F150 rough idle

General Boats and Motors
1

Have a 2004 Yamaha F150 that has a bit of a rough idle.
Runs perfect over 900 Rpm’s, but at dead idle it shakes more than it used to.
It has always shook a bit, but know i feel the vibration in the boat.
Just to rule out the normal issues…
plugs have 110 hours on them
burn a tank of gas a week. no water in fuel sep.
oil just changed

any ideas?
Thanks

2

Balancer Assemblys on those engines have been a problem.
Symptoms similar to yours-had mine replaced for free by dealer.
Might be worth checking it out-if memory serves, I think you mentioned the BA problem sometime ago?

Sea Hunt 2002
Yamaha 150

3

I agree with sternline. The f150 at work presented the same issue and Yamaha took care of it. If that is the issue and not corrected, BIG problems.

GW 232GT Gulfstream
150Yam x 2
“3rd Day”
Gen. Chap.1 Vs.9-13

4

fouled injector will also cause a rough idle

www.teamcharlestonmarine.com
www.joinrfa.org

5

Or what Chris said.

GW 232GT Gulfstream
150Yam x 2
“3rd Day”
Gen. Chap.1 Vs.9-13

6

BA was just replaced. Know that you mention that, it did start the rough idle right after they replaced it. Maybe they did something wrong?
Guess there is no way to check for a fouled injector.

Back to the shop it goes! (**() it!

23’ Contender F225
20’ pro-line bay Yamaha F150

7

My F90 is doing the same at idle. What was the final fix so I can narrow it down.

David M