Recirculation / Over Pressure Relief Block; Air Motor - Graco Reactor A-20 Repair Parts

Recirculation / Over Pressure
Relief Block
Valves can be serviced with the block on the machine
(see page 32 for parts view). For thorough cleaning,
remove the block assembly as follows.
1. Remove both rear shrouds and lower front shroud;
see page 12.
2. Disconnect two fluid tubes connected to back of
recirculation block.
3. Loosen and remove two screws (ST) in back of
recirculation block.
ST
4. See Relief Manifold, page 30. Clean and inspect all
parts for damage. Ensure that the seat (8a) and
gasket (8b) are positioned inside each valve car-
tridge (8).
5. Apply PTFE pipe sealant to all tapered pipe threads
before reassembling.
6. Reassemble in reverse order, following all notes.

Air Motor

See A-20 Air Motor Pump Assembly on page 32.
Air Motor Seal Repair Kit 255057 is available to
change all air motor seals.
1. Remove four cover bolts (404) from outside hous-
ings (402). Leave fan connected.
311512A
2. Raise retaining spring (444) and knock retaining
pins (436) out of pump rod slots. Leave yoke (415)
and link (414) in place.
3. Press in tube fitting ferrules and pull out tubing to
disconnect air lines.
4. Remove four bolts (408) to remove entire air motor
assembly.
ti8485a
5. Remove lock nut (434) from piston rod (437) and
remove pump yoke (415).
6. Remove four lock nuts (409), washers (407), and
tie-rod bolts (408).
7. Lift top plate (406) and remove from air cylinder
(405).
8. Push piston rod assembly out of the air cylinder and
replace piston o-ring (438) and lubricate.
9. Replace bottom plate bearing (434), u-cup seal
(435), and lubricate. U-cup seal open end faces up.
10. Replace top and bottom o-rings (439) in the plates.
Use lubricant to hold in place.
11. Assemble in reverse order.
12. Torque tie rod bolts in small increments evenly to
17-22 in/lbs (3•4 Nm).
402
ti8491a
408
406
405
437
415
ti8457a
Repair
434
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