Could it be a bad tach????????????????

[Alex Pullen]

I have a 1984 johnson 90horse on a 16.5ft fiberglass bass boat. I was wondering if my tach could be bad. When i got the boat and had the motor installed the tach worked then after a few months it quit, well i had new steering put on and the tach started working again. My motor stamp states 90hp @ 5500 rpm but i have never even gotten close to that, right now at WOT it will stop right on 4500rpm, so i took it to a VERY honest tech(i had a fuel delivery problem rpm fluctuated between 3500 and 4200) and he adjusted everything and couldn't believe someone put a motor together like that, anyway, after all new fuel plumbing, a fuel pump, new plugs and spark advance adjusted and some more things i dont know about, this SOB runs like a scalded dog, it has more throttle response and performance than i ever thought it could get other than the low rpm or tach problem. He said right now i am underpropped(13x15) and he says she should turn at least 6 grand with that prop but that is next on my to do list i just need to get my rpm up to correct range. This guy has 30+ years as a marine mechanic and is extremely good at what he does. I just want to know what you guys think. COULD MY TACH BE BAD?

 

[fone_man]

Re: Could it be a bad tach????????????????

Sounds like a wiring issue/loose connection that resulted in intermittant operation... Check connections with all the vibration inside a boat, wires not secured by wrapped generally work loose or corode & will cause the bove operation.<br /><br />