Tach problems

[mmarzella]

99 Johnson 90 horse, just installed new Optical sensor, timing cover and power pack. Took it on the water for a test ride and ran great except the tach shows 0-500 as I idle then drops back down to 0 when I get up on plane. Also I see the tach increase a little when I trim the motor up while at idle. Any thoughts on why this is happening? Thanks

 

[boobie]

Re: Tach problems

Could have a prob with your tach or reg/rectifier. Put a volt meter across your battery and run it. If the voltage comes up to around 14.2 the charging system should be okay which your tach runs off of. Then look at the tach.

 

[Chris1956]

Re: Tach problems

Don't forget the wiring between the tach and the stator. When I bought my '98 Johnny 150HPV6, it came with some melted wires. These included the grey tach sender wire.