I wanted to let people know I found my problem.My 99 explorer 400 was not running well.It would drown out like it was getting either too much fuel or not enough fuel.I thought maybe it was jetting or a carb. problem after some help from this forum.I had a dealer go through it and they thought my clutch needed rebuilt and cleaned the carb out.Well during hunting season it kept dying out in high gear and I would have to feather the throttle to keep it running and worse case open the choke just to keep it running.I decide to give tearing the carb down a try on my own and found something very interesting.When I pulled the carb. free of the intake boot I noticed raw fuel coming out of the bottom of the main jet cover cap bolt head. Apparently it rests on a rubber block and over the period of almost seven years it had worn the hex bolt head down to about a thirtey degree angle and worn a hole through the bolt head. I could not get a new one right away so I bought some J B weld and built the bolt head back up.Well that did it.I put It back together tonight and it runs real good again.I hope maybe this helps somone out.

 

hip hip hooray! is that not so cool to have found and fix the problem and also JB weld pulls through again!

 

I'd go back to that dealer, physically show them the problem YOU had to fix because THEY missed it and demand your money back. Sounds to me they didn't even remove the carb to clean it like stated, if they had, they to would have noticed. Glad your bike is running right...I wouldn't go back to that dealer for service...

 

Had to read your post 2x cause I thought I wrote myself. had the same problem w/ 2000 exp and fixed the same way. Been 2 yrs and the weld is still holding. thank god for duct tape tie wire and jb weld