Displacement Pump - Graco GMAX II 3900 Repair Manual

Removal
1. Flush pump.
2. Stop pump with piston rod in its lowest position.
WARNING
Read Injection Hazard, page 3; Burn Hazard, page 4
3. Do Pressure Relief, page 5.
4. Separate drain hose from sprayer
F . 15
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5. Disconnect material hose from pump.
F . 16
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16

Displacement Pump

6.
F
7.
F
F
Raise latch lock. Push latch open.
. 17
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F . 18. Ratchet open pump door.
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a. Ratchet pump door forward.
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b. Twist latch u-bolt out of pump door recess.
c. Place u-bolt on pump door outer edge.
d. If pump door is stuck, do steps e., f. and 8., otherwise
go to step 9.
. 19
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Displacement Pump
310893L