Hi -- having some engine problems and this seems like a good place for advice...
We have a 1999 200hp Yamaha 2 stroke. Engine runs well, has only 250 hours.
The other day, after hitting some waves, I noticed the boat slow down slightly while going down the wave. Thought it was cavitation, but it got worse with each wave we hit, becoming a sudden deceleration each time. Eventually, the loss of power would last beyond the wave, and even after we were through waves, the boat would have power issues. Now, the problem is permanent, and if you accelerate quickly, the boat will lurch to idle, then reaccelerate, then lurch again. However, if you accelerate very slowly in flat water, the boat runs 100% fine, up to almost full throttle where it will cut out again. Once it cuts out it will keep cutting out every 5 seconds until you take off the throttle.
It seems to me like a fuel issue - maybe fuel flow, water, or air in the lines. We've added Sea Foam fuel stabilizer (haven't checked the fuel filter yet, it's hard to access). When the problem started, we had an empty tank, but have refilled and it is still happening.
Any ideas? Thanks!
We have a 1999 200hp Yamaha 2 stroke. Engine runs well, has only 250 hours.
The other day, after hitting some waves, I noticed the boat slow down slightly while going down the wave. Thought it was cavitation, but it got worse with each wave we hit, becoming a sudden deceleration each time. Eventually, the loss of power would last beyond the wave, and even after we were through waves, the boat would have power issues. Now, the problem is permanent, and if you accelerate quickly, the boat will lurch to idle, then reaccelerate, then lurch again. However, if you accelerate very slowly in flat water, the boat runs 100% fine, up to almost full throttle where it will cut out again. Once it cuts out it will keep cutting out every 5 seconds until you take off the throttle.
It seems to me like a fuel issue - maybe fuel flow, water, or air in the lines. We've added Sea Foam fuel stabilizer (haven't checked the fuel filter yet, it's hard to access). When the problem started, we had an empty tank, but have refilled and it is still happening.
Any ideas? Thanks!