DISPLACEMENT PUMP SERVICE
WARNING
To
reduce the risk of serious bodily injury, in-
cluding injection, splashing in the eyes, or injury
from moving parts, always follow the Pressure
servicing any part of the spray system, when
Relief Procedure on page
5 when checking or
stalling, cleaning or changing spray tipslnozzles,
and whenever you stop
(See
Fig 3 unless otherwise noted)
1. Flush the pump with compatible solvent if possible.
Follow the Pressure Relief Procedure on page
2.
Disconnect the hoses,
the pump
its
mounting, and clamp
in
a
Unscrew
coupling nut (9) and the tie rod locknuts
and unscrew the connecting rod
from
the
Remove the cotter pin
loosen the jam
the displacement pump.
displacement rod
Pull the motor away from
NOTE:
If
are using a repair
kit to service the
pump,
use
all
the new parts even if the old
ones look good. The old parts will not seal
will leak.
See
pages
13 or
15
for the
properly with the new parts, and the pump
repair kit for your pump.
3.
the pump housing
in a padded jaw vise
4.
Remove the wet-cup
wet-cup packing nut
from the pecking nut.
and packing nut
Remove the packings
5.
Push the displacement rod
down
so
the
priming piston (119) clears the intake cylinder
6.
Use
two
wrenches to oppositely turn and loosen
the hex nuts
on the piston rod
with the outlet
against one jaw.
7. Remove the valve plate
guide
and the priming piston
8.
Remove the intake cylinder
9. Remove the u-cup packing
from the
cylinder's packing housing (REF
10. Holding onto the piston rod
pull the displace-
ment rod
through the pump housing
11. Remove the cotter pin and unthread the piston rod
(122) from the displacement rod
12. Remove the piston valve
taking care not to
drop the piston
ball
13. Remove
all the packings, washers, and
from the piston housing
14. Inspect the outer surface of the displacement rod
and the inner surface of the pump cylinder
for scoring and wear. Replace these parts,
seal properly and the pump will leak. If the cylinder is
necessary. If the rod is worn, the packings will not
worn, the pump will not stall against pressure.
15.
Clean all the parts in a compatible solvent, inspect
them and replace them
as
necessary.
TO
Fig
3
307-605
7
