Graymills DDP .375' Pump OMI - Manual (Page 21)

21
Service
Ball Check Valves
Tools Required
D Torque wrench
D 1/2” (13 mm) socket wrench
D O-ring pick
NOTE: A Fluid Section Repair Kit is available. See page
25 for the correct kit. Parts included in the kit are marked
with an asterisk, for example (301*). Use all the parts in
the kit for the best results. Always replace the o-rings (108)
with new ones whenever the old ones are removed.
WARNING
To reduce the risk of serious injury whenever you are
instructed to relieve pressure, always follow the Pres-
sure Relief Procedure on page 11.
1. Relieve the pressure. Disconnect all hoses. Remove
the pump from its mounting.
2. Using a 1/2” socket wrench, remove the nuts (106)
holding the top manifold (102) to the covers (101). Lift
the manifold off the pump. See Fig. 15.
3. Remove the outer o-ring (108), ball guide (202), ball
(301), seat (201), and inner o-ring (108) from each of
the covers.
4. Turn the pump over. Pull the tie rods (104) out of the
pump, leaving the four nuts (106) on the rods. Remove
the feet (107) and lower manifold (102).
5. Remove the outer o-ring (108), seat (201), ball (301),
ball guide (202), and inner o-ring (108) from each of
the covers (101).
6. Clean all parts and inspect for wear or damage.
Replace parts as needed.
7. Reassemble the intake ball checks in the bottom of the
pump, following all notes in Fig. 15. Be sure the ball
checks are assembled exactly as shown.
8. Set the lower manifold (102) and feet (107) in place on
the bottom of the pump.
9. Insert the long threads of each rod (104) through the
feet and lower manifold. Push the rods up through the
covers (101) until the nut (106) on the end of the rods
bottoms on the foot. Make sure the rods are pushed all
the way through. Turn the pump upright (the rods are a
slight interference fit and will hold the pump parts
securely in place).
10. Reassemble the outlet ball checks in the top of the
pump, following all notes in Fig. 15. Be sure the ball
checks are assembled exactly as shown. To avoid
leaks, run your finger over the o-rings (108) to ensure
that they are properly seated.
11. Install the top manifold (102) and four nuts (106).
Torque to 50 to 60 in-lb (5.6 to 6.8 N-m). Do not
over-torque.