Just bought a mid to late 80s quadrunner 250 utility 4 wheeler. It starts right up but wont run long, maybe a couple minutes. I have checked all the lines and cleaned the carb really well. I have been told that the needle on the guillotine thingy wears out, lettin too much fuel in and choking it out when it warms up. Any thoughts?

 

if its flooding up it will run crappy and have black exhaust till it dies out, running out of fuel will run ok then start to rev up before it dies.
do urs do eather one?
does it start right up after it dies or letting it sit for a min.?
if so it could be ur float needle eather sticking up or leaking to much gas.

if u price it, it maybe cheaper to buy a carb rebuild kit for it then the needle set. but each machine is diff. so u should price both.

example- my brothers moto4- oem float needle assy. 20 bux or a moose carb kit which comes with the needle set and every other jet/seal- 21 bux.

 

took the carb apart again and pretty sure i found the problem. The needle that goes through the guillotine has a clip on it that holds a plastic washer that a spring pushes down on. the washer had fallen off the top and the spring wasnt puttin pressure on the needle, keeping it from seating i assume. i put it on top and put the spring back on and it runs, but not perfect.

I need to find a drawing of the carb so i can make sure i put that thing in the right place. Anyone know where i can find one?

 

bikebandit.com will have the oem part drawings for your atv. u will need to know ur exact year and model.

 

Man i sure do appreciate it! It had the schematic and i have everything together right. Just need to adjust my idle and i think im in business.

 

no problem.

 

i had the same thing happen to my 05 z250 the plastic washer broke though and it is dshooting a lot of fuel in but i think it runs better at higher rpms