Yamaha F225 - 2004

[jfishking]

I have a 2004 Yamaha F225 that is idling rough, shaking/vibrating the whole boat even when not in gear. When in gear it also shakes the boat which occurs up till 2500rpm then it smooths out at cruising speed. Seems to cruise fine at 4800 rpm/ 28 knots. I recall when I just changed out the fuel filter/water separator that there was visible junk sitting on top of the filter, it was white/tannish and sort of mucousy and gummy. I may be a victim of ethanol issues, for the first time eventhough I treated the fuel before laying to boat up. Wondering if I have a clogged injector or some gum caught up somewhere. I was planning on detaching the fuel line and running a concentrated solution of ring free or seafoam and gasoline right to the engine and see if that helps. Let me know what you guys think.

Thank you,

[boats.net]

Run a compression test on engine, check prop for damage and prop shaft to see if bent, check gearcase oil to see if have metal on drain screw.
Check to see if firing on all cylinders, check fuel pressure and have injectors tested.

[Animalpharm]

I'm working with jfishking on the outboard. The problem exists while boat is idling in neutral (not in gear), so I think that would eliminate a bent prop or shaft. Also boat ran fine when taking out of water last fall for winter lay up, but may be possible damage was done over the winter. No metal shavings in gearcase oil drain screw. Boat seems to have normal power at a normal cruise speed, but I'm wondering if this sludge/gum/varnish has messed up the injector(s). I think I'll try the seafoam and if problem still exists, then get it looked into.

Thanks for help.

[mitch]

check the spark plugs as it is missing could be blocked injector ................. or it could be a shift switch you really need to hook it up to yds to see what is going on

[Animalpharm]

OK guys, figured it out. mitch and boats.net you were right on. I simply never reconnected a spark plug wire when I just changed them out. Silly me. Thanks for your help.

I will say the the engine ran (relatively) great on 5 cylinders, they are tough engines and it gives some peace of mind to know that you can get home on 5 cylinders if needed.