Mercury Tachometer Question

[final_fantasy]

Hi All:

My '97 2-stroke Mercury Outboard 135hp (NOT an optimax) has a little issue with the tachometer. It seems to "flutter", like the needle sways all over the place for a minute or two, then will eventually give a normal reading.

For example, If I'm running at headway speed, the tach needle will hover between 2-3k rpm, which I clearly am not at.

Engine seems to run fine otherwise, no other problems (knock on wood)...

What are some things I should look at in troubleshooting this problem?

Thanks in advance.

[Roccus]

Check for lose or corroded connections on both the tach and the rectifier( the gray wire is the sigmnal wire)... if all is well, replace the tach, it's driven off of voltage spikes from the stator, a bad rectifier can make the tach inoperable, but when the rectifier goes bad, it either works or it doesnt....

[final_fantasy]

Originally Posted by Roccus

Check for lose or corroded connections on both the tach and the rectifier( the gray wire is the sigmnal wire)... if all is well, replace the tach, it's driven off of voltage spikes from the stator, a bad rectifier can make the tach inoperable, but when the rectifier goes bad, it either works or it doesnt....

What are some other symptoms of a rectifier going bad, other than my tach issue?

I did have an isolated problem one day where the engine would NOT turn over after it stalled in an idle. I probably cranked it 15 times before it finally did turn....

[Roccus]

If the rectifier is bad, the engine wont charge the battery... if the battery doesnt charge ... you know the rest...

[final_fantasy]

Thanks Roccus. If you ever need help fixing your computer, let me know, I'm a technician in the IT field :)