I have had trouble with the truck running rich and bogging down for the last 2 weeks. I ran some seafoam through and sprayed some carb cleaner in the intake. I am sure that the choke is opening up all the way. I changed the plugs and cleaned the cap and rotor of some crud and it has improved but I still get that bogging if I accelerate too quickly. Tailpipe is a bit black and sooty. I know the mixture screw is under that plastic cap. Which way do I turn it to make it run leaner? Thanks, Ralph in Winnipeg
Not sure which truck you have but for the S80 or 81 you tighten the screw til it bottoms, but don't over tighten,just bottom, then back out 4 1/2 turns. This is initial setting and it is "righty tighty..lefty loosey". I like to use a vacuum gauge to set them highest is best.I always pop that plastic cap off and expose the brass screw.
