cmac72

Just installed a replacement tachometer board on my 79; tach actually moves when I rev the engine now (redlined at engine off before); however, at idle it rests at zero. Is there another calibration I need to do to get it to read correctly.
Thanks.

zwede

Yes, the needle is not keyed to the shaft, so it can be installed any way you want. You have to push it on showing the correct rpm.

You can get close by powering the tach and then installing the needle to show zero.

cmac72

Thanks very much; I'll try it first thing tomorrow.

zwede

What I found on mine, though, was that power on/engine off wasn't quite zero on the tach, so when I installed the needle that way it read a bit high. If you have a handheld tach you can idle the engine, note the rpm on the handheld and set the needle to duplicate the reading.

cmac72

Thank you, good tip to try if I can't get it read correctly.