Check Valve Adjustment - Graco GT 750 Instructions Manual

Service

Check Valve Adjustment

This pump has an adjustable piston ball check.
To change the piston ball travel:
1. Relieve pressure, page 6.
2. Loosen nut (5).
3. Turn the piston valve housing (6) counterclockwise
to increase the ball travel and clockwise to
decrease the ball travel.
NOTE: The factory setting is a 0.225" ball travel.
Decreasing the ball travel can minimize surging at
stroke changeover; however, a travel that is too
short restricts the flow and slows down the pump.
F . 15
IG
4. Tighten nut (5). Torque to 60 ft-lb (81.35 N•m).
12
5
6
3A5363B