Hello! I have just gotten my hands on a 2009 Sea Hunt Ultra 186 with a 2009 Yamaha F115 TLR that has been stalling out. The boat when in WOT will slow way down, try to rev it self back up, slow way down again, then cut off. The bulb is almost always drawn completely flat.Eventually the boat won't work with anything above an idle. I have tried and tried to fix this and i am still having issues. Any help is very much appreciated! Here is my timeline:
Boat has not been driven much at all in the last 5 years by previous owner. Issue started about 2 years ago and has barely been driven at all since then.
Previous Owner replaced fuel line to the primer bulb, the bulb itself, and line from the bulb to the engine
Drove the boat and it stalled at WOT and engine cut off within about 5 minutes of taking off.
Pulled Pick-Up tube from tank (No screen or clog)
Replaced the Anti-Siphon Valve
Replaced the fuel line from ASV to Fuel/Water Separator
Replaced the Fuel/Water Separator (emptied and gas was gross, reddish gel like with mostly water)
Ran boat and exact same thing happened within 5 minutes
Mechanic drained Gas tank,
Fuel System flush and cleaned injectors
Normal 100 hr service
Primed with non ethanol
I Filled tank halfway with non-ethanol gas (to get as close to the same situation as possible) and added a little StaBil Marine 360
Boat ran fantastically at WOT or half throttle or idle for about 1.5 hours. Then same issue started.
Emptied the Fuel/Water Separator and there was some water and a little debris (Mechanic said to keep emptying that after the first few runs to get anything they couldnt get from the tank)
Took it out again and boat ran great for almost 3 hours, same issue started. Emptied the separator and there was some water but better. And i could go again for a while. This happened about 4 times this day and by the end of it the gas was clean and had no water. But the problem happened again and eventually could not go anymore above idle.
Took it out again and ran great for about 2 hours. No problems.
Took boat out again at almost a full tank (added a little more StaBil). Ran great for about 2 hours, and problem happened once, (emptied Fuel water separator, looked clean, and got going again), then a 2nd time about 20 minutes later and had to idle back.
A few other notes:
I have not had any trouble filling gas tank up, no gas spewing back unless it is completely full.
I have tried opening the filler cap and it has not helped the problem.
The combination Fuel vent/Filler cap is not corroded or clogged.
When I unscrew the Fuel water separator, it sucks in air sometimes and the bulb re-inflates.
I have also emptied the fuel filter on the engine throughout this and there has never been any water or debris in it.
Should I replace the Anti-Siphon valve again, since i originally replaced it before I got rid of the bad gas?
Am i screwing up by taking this separator off and re using it numerous times? I planned on replacing that today regardless.
The fuel water separator housing is the only thing not new from the tank to the engine....do those ever need to be replaced? It looks...11 years old. Ha.
Sorry for the lengthy post, I just don't know where to go next...
Thanks again.
Boat has not been driven much at all in the last 5 years by previous owner. Issue started about 2 years ago and has barely been driven at all since then.
Previous Owner replaced fuel line to the primer bulb, the bulb itself, and line from the bulb to the engine
Drove the boat and it stalled at WOT and engine cut off within about 5 minutes of taking off.
Pulled Pick-Up tube from tank (No screen or clog)
Replaced the Anti-Siphon Valve
Replaced the fuel line from ASV to Fuel/Water Separator
Replaced the Fuel/Water Separator (emptied and gas was gross, reddish gel like with mostly water)
Ran boat and exact same thing happened within 5 minutes
Mechanic drained Gas tank,
Fuel System flush and cleaned injectors
Normal 100 hr service
Primed with non ethanol
I Filled tank halfway with non-ethanol gas (to get as close to the same situation as possible) and added a little StaBil Marine 360
Boat ran fantastically at WOT or half throttle or idle for about 1.5 hours. Then same issue started.
Emptied the Fuel/Water Separator and there was some water and a little debris (Mechanic said to keep emptying that after the first few runs to get anything they couldnt get from the tank)
Took it out again and boat ran great for almost 3 hours, same issue started. Emptied the separator and there was some water but better. And i could go again for a while. This happened about 4 times this day and by the end of it the gas was clean and had no water. But the problem happened again and eventually could not go anymore above idle.
Took it out again and ran great for about 2 hours. No problems.
Took boat out again at almost a full tank (added a little more StaBil). Ran great for about 2 hours, and problem happened once, (emptied Fuel water separator, looked clean, and got going again), then a 2nd time about 20 minutes later and had to idle back.
A few other notes:
I have not had any trouble filling gas tank up, no gas spewing back unless it is completely full.
I have tried opening the filler cap and it has not helped the problem.
The combination Fuel vent/Filler cap is not corroded or clogged.
When I unscrew the Fuel water separator, it sucks in air sometimes and the bulb re-inflates.
I have also emptied the fuel filter on the engine throughout this and there has never been any water or debris in it.
Should I replace the Anti-Siphon valve again, since i originally replaced it before I got rid of the bad gas?
Am i screwing up by taking this separator off and re using it numerous times? I planned on replacing that today regardless.
The fuel water separator housing is the only thing not new from the tank to the engine....do those ever need to be replaced? It looks...11 years old. Ha.
Sorry for the lengthy post, I just don't know where to go next...
Thanks again.
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