Ok, 1999 Yamaha Wolverine 350

So , I replaced the carb because the old one broke while I was trying to get the pilot screw out. It came in today and I set the pilot screw to 2 and 1/2 turns from seated. I got it to start. After a few cranks and blocking the air box so it would suck fuel in to the bowl, it finally started. AT first the throttle was a bit low so I turned the throttle stop up a bit until I felt it was in or near the 1000rpm idle range per the manual says. I dont have tach, I just guessed.

So now that I have it started, it will run a bit on idle good, no hesitation or popping. Then just POP and die. I can see that it backfires through the Carb. I think. When it pop and dies, I can see the carb move a bit. When it dies, I can start it right back up, run for about 30 sec and then POP dies. I can run the throttle up , doesnt die there... just when at Idle.

When I put the top end back together, I made sure the marks were lined up on the cam sproket with the tick mark on the head as well as the T mark below.

So question is : whats causing it to die and back fire through the carb?

 

No one has any info?

 

since it is starting right back up, spark is good, maybe you need to recheck the float level to make sure you are not flooding it. or possibley the fuel petcock is partially plugged, and the quad runs for 30 sec, runs out of fuel, dies, then enough trickles in to refill the bowl to let it restart. Try taking the fuel line off and opening the petcock, you should see a good steady stream of gas, or even try the reserve position, to see if that flows better.

 

Thank you for your reply. I'll check it.

 

If it flows gas as it should, then I'd bet on the float level being the problem... It should be set as directed in the manual... Usually just so it cuts off gas when the float is level if you hold it up. I usually blow air through it with my mouth and work the float and have someone watch and see if its level when it stops letting air pass through. Cheap easy way to check it...

Also, is this a new carb or was it a used one? IF it was used, you could still need to clean it up. They clog very easy.