Line Pressure

An incorrect throttle pressure setting will cause incorrect line pressure readings even though line pressure adjustment is correct. Always inspect and correct throttle pressure adjustment before adjusting line pressure.

Fig. 13 Measuring Spring Retainer Location:

NOTE: Before adjusting line pressure, measure distance between manual valve (valve in No. 1 low position) and line pressure adjusting screw, Fig. 13.


This measurement must be 15/16 inch. Correct by loosening spring retainer screws and repositioning spring retainer. The regulator valve may cock and may hang up in its bore if spring retainer is out of position.

If line pressure is not correct, it may be necessary to remove valve body assembly to perform the adjustment. The approximate adjustment is 1 5/16 inch measured from valve body to inner edge of adjusting nut. However, due to manufacturing tolerances, the adjustment can be varied to obtain specified line pressure. The adjusting screw may be turned with an Allen wrench. One complete turn of the adjusting screw changes closed throttle line pressure approximately 1 2/3 psi. Turning adjusting screw counterclockwise increases pressure, and clockwise decreases pressure.