[timbergrove]

Need some advise, please. I have completed a restoration on my 65 gto. Most everything is fine except the tach does not work now. I don't know if I broke it during the resto or if it is just not compatible with the new Pertronix Ignitor electronic ignition and coil that I installed. I checked the wiring. I eliminated the resistance wire to the coil per Pertronix manual. I hope that did not destroy the tach. The needle is stuck around 1000 rpm all the time and does not move when the engine runs. The needle bounces a little if I tap the tach. The tach case is at ground potential and the lead checks out to the coil.

Before I replace it, is there a test I can do to prove it is bad? Replacing it is a mean job for a big guy like me. I'd hate to put in another one only to find it was not the problem. Any advise or in-car tests would be appreciated.

Thanks.

Bob

There are 10 kinds of people, those who understand binary and those who don't.

[timbergrove]

Need some advise, please. I have completed a restoration on my 65 gto. Most everything is fine except the tach does not work now. I don't know if I broke it during the resto or if it is just not compatible with the new Pertronix Ignitor electronic ignition and coil that I installed. I checked the wiring. I eliminated the resistance wire to the coil per Pertronix manual. I hope that did not destroy the tach. The needle is stuck around 1000 rpm all the time and does not move when the engine runs. The needle bounces a little if I tap the tach. The tach case is at ground potential and the lead checks out to the coil.

Before I replace it, is there a test I can do to prove it is bad? Replacing it is a mean job for a big guy like me. I'd hate to put in another one only to find it was not the problem. Any advise or in-car tests would be appreciated.

Thanks.

Bob

There are 10 kinds of people, those who understand binary and those who don't.

[george kujanski]

Sounds like a mechanical problem; not electrical. Somehow the internal movement is stuck. I've seen one where a critter built a home in there jamming the movement.

Regards, George

[Peter Serio]

I agree, there has to be some sort of blockage in the meter movement, this is a VERY common probelm with tachs that were originally designed to last 10 or 15 years MAX!
I think maybe either rust, paint chips or lint/dirt has gotten it there jambing up the pointer's float, or the return spring has broken &/or fallen off. . That said, the modern elctronic conversion kits 9 times out of 10 the old tachs will NOT operate off of the conversion, you have to have the tach totally rebuilt to transistor ignition standards.


Peter Serio
Owner, Precision Pontiac