I've had false high RPM indications that were the result of a loose ground
wire. Check the wires at the connections to the indicator first - it's
probably easier to get to.

"Don" wrote in message
om...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks