New tach not working, what can I check?

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jasindude1
Posts: 10
Joined: Fri Sep 04, 2020 7:15 pm

New tach not working, what can I check?

#1 Post by jasindude1 » Sun Aug 21, 2022 8:47 pm

I bought a new tach on Amazon, set it to the correct setting, wiring is good, ground good the tach does turn on and display the other items, (water and outside temp) so the gauge does work but no RPM signal, my purple/grey wire is connected all new wiring and connectors. I have a 88 Merc 60hp outboard with a pre-94 force wiring, so purple is the tach. How can I verify the grey wire is sending a signal? I have my voltmeter with me at the lake, what reading should I get from the grey wire to the tach? Also was reading could be my rectifier? The engine is charging my starting battery when running, I am able to see the voltage while the engine is running, but what reading should I get on the rectifier? Or at the grey wire on the rectifier? Any help would be appreciated im at the lake for another few days so would like to get this ironed out if possible.

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Rick McC.
Posts: 417
Joined: Fri Mar 31, 2017 7:12 pm
Location: Weeki Wachee, Fl

Re: New tach not working, what can I check?

#2 Post by Rick McC. » Sat Sep 17, 2022 7:04 pm

Well, if you grounded a hot wire at anytime during your tach installation; you probably have a blown fuse somewhere.
It doesn’t take much at all. I did it; and finally found the blown fuse in one of the fuse “groups” inside the cowling of my Merc outboard!

I saw your post a few days ago; but just remembered my previous problem now.

“Sorry about that Chief!”
Rick

Sights are for the unenlightened.

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