How do adjust the carb. on a '99 Explorer 400? How do I identify the adjust screw. I know where the idle adjust is but not the others.

 

There is one small adj screw just aft of the idle adj screw. It's for the 0-1/4 throttle mixture. Turning it out leans things out, and turning it in richens things. The other adj are made with the clip postition on the needle...lower the clip, the richer the 1/4-3/4 throttle mixture. The main jet controls things from 3/4 to Wide Open Throttle (wot)

Ken

 

Thanks Ken. I think all I need is a slight adjustment of the mixture. We have been changing plugs to fix a hesitation problem. There are times when it wants to sputter when climbing a steep mountain.