Can you use a hardline tach with a 3 cylinder Tohatsu MFS25B?

[bigcountry11]

I am in the process of troubleshooting a MFS25B and wanted to temporarily put a tach on the motor WOT. One to see if I am reaching 6000RPM and two, to test out a new prop DS10.

Can I order a hardline, many folks talk about and just wrap around one spark plug wire?

 

[Sea Rider]

Was wondering same for a 3 cylinderTohatsu 50 HP. Have tested many Hardline tachs on 1-2 cylinder engines none on a 3. Write Hardline and ask, Probably just intended for 1-2 cylinder engines ?

Happy Boating

 

[bigcountry11]

called hardline, said it will not work. Something about the frequency a 3 cylinder puts out doesn't jive with hardline products. Guess I wasted 34 dollars.

 

[pvanv]

That motor is intended to use an alternator tach. The $92 Tohatsu unit is intended for in-dash installation. The ECU on the MFS25/30B can tell you its RPM and other vital information (hours, temp, alarms, etc.) through the data connector. Your dealer may have the software kit to read that info. and if you are nice, they might just connect it and tell you the motor's history. In our shop, we keep a tach on hand for testing.

 

[bigcountry11]

Well, after changing the high pressure gas filter, changing all fluids and oil filter, and new prop, I think it was time to take to a professional. I will let you know the outcome