New tachometer

[Jugfisher]

As far as I know my outboard has never had a tach on it. I have a 1981 70 Mercury. I was wondering if it was possible to put a tachometer on the motor. I bought the boat last year and the day after I bought it the water pump went out and I butned up the #1 cylinder. So I just had it rebuilt this spring and I took it out again and in 45 min the 2nd cylender went bad. That is odd b/c he rebuilt all 3 cylinders. Ofcourse as with any new motor it has a brak in period but I followed all of his instructions and it still messed up. He is honoring his warranty and fixing it again. But I want to be sure this doesnt happen again. I want to know that I am running the proper rpms. Can I put a tach on this motor with little trouble.

 

[ricksrster]

Re: New tachometer

You can put a tach on very easily. You remote control may already have the signal wire avaiable for the tach. If not, the signal wire attaches to either of the two yellow wire posts on the rectifier. A 12v+ from the key on position on the ignition switch, a ground and a light wire.
Look:
http://www.teleflexmarine.com/cgi-bin/frameset2.cgi?site=gauges&type=us&link2=1047

 

[Fishstick1962]

Re: New tachometer

Look in your key switch harness. If you see a grey wire hanging out there, it is probably your tach wire.(Not positive because of year) Just need a purple(Switched 12v) and a black(GND) and the grey hooks to the S onthe Tach, very easy. Then you need to set the Tach to the right setting. 5S or 6P is what the new ones use...not sure about the older ones. Hope this helps.
Good luck!

 

[Fishstick1962]

Re: New tachometer

OOOPS, Forgot the light wires! You can jump the purple to one side of the light bulb and the black to the other side of the bulb so your Tack will light up when the key is on.
Good Luck!

 

[Silvertip]

Re: New tachometer

Chances are the tach is not going to prevent the engine from going south again if the potential causes of the failures are not investigated. Were the carbs rebuilt as part of the engine rebuild? If not, running lean will continue to take out cylinders. So will overheat conditions so make sure the overheat sensor and warning system is working. Lack of oil will also take out cylinders.