Tach issues on a 2000 Volvo Penta

[CascoBay]

I have a 2000 Volvo Penta 5.7L GS engine, and the tachometer is erratic when I operate items such as the outdrive tilt/trim. If I drive a long distance at idle it often will read 3K RPMS when it should be around 1K. If I bump the engine speed up a bit the tach drops down and reads correctly.

Is there a common fix for this or something I should be looking at?

 

[Don S]

Re: Tach issues on a 2000 Volvo Penta

Loose or corroded connection some where. Probably a ground.

 

[CascoBay]

Re: Tach issues on a 2000 Volvo Penta

Where does the tach signal come from? The coil?

 

[2003lsr]

Re: Tach issues on a 2000 Volvo Penta

http://faria-instruments.com/site_manuals/IS0100_Tachometers.pdf

Have a look at the above link regarding Faria Tachometer troubleshooting. Page 2, Para D in regards to high readings.

 

[fossill]

Re: Tach issues on a 2000 Volvo Penta

Just replaced my Faria tach on warranty. Same issue as yours. If they get overtightened on the mounting clamps (wrecks the internals) they also act up like that.

 

[CascoBay]

Re: Tach issues on a 2000 Volvo Penta

Thanks guys, I will take a look!