I have a 2001 F115 Yamaha four stroke with 850 hours on it that was idling rough.
Figured it was time for a little overdue maintenance.
I've done most of the work in the past on all my motors with very few issues.
Decided to change:
The timing belt and tensioner. Everything came off and went back in without a hitch. Located TDC on flywheel and lined up the arrows on the cam gears. Replaced belt. Adjusted tensioner. Smooth as butter.
Replaced old thermostat with a shiny new one. Smooth as butter.
Replaced the four fuel injectors. Everything came out easy-peasy and went back together again (checked the pressure in the fuel rail and had a bit over 40 psi - right in spec). Smooth as butter.
Removed the idle control valve and soaked it (completely submerged) for two days in Marvel Mystery Oil (after reading here that this method has worked for other guys). Replaced the old O ring and reinstalled the valve. Seemed smooth as butter.
Took the boat down to the water and initially it fired right up, but then it died out within moments. I was able to put the shifter in neutral and with about half throttle, was able to get the engine started, and and it ran smooth at 2000 rpm. However, every time I dropped it back down into idle/neutral, the engine would die out. Also wasn't able to get it started again in neutral.
WTF???
Could it be that soaking the idle control valve in the Marvel Mystery Oil screwed it up? I'm scratching my head thinking that - simply because it won't idle. BTW, I tried disconnecting the ICV while I had it running at high idle, but didn't notice a change - or when it was reconnected - just died out again.
Help!
Figured it was time for a little overdue maintenance.
I've done most of the work in the past on all my motors with very few issues.
Decided to change:
The timing belt and tensioner. Everything came off and went back in without a hitch. Located TDC on flywheel and lined up the arrows on the cam gears. Replaced belt. Adjusted tensioner. Smooth as butter.
Replaced old thermostat with a shiny new one. Smooth as butter.
Replaced the four fuel injectors. Everything came out easy-peasy and went back together again (checked the pressure in the fuel rail and had a bit over 40 psi - right in spec). Smooth as butter.
Removed the idle control valve and soaked it (completely submerged) for two days in Marvel Mystery Oil (after reading here that this method has worked for other guys). Replaced the old O ring and reinstalled the valve. Seemed smooth as butter.
Took the boat down to the water and initially it fired right up, but then it died out within moments. I was able to put the shifter in neutral and with about half throttle, was able to get the engine started, and and it ran smooth at 2000 rpm. However, every time I dropped it back down into idle/neutral, the engine would die out. Also wasn't able to get it started again in neutral.
WTF???
Could it be that soaking the idle control valve in the Marvel Mystery Oil screwed it up? I'm scratching my head thinking that - simply because it won't idle. BTW, I tried disconnecting the ICV while I had it running at high idle, but didn't notice a change - or when it was reconnected - just died out again.
Help!
