Electric Tachometer

[Jim Rainer]

I've just been through this problem on both tachs and discovered that 9 times out of 10, the problem is in the mags or wiring - not the tach unit itself. I did find a place in Arkansas that will overhaul the tach unit for a resonable fee but didn't need it. My 337 is a G model so yours may have a different mag system.

Start in the mags first and work forward (or backward as the case may be) is my suggestion - assuming your system is similar to the G model.