Amp Gauge Fluctuation at Idle

[James W.]

The amp gauge at idle fluctuates really fast, actually looks like it is vibrating of bouncing from the middle or top center of the gauge to the positive side of the gauge, only moves about 1/8 of an inch.

Anyone have any advice as to what the cause is and what need to be checked? This is happening after a complete restoration of the car. The alternator and voltage regulator were rebuilt by John Pirckle. The car is a 1965 Corvette equipped with a 396 engine and TI ignition.

Any help would be greatly appreciated.


Thanks,

James West

[Domenic T.]

Re: Amp Gauge Fluctuation at Idle

James,
I would call the rebuilder of the alt & regulator as he is a expert in this area. You may be seeing the regulator points working when you look at the amp gauge.

DOM

[Domenic T.]

Re: Amp Gauge Fluctuation at Idle

James,
Forgot to mention that I removed my cluster and forgot the ground way back in 1971 and had that problem followed by the amp gauge internal winding burning the a wire (1or2 turns).

DOM

[Edward J.]

Re: Amp Gauge Fluctuation at Idle

The amp gauge at idle fluctuates really fast, actually looks like it is vibrating of bouncing from the middle or top center of the gauge to the positive side of the gauge, only moves about 1/8 of an inch. Anyone have any advice as to what the cause is and what need to be checked? This is happening after a complete restoration of the car. The alternator and voltage regulator were rebuilt by John Pirckle. The car is a 1965 Corvette equipped with a 396 engine and TI ignition.Any help would be greatly appreciated.Thanks,James West

Jim, Reach your hand behind the gauge while its idling and wiggle connector to see if it helps, maybe a connection issue . another quick test is check the amp. output with a charging system tester and see if the meter on the tester is doing the same thing as your gauge. If you have a local guy that repairs your other cars maybe he can hook up his machine for a test. if all is well with his machine I would head for the gauge.

[Alan D.]

Re: Amp Gauge Fluctuation at Idle

I had the same problem on my 1977. Sent the alternator back to Pirkle and it checked good.
I cleaned all the connections to the alternator and made sure there was a good ground. I found paint on the mounting bracket and cleaned and the problem went away.
Al Dieterle

[Joe R.]

Re: Amp Gauge Fluctuation at Idle

James,

Sounds like you just have an amp gauge that has lost the dampening fluid. The pointer has two things to keep it at "0" in the top center. First it has a small magnet and then the small wheel is in some kind of dampening fluid. Probably silicone. After years the dampening fluid leaks out or evaproates. Then you have a pointer that is very sensitive to motion, especially with a BB rumbling under the hood. It should have been replaced when the cluster was rebuilt but it could have happened since that time. Buy a new one and go on down the road.

JR