Graco ULTRA 500 Instructions-Parts List Manual page 28

Displacement Pump Repair (Fig. 23 – 32)
WARNING
FLUID INJECTION HAZARD
To reduce the risk of serious injury,
follow the illustrated Pressure Relief
Procedure warning on page 12 when-
ever you are instructed to relieve pressure.
11
Fig. 23
20
Fig. 24
Removing the pump.
1. Flush the pump. Relieve pressure.
2. Remove the front cover (11). See Fig. 23
3. Unscrew the suction tube (14) from the pump,
holding a wrench on the pump intake valve (223)
to keep the pump from loosening. See Fig. 23
4. Disconnect the pump outlet hose (23). See Fig. 23
5. Use a screwdriver to push aside the retaining
spring (21) at the top of the pump. Push the pin
(20) out the rear. See Fig. 24.
6. Push the retaining spring (21) up. Push the pin
(20) out the rear.
23
223
14
21
56
01579
Disassembling the pump.
1. Unscrew the intake valve (223) and remove all
parts. See Fig. 25.
*204
*202
223
Fig. 25
2. Remove the plug (205). Unscrew the packing nut
(216). See Fig. 26.
3. Tap the piston rod (224) down and pull it out the
bottom of the cylinder (219). See Fig. 26.
4. Remove the throat packings. See Fig. 26.
205
216
*209
*213
207*
*208
Fig. 26
5. Clamp the piston rod (224) in a vise. Loosen the
nut (211). Unscrew the piston valve (222). Remove
the piston packings. See Fig 27.
224
211
Fig. 27
220
221*
02396
224
02397
222
02398