I have purchased two Chinese atv's and both have problems. The first starts and runs with choke on, but dies after you turn choke off. You can even ride it around with the choke on.

The other one leaks fuel from the lower vent tube on the bottom of the float bowl.

Any help would be appreciated

 

The leaking carburetor problem is most likely a stuck needle/seat valve. Often this is caused by debris from the factory assembly getting lodged in the valve so that the float can't shut off the gas flow. Sometimes the overflowing gas can spill over into the intake manifold and down into the engine. Make sure it hasn't contaminated the engine oil (smell the dipstick). Also make sure your quads have an inline filter on the incoming gas line. Add them if they don't (eBay $2.00), to keep more crud from doing this again.

On the first problem look for air leaks in the intake manfold area. Take a can of carburetor cleaner and spray around the intake manifold area while the engine is running. Any change in engine speed or engine sound indicates a leak. Else you need to disassemble the carburetor to see what is going on.

 

Don't mess with them, sell them and try to find a cheap, used, Japanese atv, I once had a piece if chinese ****, and I wore it out within one year. Just from trail riding, the clutch got fried and the choke screw that holds the choke flap in place came out and got sucked into the P-of-S engine. That little screw got smashed up by both vavles and bent the valves at the same time, then scraped a groove in the side of the cylinder after getting lodged in between the piston and the little gap between the two. All that from a little, chinese, screw. STAY AWAY FROM CHINESE ATVS[img]i/expressions/face-icon-small-mad.gif[/img]!!!!

 

<div class="FTQUOTE"><begin quote>Originally posted by: Beastly 3hundo

Don't mess with them, sell them and try to find a cheap, used, Japanese atv, I once had a piece if chinese ****, and I wore it out within one year. Just from trail riding, the clutch got fried and the choke screw that holds the choke flap in place came out and got sucked into the P-of-S engine. That little screw got smashed up by both vavles and bent the valves at the same time, then scraped a groove in the side of the cylinder after getting lodged in between the piston and the little gap between the two. All that from a little, chinese, screw. STAY AWAY FROM CHINESE ATVS[img][/img]!!!!</end quote></div>

^^ = living proof bikes require maintenance and a through going over every once in a blue moon...[img]i/expressions/face-icon-small-tongue.gif[/img]

 

I have a chinese knock-off of a 6.5 horse engine on my bandsaw mill. A friend of mine went the extra mile and put a 6.5 horse Honda on his. They look the same, start the same, run the same and parts are interchangeable. He has difficulty with his idle speed staying adjusted I have the same issue. Only main difference is may carb seems to be a little picky about fuel quality. His does not. My jets seem to plug easily. This last time we compared and I have smaller jets than he does. I am thinking of switching to the larger ones except I use less fuel and still have plenty of power.

In either case I think LynnEdwards hit the nail on the head. I would clean those carbs and check for air leaks. You can check for air leaks by starting the engine and spraying WD-40 around the carb intake while it is idling. If the idle changes then the WD-40 is getting sucked in and burned. Also you might want to start using a good fuel additive like Seafoam into each tank of ga to keep the fuel system clean.

SJ

 

Welcome to the forum diodedude! [img]i/expressions/face-icon-small-smile.gif[/img]

I would clean the carb on the one that doesnt run.

I would also ignore advice from Beastly 3hundo.

 

I have a Sunl 110 as well as my Polaris...have had some of the same problems you mentioned. Running with choke on: mine accommulated trash from the tank a couple of times, changed the fuel filter about twice and it finally stopped. It appeared to have been trash that came in it new. Also, the fuel mixture screw needs adjusting every so often, as well as, the idle screw. I have just carried a flat screwdriver with me. And finally, the fuel system cleaner Seafoam can do a great job with internal dirt. It is designed to be used at full strength for a major flush, so don't be too worried about the mixture.