Fuel leak

[rebiuld50]

When I start the engine, the hose that runs from the top of the crankcase to the airbox pours gas out. I'm not sure what this hose is, it looks like some sort of rebreather. Could this be an issue with the petcock/ vacuum pump? I just replaced the carb, spark plug, plug wire and cdi and this is a new development.

[blue]

you are ok that Hose is for letting bad gas out of the scoot. I have mine just hanging.does not need to be hooked to anything.

[rebiuld50]

It leaks a LoT of gas, not just a random trickle. There must be a reason it started to do this

[BettinANDlosing]

Are you talking about the hose that goes from the valve cover to the airbox? If gas is coming out of there, your engine case is full of gas. Check the dipstick, most likely it will be totally full of gas, in that case you have to change your oil and check why gas is getting past the carb and filling up the crankcase.

[rebiuld50]

That's the trouble. With a new carb, where do I start to find out how the gas is getting through. Could it be the petcock?

[BettinANDlosing]

That's the trouble. With a new carb, where do I start to find out how the gas is getting through. Could it be the petcock?

Could be a petcock, did you buy a cheap china replacement carb?

[rebiuld50]

Probably. I was about $35 on Amazon. I did take it apart again and cleaned the Jets and float needle. What else should I be looking for?

[JayAre]

If you need a carb I've got the stock take off from when I big bored my wife's bike. It's a Kymco CV carb off a 2013 Agility 50 4 stroke, it has 13 miles on it. $20

[rebiuld50]

Thanks, I'll let you know if it comes to that. Also, any suggestions on oil type when I change the oil?

[JayAre]

15W40. If you can find Joe Gibbs Racing oil it has anti-wear additives/ZDP, better for the cam. Otherwise you can't go wrong with a synthetic for a couple extra $'s. Did you check the float level?

[BettinANDlosing]

Why did you ditch the Japanese Keihin for a China copy carb? The ones that come on the Agility work great.

[rebiuld50]

I salvaged the bike from an overgrown back yard. A lot of pieces were roaches and needed replacing. Even with new jets and diaphragms, I couldn't get it started with the stock carb. As soon as I put the new one in, it fired right up. It ran for a few rides, then started blowing gas back into the airbox. The fuel floats in the tank and carb are both operating correctly.

[JayAre]

You could pull the carb off feed it fuel on the bench holding the float closed to see if the needle or the needle seat gasket is leaking, make sure there is a gasket between the carb & the needle seat. Also if the floats are hollow make sure they don't have a hole, shake the float you'll hear if there's fuel in it. If it's a solid black type float push your finger on it, if you see a wet impression around the area of where you pressed your finger the float could be fuel soaked/to heavy & causing it to flood.