Tachometer / engine problems?

[Searayking]

I have noticed recently that my tach had been acting weird (I.e. reading 0 rpm at low speed, then correcting at higher speed). Yesterday, I took it out and while pulling into dock, the engine stalled. I was able to restart and park. I had dinner and then restarted the boat to head home. The tach read 0 rpm regardless of engine speed, then the LCD started beeping and read "check engine". All other engine diagnostics seemed ok. I was able to make it home, but wonder if it is a bad connection, bad tach, or something else. How easy is it to remove the tach?

 

[moparlvr4406]

possibly a crank position sensor
scan it and see what the code is ??

 

[Xplicitlnck]

Read this http://clubsearay.com/showthread.php/48748-Erratic-Tack-s

 

[David C]

Dirty, corroded connections are common cause. On back of many tachometers, there is a switch to allow installer to select the number of cylinders of the engine. The contacts on this switch can get corroded also, and many times just moving the selector back and forth a few tiomes will clean the connection enough for several years dependable use before it acts up again.
Bottom line, check/clean all at the tachometer connections first and you will likely fix your problem. I seriously doubt that the tachometer is actually failing. The connection at the engine can also get corroded but much less likely.