Joe_the_boatman
Chief Petty Officer
- Joined
- Apr 14, 2005
- Messages
- 482
I'm trying to give new life to this little neglected motor that I paid $60 for.
In a bucket, it idles great and revs fine to 1/2 throttle. Past 1/2 throttle it bogs down, and will run no faster. When I intentionally starve the carb of fuel, it revs higher right before cutting out (like most two strokes). This led me to believe there's a fuel delivery problem, but I've gone through the carb multiple times and it's super clean. This is a slide carb, with a needle jet, and everything appears to be in working order there.
I ran a temporary fuel line directly to the carburetor to take the fuel tank, lines, filter, and valve out of the equation, and nothing changed.
I don't see anywhere where there could an air leak downstream of the carb, and it fits snug on the intake.
If the fuel system isn't causing this, maybe it's the ignition not advancing at higher throttle? (Even though it revs higher when it runs out of fuel?)
I have not changed the spark plug, but see no reason to yet. I haven't messed with slide carbs since my motorcycle days 20 years ago, but this is a very simple device. The only adjustment is the idle speed screw (not a mixture adjustment, it adjusts the slide's bottom position).
I searched, but haven't found much info out there on messing with these little engines.
Any thoughts?
In a bucket, it idles great and revs fine to 1/2 throttle. Past 1/2 throttle it bogs down, and will run no faster. When I intentionally starve the carb of fuel, it revs higher right before cutting out (like most two strokes). This led me to believe there's a fuel delivery problem, but I've gone through the carb multiple times and it's super clean. This is a slide carb, with a needle jet, and everything appears to be in working order there.
I ran a temporary fuel line directly to the carburetor to take the fuel tank, lines, filter, and valve out of the equation, and nothing changed.
I don't see anywhere where there could an air leak downstream of the carb, and it fits snug on the intake.
If the fuel system isn't causing this, maybe it's the ignition not advancing at higher throttle? (Even though it revs higher when it runs out of fuel?)
I have not changed the spark plug, but see no reason to yet. I haven't messed with slide carbs since my motorcycle days 20 years ago, but this is a very simple device. The only adjustment is the idle speed screw (not a mixture adjustment, it adjusts the slide's bottom position).
I searched, but haven't found much info out there on messing with these little engines.
Any thoughts?