17
308069
Service
Before you start:
1.
Have all necessary parts on hand. Always replace
the glands and bearing when replacing the packings.
Use all the parts in the repair kits for the best results
2.
Air Motor Repair Kit 206728. Parts included in this
kit are marked with two asterisks, (i.e., 36**), in the
text and drawings.
3.
Displacement Pump Repair Kit 235136. Parts in-
cluded in the kit are marked with one asterisk, (i.e.,
6*), in the text and drawings.
4.
Always use Padded pliers, p/n 207579 to grip the
trip rod without damaging its surface. Use Gauge,
p/n 171818 ensure the proper clearance between
the poppets and seat of the transfer valve.
Air Motor & Throat Disassembly
WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 8.
1.
Flush the pump and relieve the pressure.
2.
Disconnect the hoses, remove the pump from its
mounting, and clamp the air motor base in a vise.
3.
Use a strap wrench on the riser tube (12) to screw it
out of the air motor base (55).
4.
Pull the connecting rod (10) down as far as it will go.
5.
Use a hammer and punch to remove the roll pin (4).
Unscrew the connecting rod (10). See Fig. 15.
CAUTION
Do not damage the plated surface of the trip rod
(54). Damaging the surface of the trip rod can result
in erratic air motor operation. Use the special padded
pliers, 207579, to grasp the rod.
6.
Manually push up on the piston rod (41) to move the
piston assembly (59) up as far as it will go. Unscrew
the cap nut (47). Pull the nut up. Grip the trip rod (54)
with padded pliers and screw the nut off the rod. See
Fig. 15.
CAUTION
To avoid damaging the cylinder wall, lift the cylinder
straight up off of the piston. Never tilt the cylinder as
it is being removed.
7.
Remove the six screws (25). See Fig. 15. Pull the cyl-
inder straight up off the piston (59).
8.
Use a screwdriver to push down on the trip rod yoke
(28) and snap the toggles down. See Fig. 16.
9.
Remove the lockwires (34**) from the adjusting nuts
(33**) of the transfer valves. Screw the top nuts off.
Screw the stems (45**) out of the grommets (32**)
and the bottom nuts (30). Take the valve poppets
(52**) off the stems and squeeze them firmly to
check for cracks. See Fig. 16.
WARNING
To reduce the risk of pinching or amputating your
fingers, always keep fingers clear of the toggle
assemblies (N).
10. Grip the pivot pins (30) with pliers. Compress the
springs (31) and swing the toggle assembly (N) up
and away from the piston lugs (L). Remove the parts.
Check to see that the valve actuator (35) is sup-
ported by the spring clips (58), but slides easily into
them. See Fig. 16.
11. Remove the trip rod yoke (28), actuator (35) and trip
rod (54). See Fig. 16. Check the exhaust valve pop-
pets (53**) for cracks. To remove the exhaust valve
poppets (53**), stretch them out and cut with a sharp
knife.
12. Remove one muffler plate (20 or 40). Pull the piston
(59) up out of the base. Remove the throat packing
nut (42) and packings. See Fig. 15.
