Tach Question

[Lance Jones]

I have a problem with my tach. When I first start the motor, it registers (most of the time) idle speed. However, when I increase power, the tach stays at idle or slowly moves up. Then, suddenly, it returns to normal function bot at power addition or taking power off. Could this be a tach cable problem?

[Gary]

I  had a similar problem in our original tachometer (a986) and it traced to an intermittent electrical connection in the tach light. It was loose in its mechanical connection in the socket. Cleaning and making sure the light is very tight in the socket solved the problem. I think the current fluctuation may have caused the tach to read differently based on vibration.

Good luck.

Gary

[Stu Jackson]

...or a seriously slipping belt.

[Tom Soko]

I'd check every electrical connection between the engine and the tach.  Also, a call to Seaward told me to rapidly move the ABCDE selector on the back of the tach back and forth, to eliminate any possible corrosion that might have built up on those contacts.  Moving the selector cured my erratic tach. Hope this helps.