11
DISPLACEMENT PUMP SERVICE
12. Unscrew the piston valve (112) from the piston valve
housing (110), taking care not to drop the piston ball
(132).
13. Remove the packings and glands from the piston.
14. Remove the cylinder (111) and o–rings (125). If the
cylinder cannot be removed easily, contact the near-
est Graco Factory Branch or Service Agency for as-
sistance.
15. Inspect the outer surface of the displacement rod
(108) and the inner surface of the pump cylinder
(111) for scoring and wear by holding them up to a
light or running a finger over the surface. Replace
these parts, if necessary. If the rod is worn, the pack-
ings will not seal properly and the pump will leak. If
the cylinder is worn, the pump will not stall against
pressure.
16. Clean all the parts in a compatible solvent, inspect
them and replace them as necessary.
17. Place an o–ring (125**) on the packing nut (140).
Screw the packing nut into the pump housing (109).
NOTE:
Lubricate the parts with a compatible lubricant
before assembling.
18. Refer to Fig 4. The gland/packing stack (159**) for
the throat is preassembled.
Do not disassemble
the stack.
Place the gland/packing stack into the
packing nut (140).
Be sure the lips of the v–packings
are facing down.
19. Place an o–ring (102**) in the groove of the wet–cup
packing nut (136). Loosely install the wet–cup pack-
ing nut (136) and the wet–cup (101) into the pump
housing (109).
Fig 4
THROAT PACKINGS
ALL MODELS
LIPS OF V–PACKINGS
MUST FACE DOWN
136
140
**125
159**
THROAT
GLAND/
PACKING
STACK
Summary of Contents for Power-Flo Series
Page 2: ......
