I have a 2004 Yamaha 30HP 4 stroke that has been giving me fits the last two years.
Two springs in a row on initial start up the carbs appear to be leaking gas fron the air/fuel mixture ports. Both times I took it to a different shop and both times they could not get it to leak gas.This year I took video on my phone to show the mechanic. Both times each shop could not find a problem and said it ran great.They both said it ran great in their tank.
Both years on the lake the engine intermittently idles rough and stalls. It always starts right back up after stalling. When I use the the fast idle, it runs great but when I put it in gear it stalls or stumbles. If I get past the stumble/stalls it takes off and runs great when the rpms are up. When I slow back down towards idle it then repeatedly stalls and doesn't want to run for a while (it will start and idle although sometimes rough). Yesterday I could smell gas but couldn't see a leak after it stalled. I had to paddle the last 50ft to the dock because it would kill every time I put it in gear.
I love this motor when it runs but I've lost my patience.
Please help!
Update: I had the hood off yesterday and was running it on the hose. Tried different idle positions with no luck, I noticed that while in neutral, if I moved the carb linkage slightly, I would hear a slight air hiss before it began to stumble/stall. Is this normal? If not, what should I be checking?
Two springs in a row on initial start up the carbs appear to be leaking gas fron the air/fuel mixture ports. Both times I took it to a different shop and both times they could not get it to leak gas.This year I took video on my phone to show the mechanic. Both times each shop could not find a problem and said it ran great.They both said it ran great in their tank.
Both years on the lake the engine intermittently idles rough and stalls. It always starts right back up after stalling. When I use the the fast idle, it runs great but when I put it in gear it stalls or stumbles. If I get past the stumble/stalls it takes off and runs great when the rpms are up. When I slow back down towards idle it then repeatedly stalls and doesn't want to run for a while (it will start and idle although sometimes rough). Yesterday I could smell gas but couldn't see a leak after it stalled. I had to paddle the last 50ft to the dock because it would kill every time I put it in gear.
I love this motor when it runs but I've lost my patience.
Please help!
Update: I had the hood off yesterday and was running it on the hose. Tried different idle positions with no luck, I noticed that while in neutral, if I moved the carb linkage slightly, I would hear a slight air hiss before it began to stumble/stall. Is this normal? If not, what should I be checking?
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