Total Frustration No restart engine

[Rontahoe]

I have a 2002 Formula 330SS with 6.3 L engines. I run this boat only at 6200ft altitude. Both engines start easily then after I take the boat out into the lake, shut the engines off, I most times have a great deal of trouble starting one or both engines. Sometimes they will start if I pump the throttle, but alot of times one engine will not start at all. Took the boat to a mechanic and he thought that it might be bad batteries affecting the computer, so replaced the batteries, same problem is happening. Help!

 

[Scott06]

I have a 2002 Formula 330SS with 6.3 L engines. I run this boat only at 6200ft altitude. Both engines start easily then after I take the boat out into the lake, shut the engines off, I most times have a great deal of trouble starting one or both engines. Sometimes they will start if I pump the throttle, but alot of times one engine will not start at all. Took the boat to a mechanic and he thought that it might be bad batteries affecting the computer, so replaced the batteries, same problem is happening. Help!

Serial numbers and maintenance history may help

If you advance the throttle in neutral will they start consistently ? If they do could be IAC valve. Other items is crab distributor cap plugs etc

Battery voltage is a issue for these engines so wasn’t a bad thing to rule out