I have a white outdoors 20hp 42" deck riding mower. It has a manual pto lever. Firstly, the lever seems very stiff to turn on. Secondly, the belt just looks loose when engaged. It mows fine in the dry but sometimes I drive though a wet patch on the land and the belt slips and then smokes so I have to disengage it. I can't see anyway to tighten or move the front pulley. Is there anyway to tighten these?

A neighbor brought over a Scotts Brand mower with a 10.5 Briggs that wouldn't start. 2577 0147 01 92021431. I traced the problem to the carb, and found it full of junk. When I removed the needle valve from the inlet tube, It had a light green, foam rubber (I think) ring that stuck on the end of the needle. I could not put the needle valve back into the right position with that foam ring put back into the tube. The needle valve would not go into the tube far enough to allow the float to go into a level position if the bowl were full to spec. It was just stuck like it was wide open begging for gas, but the valve was hard up against this foam ring in the bottom of the tube. I think somebody got there first and put something in there that isn't supposed to be, but if I take this little ring out, the needle valve goes into the tube TOO far (and would let way too much gas into the bowl if left that way. Something has to go into the tube so the Needle can seal the inlet properly, but Im not sure what! I know you guys have seen everything, so I need a clue.