Waters Prep Series Installation And Maintenance Manual page 140

Dual check valve assembly
Outlet check
valve housing
Removing the pump head
The figure below is an exploded diagram of a pump head.
Pump head disassembly
Plunger bearings
Pump seal
PUMP SEAL
PUMP HEAD
To remove the pump head:
1. Shut down the controller, and disconnect the power cord. The
proportioning valve stops all solvent lines.
2. Disconnect the inlet line from the inlet check valve. If necessary, use a
5/16-inch wrench to loosen the inlet line. Let solvent drain onto an
absorbent wipe.
3-56 Troubleshooting, Testing, and Maintenance
Seat
Seal guide
Pump head
Outlet check
valve housing
Seat
Ball
Seal guide
ALLEN SCREW
Hex-head screws