18
HIGH PRESSURE PUMP PARTS AND SERVICE INSTRUCTIONS
DISASSEMBLY SEQUENCE OF THE PUMP HEAD
Refer to the pump diagram.
1)
Remove the three discharge valve plugs and the three inlet valve plugs (32), with a 22 mm socket
wrench. Inspect the O-ring (33) for wear and replace if damaged.
2)
With needle nose pliers, remove the inlet and discharge valve assemblies (32X). Insert a small
screwdriver between the valve seat (27) and the valve spring retainer (30) to separate the valve
assembly. Remove the O-ring (31). Inspect all parts for wear and replace if necessary.
3)
Next, use a 5 mm Allen wrench to remove the 8 socket head cap screws (34). Carefully slide the
valve casing (26) out over the plungers. Remove the weep return ring (25), pressure ring (24) and
V-sleeve with support ring (23), from the valve casing (26). Remove the V-sleeve (23) from the seal
case (20). Inspect all parts, including O-ring (21) for wear and replace if necessary.
4)
Check surfaces of plunger (16). A damaged surface will cause accelerated wear on the seals.
Deposits of any kind must be carefully removed from the plunger surface. A damaged plunger
must be replaced!
5)
If the ceramic plunger (16B) is damaged, remove the plunger bolt (16C). Discard the old plunger
(16B) and copper gasket (16D) and clean the old Locktite from the plunger bolt (16C) and plunger
base (16A). Replace the plunger with the new one and Locktite the plunger bolt and torque to 120
inch-pounds.
Note: If there are deposits of any kind (i.e., lime deposits) in the valve casing, be certain that the
weep holes in the weep return ring and valve casing have not been plugged.