Waters Prep Series Installation And Maintenance Manual page 146

3. Pry the piston cap out of the piston, using a wire whose end is formed
into a small hook. Insert the hook behind the cap and pull it toward you.
Exposed plunger and piston
4. Insert the plunger insertion tool into the piston cavity. With one hand,
force the inner part of the plunger insertion tool against the snap ring.
Using a pair of snap-ring pliers, squeeze the snap-ring to release the it
from the piston. The snap ring, washer, and spring will hang freely on
the plunger rod.
3-62 Troubleshooting, Testing, and Maintenance