I recently bought my son a 110cc quad for his christmas but we got it second hand and it has a few little problems that need sorting out.

I think it may be a chinese one but i'm not 100% it goes by the name of Thunder Kat 2 although it doesn't have any marking on it to say that.

The first problem i have is a fuel leak when the bike isnt running. Its fine when the engine is going but when you stop the engine fuel drips out from a hose (overflow?) the guy i got the bike from says this was a carbuerator problem and all he done was stick the end of the hose back into the petrol can to recycle it, this seems ok but for the time being the quad is going be in the house and it stinks. What i did notice is that if i bend the hose upwards and put a tie around it nothing comes out, but i was scared this might flood the engine so after a little while i decided to take it off again untill i find out if its ok, so i'm back to having it dripping into the can. When i did take it off the petrol ran out for a few seconds before it went to dripping again. I will be getting this looked at by a mate of mine when he has time, but for the time being would it be ok to kink the hose and clamp it or should i have it dripping into the can.


Thanks in advance.

 

Welcome and Happy Holidays.
Sounds like the fuel is still running through the carb. Adjusting the float and cleaning the jet may stop it. If that is the case kink the hose. Won't hurt anything. If it floods the carb just unkink the hose and drain the carb before trying to start again. Use to have to do this with my old trail bikes. You can put a shut off valve between the tank and carb too. Just remember to shut the fuel off when not running.

 

Thats excellent and thanks for the reply. The guy i got it from mentioned something about cleaning out the jets, but i'm very new to working on engines and things. How would i go about draining the carb if i kink the hose, I think kinking it just now while i have it in the house is my best option.

Edit. Sorry i forgot to ask i also noticed tonight that the handle bars also sit a little of from the wheels when straight is there a step by step to straighten this.

 

Welcome!

 

I can't speak for all carburetors, but the one on my neighbor's 150cc quad also had this same problem. It would drip out the overflow tube. It would also occasionally drip out the air cleaner. The thing you need to watch out for is if it also drips into the intake manifold. If it does it will run down past the piston rings and into the crankcase. When I pulled out his dipstick there was a projectile vomit of oil/gas mixture that squirted almost a foot. You don't want to run an engine with the oil diluted with gas. Smell the dipstick to see if your oil is contaminated.

Take your carb apart and clean the float needle valve and install a fuel filter if you don't have one already. As lcatv said, installing a fuel shutoff valve in the carburetor feed line is a good idea. Leaking gas is a fire hazard as well as a source of bad smells.

 

Were could i get one of these fuel shutoff valves from, I'm in the uk. If it makes a difference

 

Try eBay. Search for "fuel valve". Example:

R-Spec FUEL CUT OFF VALVE - MOTORSPORT STOCK CAR PUMP - eBay (item 370308927490 end time Dec-29-09 03:18:29 PST)

Just make sure the hose barbs are the same diameter as your fuel line.

I've seen some people use ordinary brass plumbing valves from the hardware store. It seems to work, but I would worry a little that the gas will attack the seals after a while.

 

I get my on/off valves at the local auto parts store in their lawn mower section.
Get the in-line fuel filter while your there.
Kinking the hose is not a a good idea, like mentioed, it'll fill the motor up...Clean the carb and make sure the needle and seat are clean and in good shape. Maybe adjust the float setting.

 

Thanks for the replys, I'm going to get a Fuel cut of valve and fit that and get someone to look at the carb for me. We had it out on christmas morning and the chain keeps coming off, i had a look to see if i can pull the back wheels back any but it looks like they are already back as far as they can go, so i'm now going to see if i can get a link taken out of the chain.