Displacement Pump - Graco LineLazer II 3900 Instructions-Repair

1. Fig. 16. Flush pump.
2.
Relieve pressure; page 5.
3. Cycle pump with piston rod (A) in its lowest posi-
tion.
4. Remove suction/drain hose (27).
27
Fig. 16
See manual 308798 for pump repair instructions.
Installation
WARNING
If pin works loose, parts could break off due to
force of pumping action. Parts could project
through the air and result in serious injury or prop-
erty damage.
CAUTION
If the pump locknut loosens during operation, the
threads of the bearing housing will be damaged.
1. Fig. 19. Pull piston rod out 1.5 in. Screw in pump
until holes in bearing cross link and piston rod
align.
Fig. 19

Displacement Pump

Removal
A
Repair
1.5 in.
5. Fig. 17. Use screwdriver: push retaining spring up
and push out pin (82).
Fig. 17
6. Fig. 18. Loosen locknut by hitting firmly with a
20 oz (maximum) hammer. Unscrew pump.
Fig. 18
2. Fig. 17. Push pin (82) into hole. And push retaining
spring into groove all the way around connecting
rod.
Fig. 20. Screw jam nut down onto pump until nut
stops. Screw pump up into bearing housing until it is
stopped by jam nut. Back off pump and jam nut to
align pump outlet to back. Tighten jam nut by hand,
then tap 1/8 to 1/4 turn with a 20 oz (maximum) ham-
mer to approximately 75
Fig. 20
Fig. 21. Fill packing nut with Graco TSL, through one
of the slits, until fluid flows onto the top of seal.
Fig. 21
82
5 ft–lb (102 N m).