5 • Service
Doc. 155028-01 08/20
77
3. If this is the
primary
pump head, install a 10-32 fitting plug (P/N 042772) on
the outlet check valve. Tighten the plug.
If this is the
secondary
pump head, install a 10-32 fitting plug (P/N 042772)
in both the inlet and outlet ports. Tighten the plugs.
4. Push the piston into the pump head. (This should hydraulically unseat the seal
from the head.) Remove the piston and pull off the seal.
NOTE If the piston seal is not removed, make sure the 10-32
fitting plug(s) are tight and add more water. Make sure
the pump head contains no air bubbles, and then repeat
Steps
5. Remove the 10-32 fitting plug(s).
To install the new piston seal:
1. If this is the
secondary
pump head, open the waste valve knob by turning the
knob one-half turn counterclockwise.
2. Lubricate the seal and the pump head
opening with a small amount of isopropyl
alcohol to facilitate insertion.
3. Push the piston through the spacer and
then through the new piston seal.
4. Insert the piston and seal into the pump
head.
Piston Seal
Spacer
Piston
