Yamaha 9.9 Problem
Posted: Tue Oct 28, 2014 2:29 pm
All,
Greetings from your friends in the Bahamas. Dream Catcher is having a problem with one of her (2007) 9.9 Yamahas and I wondered if someone might have any suggestions.
The engine will start up and idle, even accelerate in neutral, but under any kind of load (in gear), it starts running rough and backfiring before dying out after twenty or thirty seconds. I pulled the second engine out to help troubleshoot and I now know that the carb is fine on the engine in question. I have swapped the carbs unit for unit and the problem stays with the same engine.
The engine is 7 years old, but has only 733 hours of total operation time. The oil was just changed and the level is correct and both the plugs and the fuel are new. I am about to set up the bad engine to run on a self contained fuel source via a different feeder hose with a separate fuel filtration system to verify it's not an issue with the fuel coming into the engine from the shared on board tank.
After that I may swap fuel pumps just to be certain they are both working, but after that I am running out of ideas and may have to resort to beating the engine to death with a large hammer and see if that makes any difference.
Any ideas or comments that might lead to this engines survival are greatly appreciated.
Regards,
Tom
36041
www.tendervittles.net
Greetings from your friends in the Bahamas. Dream Catcher is having a problem with one of her (2007) 9.9 Yamahas and I wondered if someone might have any suggestions.
The engine will start up and idle, even accelerate in neutral, but under any kind of load (in gear), it starts running rough and backfiring before dying out after twenty or thirty seconds. I pulled the second engine out to help troubleshoot and I now know that the carb is fine on the engine in question. I have swapped the carbs unit for unit and the problem stays with the same engine.
The engine is 7 years old, but has only 733 hours of total operation time. The oil was just changed and the level is correct and both the plugs and the fuel are new. I am about to set up the bad engine to run on a self contained fuel source via a different feeder hose with a separate fuel filtration system to verify it's not an issue with the fuel coming into the engine from the shared on board tank.
After that I may swap fuel pumps just to be certain they are both working, but after that I am running out of ideas and may have to resort to beating the engine to death with a large hammer and see if that makes any difference.
Any ideas or comments that might lead to this engines survival are greatly appreciated.
Regards,
Tom
36041
www.tendervittles.net