriate voltage.
What gives?
I also noted that the fuel gauge tends to "float" a bit while driving.
The temp gauge is inoperable--I even grounded it out under the hood and not even a twitch of the gauge (I assume grounding it should have pegged it over hot)?
Oil gauge seems to work OK, but is not always "steady"--very slightly moves back and forth at idle...
Thoughts on repairing, or should I replace the whole gauge cluster, circuit, etc?
Clock also does not work...
#2
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1. Voltage, if it happens again put a voltage meter on the alternator and see if it is working.
2. Gas gauge, there will be some movement such as going around turns, up or down steep road surfaces, etc. Depends on how much float you are getting when on level ground going straight. You could check the ground connection on the frame for tightness and lack of corrosion.
3. Temperature, trace the wire to make sure there is no break before blaming the gauge.
4. Oil pressure, have you changed the oil and filter?
2. Gas gauge, there will be some movement such as going around turns, up or down steep road surfaces, etc. Depends on how much float you are getting when on level ground going straight. You could check the ground connection on the frame for tightness and lack of corrosion.
3. Temperature, trace the wire to make sure there is no break before blaming the gauge.
4. Oil pressure, have you changed the oil and filter?
#3
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Oil gage fluctuation is normal within a few lbs. Taking out the cluster is not easy the first time but not that hard. You must remove the entire assembly. If it has been removed before it very possibly can be the printed circuit on the back of the cluster. It is a flexible circuit and where the connector from the car attaches is VERY easily damaged when reinstalled. With the cluster out it is very easy to troubleshoot all the gages. For the clock if it is getting power and has a good ground ( you can test with a batt. charger) look at rear of clock, you will see a piece of tape covering a hole. Remove tape and spray a small amount of WD-40 in it. Rotate the clock around and then retry putting power to it. Changing the gages is easy as is troubleshooting the circuit board. Just need a VOM.