I have a honda 85 trx 250 utility. The spark plug is fouling out from a black oily substance. According to some previous post it was suggested to adjust the pilot screw. I got a Clymer manual and located the pilot screw. When I took the carb off the pilot screw is not adjustable (No notch to use a screw driver). Is this normal or should I just get another carb or drill the screw out and replace it with a new screw. Any suggestions are appreciated. Thank You.

 

Although I havent taken apart a honda carb yet, could the pilot screw have a different head pattern for a torx wrench or something else? Remember, the factory had to have screwed it in there with something. Also have you considered that your piston rings may be worn?

 

Thanks for replying. There is no head it is rounded on top. If the rings are bad it will let that much oil by. Thank You.