I bought this ATV not running a few weeks ago and have bought parts here and there. Wiring harness, coil, new ignition switch. Got the wiring all fixed and cranking w/ spark. Everything electrically seems to work. Fuel wise I have a problem. It won't run hardly. I crank it and it doesn't fire, choke it still nada then throttle to full then let off and it will fire for a few seconds then die.

I pulled carb and cleaned the hell out of it, pulled jets carb cleaner and blew passages out with compressor. I think I have the float adjusted properly but I'm no expert. It will start if I shoot carb cleaner down the intake. I can only assume it's a fuel delivery problem but don't know where else to look. Fuel bowl is getting full too because I took a hose and hooked up to drain and ran to side of carb and opened drain screw and it was a little higher than the line of the carb fuel bowl to carb body. I don't know how high it should be.

I've tried A/F screw in every position but started out at 3 turns out and idle screw all over the place. It seems to want to run more when A/F screw all the way in. The fuel needle is in the middle position.

 

Well I just took carb back apart and used my welding tip cleaner and ran it through the jets and pulled the float needle out and blew that out too. It fires up easier choke or not but I have to feather the throttle to keep it running and eventually it dies. Thoughts?

 

Let it idle, spray carb cleaner or ether/starting fluid around intake boot, if it revs up, you got a vacuum leak, did it have an O-ring on the flange of the boot that connected to the carb? Is it installed correctly? It sounds like a fuel delivery issue but could be too much air & making the ratio go way off

 

The problem is I can't even get it to steady idle. Without feathering throttle it dies. Yeah the flange on the carb has the rubber o ring intact. And so does the black plastic piece between it and the intake. Right now the jets it has in it is a 72/35.

 

Just re-cleaned AGAIN and reset float because fuel was coming out the overflow. Same symptoms. I'm very close to just buying a new carb. It will fire a second then die, or I can keep it running by sometimes holding throttle to half or so and it will rev up.

 

Sounds like a plan, you've done everything, it must be time for a rebuild/replacement

 

Before you replace the carb Adamlc, make sure the pilot circuit in the carb is clean.. If you remove the fuel screw and spray carb cleaner in it, You need to have carb cleaner coming out of the bowl area and one of the little holes in the side of the carb bore. Also in the main jet holder there are holes in the side of it that need to be clear.

Are you setting the float so its level with the bottom of the carb?

 

I cleaned the carb extensively both jets and ran a welder tip cleaner through all the jets to ensure they are clear. Car cleaner and air seemed to run freely through all of the orifices. As far as the bowl what portion of it needs to be level with the bottom of the carb? The metal piece attached to the float where it pivots or the separating line on the float for top and bottom?

 

Just wanted to make sure the holes in the carb are clean.. As for the float.. as you hold the carb upside down with the bowl off the carb. The bottom edge of the float should be e parallel with the bowl mounting surface.

 

I got the new carb and installed it today. Started right up and stayed running. Problem solved. Thanks for the help all.