Fuel Leak-Valve?

[splinterddt]

Okay, here's the low-down. A few months ago, I bought a 2008 Wildfire 50cc scooter for my step-son to get around. It had some cometic issues but it runs. I didn't get a close look at it before buying, and found the previous owner had made "repairs" to the wiring. After several days, I got the wiring staightened out. Kid was going to an appointment and couldn't get it started, and it was leaking gas. When I was able to check it, I found he had the kill switch on and the gas was leaking out of the air box. I tried to start it, but gas just poured out of the air box. I figured there was an issue in the carb, so I took it off, took it apart, cleaned it out, and reinstalled it. I primed the carb according to the service manual. The scooter tried to start, but started pouring gas out of the air box again. I disconnected the vacuum line to the fuel valve and there was a little gas in the line. I attempted to start it again, and this time to fired up. When I tried to plug in the vacuum line, the scooter would die. I pulled off the line and started the scooter. Again noticed gas in the line, but when I suck on the line to prime the carb I get no gas on the vacuum side. I noticed the breather hose that goes from the valve cover to the air box was wet, so I disconnected it at the valve cover. When I started the scooter again, and got the vacuum line connected without it dying, after a few seconds fuel was shooting out of the beather at the valve cover. I'm guessing that the fuel valve must be malfunctioning, allowing fuel into the vacuum side. Before I get a replacement valve, I wanted any opinions you might have.

[rks]

Have you pulled the dip stick? Sounds to me like the crankcase is way, way, way over full. (not necessarily all oil)

I can't see any way you could get gasoline to come out of a crankcase breather tube....unless it is a gravity feed fuel system, and the carburetor float is stuck open. If your tank is higher than the carb, and you have a petcock (as you stated), then both the petcock and the float would have to fail, so gas could flow thru the carb, into the cylinder, past the rings, and into the crankcase, so if could be pushed out thru the breather.

Sounds like it's going to need a new air filter too.

[splinterddt]

That's the funny thing. When I found the gas coming out the breather tube, I checked the oil and the crank case is at the normal level. In fact maybe a little low. The tank is higher than the carb. There is no real petcock, just the vacuum operated fuel valve. Since there is fuel getting in the vacuum side, that's why I'm guessing the valve is bad. Unless someone has a different idea.

[rks]

If you are getting fuel on the vacuum side, and all lines are connected to the proper ports, then it is a faulty fuel valve (petcock). This still doesn't explain fuel coming from crankcase breather. (unless your lubricating oil is actually half gasoline)...It is normal to have some moisture laden gases coming from there, that condense into a liquid as they cool off. (see pics in my profile, photos) I collected .45oz, in my little green catch can, but that was over 1200 miles of operation. I know it kind looks like gas, but it is 95+% water, and a couple of drops of oil. Don't know how your engine would ever start, let alone run, if rings are worn enough to let gasoline into the crankcase and out the vent, while engine was running. Has to be leaking thru the system and by the rings, when scoot is not in use.

[splinterddt]

Okay, finally got a new fuel valve and got time to install it. Drained the oil, which was mostly gas. Got everything filled back up and started the scooter. No issues with gas in the breather tube. Made sure everything was hooked up and took it for a test ride. No issues! I'll keep an eye on it for a few days, but I think the fuel valve fixed the problem.

[rks]

How about that....sounds like you're good to go.

Also, nice that you took the time to post a conclusion to your problem.....so many folks don't...Scoot Safely