Bad tach??

[marcengillb]

I have a 90hp merc (1995)my tach never stays in one place It varys 7 or 8 hundred rpms all the time up and down.It doesent move at idle.Starts moving at about 1500.Full throtle stays around 5000 but touch the trim it goes backward.Any ideas,bad tach??

 

[andy6374]

Re: Bad tach??

Could be...First, have you checked to see that all the connections are tight and free of corrosion. Connections at the rectifier where the tach signal is received from the stator charging coils and the connections at the tachometer itself. <br /><br />What kind of tach is it (quicksilver, faria...).

 

[marcengillb]

Re: Bad tach??

Thanks for the reply.Its a quicksilver tach and I have checked connections on the tach but dont know where to check on the motor.

 

[andy6374]

Re: Bad tach??

Look at the strb. side of the engine. Find the starting solenoid, trace the positive red lead that goes to the rectifier (small square shaped object with three posts on it). The other two posts on the rectifier are for the two yellow stator charging coils and on of those posts there should be a gray wire. The grey wire is your tachometer signal. Make sure all this connections are tight.<br /><br />Is your battery charging?

 

[marcengillb]

Re: Bad tach??

Thanks for the help,My battery must be charging because I have been fishing about 5 times in the last 2 weeks every time I check it it is fully charged,Im going to look at those wires today,I will let you know.