1988 merc 150 tach

[philipjames5k5]

This is the last thing I need to do to get my boat tip top. All my gauges work besides my Tach. Can anyone give me a troubleshoot guide on fixing this. I tried the search but didnt really see anything.

 

[Chris1956]

Re: 1988 merc 150 tach

Tach usually zero when power is applied and the motor is not running. The tach runs off the AC signal from the stator, plus +12VDC and ground. A bad voltage regulator or rectifier can cause the tach to not read anything or read wrong. The wiring between stator can go bad.

You need to isolate and test these items to determine your issue. Testing with a known good tach is a good way to start.