Erratic Tach

[Snipe]

The 50HP Mariner mounted on a pontoon has an erratic reading on the tach. It runs steady and smooth, no miss or carb malfunction, but as we cruise (1800-2000 rpms) every once in a while the needle will jump close to the top. Then it will be alright for a while and jump up again never missing a beat. It's been like that for a couple of years now, no other problems.

 

[Trent]

Re: Erratic Tach

Charging the battery ok? Tach is electrically connected to the charging circuit. Eratic tach is the first indication of charging system problems.

 

[Snipe]

Re: Erratic Tach

Thanks for the input.........<br />The batt. meter does show charging @ about 16 amps. If I turn the running lights on it will go down to just over 14. That's running at over half throttle.