Tachometer

[Justin Fenwick]

I have installed an old Yamaha tacho but it is on a 75 mariner 3 cyl and quicksilver box. I am pretty confident that the wiring is correct but there is still no reading.

[robert graham]

I have installed an old Yamaha tacho but it is on a 75 mariner 3 cyl and quicksilver box. I am pretty confident that the wiring is correct but there is still no reading.

Assuming your in-line fuse or breaker is O.K.? There is a small slot-head screw on the back of tachometer...with motor running take a small screwdriver and move that screw back and forth a few times while checking for correct reading. Doublecheck those wiring connections on the back of tachometer. Moisture has been know to find it's way into a tachometer and ruin it, requiring replacement.

[Justin Fenwick]

It is a very old Tacho.There are 4 posts on the bottom

12 B 6 then its separated and has a G on the next

I have been through a wiring diag and shows that all is connected properly and I'm even getting the illumination i am told that it was working fine before.