I'm having the same flooding problem with my wife's 1995 300 4x4. The carb loads up and doesn't want to idle when the engine is cold. It will start with the choke on, but as soon as you turn off the choke it dies. After starting it a bunch of times and letting it warm up it will eventually run ok though. It's been spitting fuel into the airbox. I've been through the carb at least 5 times. It got new jets, and a new float valve and seat. I checked the float level and it is good (the arms are parallel with the carb body when depressed), and I even tried bending the tab on the float arm a bit to shut the fuel off sooner and it still did floods. What else could be making the fuel flood?

Forgot to add that the bike has a new petcock, new crank seals and 125psi compression.

 

If it's spitting fuel back into the air box,then its either the carb still has problems or engine just not able to take the fuel load. 125 psi is getting down there close to minimum even if you may have new crank seals. Has the top end ever been into? Plus was the float arm and pin replaced? Just fishin again. OPT

 

The first top end rebuild was performed on the bike last year, with a wiesco piston and cometic gaskets. I just got done messing with the float arm, pin and floats. I'm thinking the floats may have been sticking. I took the caps off and cleaned the inside really good, now they slide much easier. It doesn't seem like it's flooding any more, but to get the best engine response i have the air/fuel screw turned in the whole way...Perhaps the previous owner installed too big of a pilot jet?

 

Should have #40 pilot and #155 main jet (sea level to about 3000 feet) Definitely something wrong if you have to turn the air screw all the way in! Should be around 1 1/2- 2 turns out. Plus check the slide needle. Stock is I believe 2nd position from the top. OPT

 

I know that the slide needle is in the 2nd from top position, and the main jet is a 155. I'm pretty sure the pilot is a 40, but I'll go check the pilot after the hockey game. If it is a 40, any idea of what else to check? Thanks OPT.

 

If you're sure the carb checks out and still engine won't take the fuel and still fouls plugs, spits back into the air box,still have to assume compression problem,have had pistons in the past have cracked skirts and still show reasonable compression!Pull carb, pull recoil and slowly look at the piston skirt with a flash light for any signs of seizing,galling,or damage!) or may be the seal you installed behind the drive clutch could have popped out causing the problem?? OPT