got this quad at an auction cheap. has been sitting a while and has had someone tinkering with it before. repaired some wiring and got it turning over and firing. can get to run a little by squirting gas and cleaning jets. this carb has a clear hose near top side of carb that is not hooked up to anything. it has suction on it when i can get it to run a little by squirting gas in carb. i cannot find anyplace that looks like a tube should be there. anyone know where this line goes and what is its purpose? any help is appreciated

 

If it's got suction on the tube then probably a vacuum tube that goes to the fuel pump.At least a 2008 had one.Where it's at,don't know.2008 08 Kazuma Jaguar 500 ATV Fuel Pump | eBay

 

carb is gravity fed. reminds me of an old yamaha yz125 carb except for that hose.

 

checking around it seems these are a clone of the polaris 500 sportsman. i have been checking their carbs i see resemblence but not the hose at top. they have 3 overflow hoses. one on bowl and one on each side. mine may simply be an overflow hose. however when running and i put my thumb over the hose it starts choking down, that is why i assume it has vacuum on it

 

Polaris 4 stroke Mikuni carbs are vacuum operated with one hose going to a fuel pump,one hose is the vent so the carb can get air in the bowl chamber ,and one hose to the bottom of the carb bowl as a drain/over flow tube. If you just have one hose on the top of the carb and no fuel pump then it would seem it's just an air vent for the carb.That could explain why it dies when you block it off.Don't know what year model you have but the 2008 showed to have a fuel pump.. May have changed or didn't have one on your particular model.

 

thanks for the help old tech. as i had mentioned earlier, these quads were a polaris 500 sportsman clone. i found somewhere a mention of the carb being a keinen 32mm clone. i looked up info on that carb and found my problem. i had been cleaning the two jets i can see. the idle jet is recessed. got it clean and now idles w/out choke. the tube runs to the top of bowl probably for quick drain in case of a rollover. of course when i put my thumb over the end it prevents air from entering. the engine cant pull gas out of carb unless it is vented. i also had at half-time problem with bendix. checked polaris bendix and exactly the same. i installed a polaris bendix and now that part is good. it can be ridden now. still need to check 4x4 system and some minor electrical.

 

Curious about this engine. Send pics if you can. Mikuni carbs were used on Polaris atvs.
Never mind on the pics,found some. Does indeed look like a Polaris 500.Possibly Fugi made or a Chinese clone since they've just about cloned everything around.