Re: Tach Issues
I am guessing that you mean you have 12vdc power going to the tach gauge from the ignition switch. While that is a good thing too, you also need to confirm that you have power in the "send" wire coming from the motor. The "send" wire carries the tach signal to the gauge. If this wire is dead, your gauge will not respond to engine RPMs.
The previously mentioned Teleflex troubleshooting guide explains how to test for proper power/signal in the "send" wire. It should be something like 5-7vac at 2000 RPMs. If you confirm that the "send" wire at the gauge end is dead, you can then trace it back to see if the voltage regulator is at fault or if you just have a bad connection somewhere in the wiring between the tach gauge and the regulator. If you determine that the voltage regulator is at fault, try switching the "send" wire to the other voltage regulator on the motor. Although only one voltage regulator is connected to the tach gauge, either voltage regulator can be used.
Good luck...
