Boats runs, then sounds bad and won't run! Help!

[Kateh]

My 1999 Mobius has been doing a similar thing, but feels
Like it is choking out while pulling a skier. High speeds and high RPMs will bring it on after about 4 hrs of use. It never dies tho... Just kind of surges. Surfing and wakeboarding don't seem to affect it. It has no problems starting. Put in a new carburator, thinking that was the problem with no change. New high power fuel pump too. Sea foam, Heet, and ethanol free fuel. Does anyone have any ideas?

[brain_rinse]

My 1999 Mobius has been doing a similar thing, but feels
Like it is choking out while pulling a skier. High speeds and high RPMs will bring it on after about 4 hrs of use. It never dies tho... Just kind of surges. Surfing and wakeboarding don't seem to affect it. It has no problems starting. Put in a new carburator, thinking that was the problem with no change. New high power fuel pump too. Sea foam, Heet, and ethanol free fuel. Does anyone have any ideas?

You've already replaced the big ticket items so may as well do the smaller maintenance things if you haven't already: fuel filter, rotor/cap, plugs and wires.

[zabooda]

My 1999 Mobius has been doing a similar thing, but feels
Like it is choking out while pulling a skier. High speeds and high RPMs will bring it on after about 4 hrs of use. It never dies tho... Just kind of surges. Surfing and wakeboarding don't seem to affect it. It has no problems starting. Put in a new carburator, thinking that was the problem with no change. New high power fuel pump too. Sea foam, Heet, and ethanol free fuel. Does anyone have any ideas?

My 98 never had high speed issues but I've had the engine sporadically cutting out and then back in at different rpms. I replaced the electronic ignition twice in the boat in a span of 10 years and each time it fixed the problem. The second time I thought it was a carb issue and had it rebuilt which it probably needed after 15 years of use. No vapor lock here.