2010 200 ‘hunting’ for fuel

[pcconway]

Hi Folks. Newbie here. 2010 200 w 2009 pcm exe 343 5.7l engine. It’s hunting for fuel but only under load at ~18-25 mph. Seems to run OK at low and high speed. Put in some fresh fuel, sea foam and marine stabil, checked fuel in FCC and looked clean. Changed fuel filter. Seems to be getting worse. Any thoughts?

[zmnypit]

Have you checked the fuel for water?

[pcconway]

thanks for reply zmnypit. yes, drained FCC and fuel looked clean. i had a water issue with gas last year and the boat wouldn't start. we drained tank and it was fine after that. this time the boat runs fine at idle and at high speed. it's just under load around that 15-25 MPH to get to planing. i may drain tank just to be sure (but it's a pain on this model) if anyone has a suggestion on easy way to get gas out, I'm all ears! going to replace plugs Friday.

[zmnypit]

thanks for reply zmnypit. yes, drained FCC and fuel looked clean. i had a water issue with gas last year and the boat wouldn't start. we drained tank and it was fine after that. this time the boat runs fine at idle and at high speed. it's just under load around that 15-25 MPH to get to planing. i may drain tank just to be sure (but it's a pain on this model) if anyone has a suggestion on easy way to get gas out, I'm all ears! going to replace plugs Friday.

I gotcha. Did you replace the FCC filter and external fuel/water separator? Only other thing I could suggest was the high pressure pump but you said it runs fine at high speed. The easiest way I've found to drain the tank is unscrew the return fuel or vent line from the top of the tank, insert a small hose then use a drill powered pump with 5gal buckets. Still a pain in the end. Before I drained the tank I'd pick up some water finding paste, put a little on a dipstick and insert through the same lines above. It will tell you if you have water or not. Just need to make sure it reaches the bottom of the tank as water will settle there.


Hopefully you have no water and its the plugs or distributor and you're back on the water.

[pcconway]

Drained gas tank, put in some fresh fuel and changed plugs. We’re to to test fuel pressure. It’s Pouring in new England so shooting for tomorrow to test run. Thanks for the replies.

[pcconway]

Ps. We changed filter In the FCC but did not replace any pumps yet.

[MichaelD]

What makes you think it is fuel?

Is it missing when the bow is pointed up?
Over the past 2+ weeks, I was dealing with a severe missing at the kid-kneeboard speeds. (bow up)
Started at FCC, moved to pre-filter. I saw some improvement. Then moved on to replacing my 14 year old plugs, and saw some additional improvement. It wasn't until I did cap + rotor (also 14 years old) did it go back to perfect. You may need torx screwdriver for that.
I also swapped plug wires as I found evidence of arcing, but that probably wasn't required.

[pcconway]

Nice. Thanks for the insight. We’re running it today so see if any improvement w fresh fuel, new fuel filter in FCC and plugs. It was hunting even more at low rpm when I drove to launch to take it out. So has me thinking fuel (and I had similar issue last year w bad gas) . We’re checking dist cap today and will test fuel pressure when we re launch in a bit I ordered new dist cap yesterday just in case. Will keep you posted ! Thanks again.

[pcconway]

Update for anyone interested. Distributor cap had corrosion/residue. We cleaned it up (ordered new one yesterday) but launched today and boat ran great. Thanks for all the tips.