The low speed adjustment, It has a pin through it. It is a t shape. It should be turned out 1 1/2 turns. The high speed screw should have a black cap on it to prevent it from being adjusted more than 1/4 turn...That screw should be set at "0" turns...Lightly screw it all the way in and put the black cap back on it. To get an accurate adjustment lightly turn in the screw till it stops, or is seated, and back it out the adjustment.
Karl