Boat is a 2556 with 5.7 (600hrs) and Volvo Duo Prop and has run with no mechanical issues for 7 seasons (100hr per) it gets all required PM. It developed a problem last fall. After running for 45min to an hour boat would not accelerate past 3200. I would get a slight pop pop(backfire?) sound as I try to accelerate. Did some trouble shooting and retesting after changing fuel filters, distributor cap, rotor, checked compression, checked for restricted exhaust, the fuel is new, plugs 1 season and look good and the carb was rebuilt 3 seasons ago, and had the same issues. Checked the timing and noticed it was retarding checked for distributor movement, nothing but ended up replacing distributor since mechanical advance mechanism look questionable.
The boat will now run good for about an hour then nothing above 3200rpm the timing is staying put still get the pop pop sound when trying to accelerate.
What to look for next?
The boat will now run good for about an hour then nothing above 3200rpm the timing is staying put still get the pop pop sound when trying to accelerate.
What to look for next?
