Tachometer acting up

[acuteangler]

I have a Yamaha 115 4-stroke outboard that I have on a 19ft bowrider. I love the motor it is quiet, good on gas and has been very dependable. Recently the tachometer on my boat is jumping all over. If I accelerate to 3200rpm the needle will go to 3200 then start bouncing between 1900 and 4000rpm. The motor is maintaining a steady rpm and is running fine, it is just the tach that is haywire. Can anyone shed a light as to what might be provoking this malfunction. I wonder if it might be a loose connection as the rougher the water the more the bounce of the needle. Where should I look? please help if you can.

AA

[lifeisfun]

Check the selector switch on the back of the tacho.
The Teleflex design isn't the greatest and contacts do get covered by oxide.
Try to rotate the switch couple times back and forth.

[(Big Bass Daddy)]

I have a Procraft with a 135 HP that's been doing the same thing for a while now. The engine doen't over rev, the needle just bounces all over the place.

I noticed that when I turn my steering wheel while driving the needle comes back up and then all of sudden it just drops to zero, but no over reving.

I had a Teleflex system before and now I have a Rack system, is this something that can be fixed by a simple cleaning job of the connections at the tachometer or should it be brought in and have it serviced? What's your opinion?

Sorry for jumping on your tread.

BBD

[lifeisfun]

Nothing to do with the steering system.
The Teleflex tacho needs to have the selector switch cleaned.
Hold your finger and apply light pressure over the black rotary switch ( on the back of the tacho) and it should fix the problem.