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Posted

I am working on a vinson for a friend and i cant figure it out. I am getting spark. Carb has been cleaned. I soaked it for about 3 hours, rinsed, blew out passages, and re assembled. The bowl gasket could stand to be replaced but i didnt have parts at the time. I did look good enough to make a good seal though. Also, the air filter is removed. I am waiting on a new one to come in. So, when i first got the 4wheeler from him, he said it wouldnt run. i charged the battery, put some fresh gas in it and cranked it up. Next day i put a little seafoam in the tank, removed the air filter, and it wont crank. i held my hand over the intake with my fingers split to create a little suction and it still wont do anything. i've sprayed starter fluid into the intake, wont bust off. i cleaned the carb, still wont start.

i'm thinking the motor is not getting gas. also, i should add that the petcock is in the "PRI" position. Reason being is that when i disconnected the gas lines from the tank the only position that gas would run out is in the "PRI" position. when it is in the "on" or "res" position no gas runs out of the tank. Also, when i re installed the carb i put the petcock in the PRI position for about 1 minute to let the bowl fill up and i then removed the drain screw in the bowl to see if the bowl had fuel in it. It did not. No gas drained out. I checked the lines, they are clear.

also, i'm used to carbs with main butterfly and a choke butterfly. this carb has a main butterfly and some type of thing that slides up and down. what is that? how does it work? is it temp controlled?

ideas? thanks for any help!

Posted

did you try putting a small amount of gas directly in the cylinder? i know you said you sprayed starter fluid in the carb... it should have done something if there was enough spark. have you tried a new spark plug? are coils or stators known to go on these bikes do you know?

Posted

no, i havnt put any gas in the cylinder via the plug hole. also, i pulled the plug out and laid it near the plug hole and turned it over to check spark and it was sparking very well. i know jack about these machines.

what is that big thing that slides up and down inside the carb throat? some type of choke? i'm not talking about the throttle butterfly.

Posted

The fuel system on that is a pressurized system. Prime forces gas threw . Check the fuel lines. get a squirt bottle and shot a little gas in it (try it out of the prime mode) . When you do get it to run, take it out of the prime mode.

Posted

Just a suggestion. I had a similar problem with my 02'...No start, acted like it was flooding, had great spark...It really had me stumped. Just for sh**s and giggles I swapped in a brand new plug and it fired right up. Just because you see a spark on the plug while its out doesn't mean it's sparking across the electrode where it's most needed in the combustion chamber. Just sharing an experience. I had mine tore down pretty bad and it ended up being a simple thing. It's worth a shot.

Posted
Just a suggestion. I had a similar problem with my 02'...No start, acted like it was flooding, had great spark...It really had me stumped. Just for sh**s and giggles I swapped in a brand new plug and it fired right up. Just because you see a spark on the plug while its out doesn't mean it's sparking across the electrode where it's most needed in the combustion chamber. Just sharing an experience. I had mine tore down pretty bad and it ended up being a simple thing. It's worth a shot.

absolutely worth a shot!!

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