25hp Yamaha 2-stroke tach hookup - The Hull Truth

clearncalm · 05-02-2008, 05:12 PM

I have a 25hp Yamaha 2-stroke, bought in 2007. It has electric start and tiller steering. I would like to hook up a tach temporarily to check WOT RPMs before I buy a stainless prop. I'd like to buy a universal Teleflex tach, but the instructions don't provide enough detail on how to find the SEND wire. Could someone please guide me to the correct wire to hook up to the SEND terminal? Also, I think it is either a 6 or 12 pulse system. Does anyone know for sure?

A1 Outboard · 05-03-2008, 01:42 PM

There are several versions of the 25hp but all use a green wires from the alternator windings to the regulator if you have the electric start version. Outboard tachs use one of the AC alternator wires as a sender signal to the tach, along with a ground wire and a switched 12V wire (usually yellow).