ok runnin along all of a sudden port motor drops about 1500 rpm, i slow down alittle check all gauges again all looks sounds fine,
i give it some throttle and the port motor lags behind and then all of a sudden bam its back to normal, hmmmm
i am getting concerned.
i turn around heading back it starts gurgling and has huge loss of power.
so i cant keep it on plane and we start to idle home.
after about half an hour or so started the motor and seemed fine??
ran for abut 15 min and got wierd again..???
then flip flopped and was fine again,, what the ??????

any ideas msp spark addon boxes?
its a 35 fountain 02 with 575's with whippleinner coolers, msd add on. etc. 200 hrs on motors.

I don't know man....
I'm just here for the "DOH!"

Check the coil and dist. cap rotor etc. I've seen the coil go bad and make that happen, it can drive you crazy. Swap coils and see what happens.

It can also be fuel. Is the motor popping and farting out of the intake? If it is than you are having a lean condition.

hmm interesting that could be it..... i think u hit on the head... lean too long, oh oh could be too bad..

water in fuel?

Number one thing I would do is swap MSD boxes. I have my own opinon of these and it's not good

I had a '93 35 Fountain w/525 SCs. Mine reacted the same way one day. Turned out it was the MSD. Swapped boxes (MSD's) like Mopower is saying and found the problem quickly. Ordered the part I needed and was back on the water the next weekend.

I had a similar problem on the port engine, it was dropping about 1000 rpm. The engine sounded fine, it just seemed to be fuel starved. Turned out I had a soft spot in the port fuel hose and it was intermittantly collapsing the inner wall. Replaced it and never had the problem again.

Dont the Fountains run individual fuel tanks to each motor ?? Id bet on the water/fuel seperater being full. Check the easy obvious stuff first.

Don't forget the anti-syphon valve at the tank. Most fuel problems can be traced to these valves. Most of the time you can just clean out the debris from the spring but I have seen small pieces of plastic that float get in the pickup and cause an intermittent condition. But I'm with InXS on this one sounds like the spark box.