tach on a '94 2 stroke 15 hp

[baja power]

I posted this in the Johnson forum, but it was suggested i post here since not that many people surf the johnson forums..


When it comes to O/B's, i'm not the guy to go to (big power, high displacement I/O are another story.. However I just picked up a RIB to use as a tender for the larger boat. Love it to death. The 15hp Johnson 2 stroke pushes it right along. Although there is no instrumentation, i wish to put a tach on it so i know what i’m turning in order to do some prop testing and get this thing dialed in. My question is can you put a tach on this motor? And if so how would you go about it? Would i need a special tach since its 2 stroke or only 2 cyl?



NOTE: yes im aware of the " tiny tach" and i see it useless since it only refreshes once every 2.5 seconds..

 

[ricksrster]

Re: tach on a '94 2 stroke 15 hp

Do you have a charging system for your battery? If so it is wired to any one of the following: yellow, yoellow/grey, or grey on the terminal block or one of the wires from the alternator stator. That will be your send wire on the tach. The other wires on the tach are 12v+ from ignition switch, ground, and light. iboats sells tachs. Johnson's under 70 hp are 10 pole 5 pulse. See http://ww2.tflx.com/PDF/99320.pdf for instructions.
If you do not have a charging system, then Tiny Tach is recommended.

 

[baja power]

Re: tach on a '94 2 stroke 15 hp

it's a pull start so no charging system..