Graco 308550ZAD important safety instructions Reassembly Standard Diaphragms

Service

4.Unscrew one outer plate (105) from the diaphragm shaft (24). Remove one diaphragm (401), and the inner plate (104). See Fig. 13.

For overmolded diaphragms: Grip both dia- phragms securely around the outer edge and rotate counterclockwise. One diaphragm assembly will come free and the other will remain attached to the shaft. Remove the freed diaphragm and air side plate.

NOTE: PTFE models include a PTFE diaphragm (403) in addition to the backup diaphragm (401).

5.Pull the other diaphragm assembly and the dia- phragm shaft (24) out of the center housing (1). Hold the shaft flats with a 19 mm open–end wrench, and remove the outer plate (105) from the shaft. Disassemble the remaining diaphragm assembly.

For overmolded diaphragms: Pull the other dia- phragm assembly and the diaphragm shaft (24) out of the center housing (1). Hold the shaft flats with a 19 mm open–end wrench and remove the diaphragm and air side plate from the shaft.

6.Inspect the diaphragm shaft (24) for wear or scratches. If it is damaged, inspect the bearings (19) in place. If the bearings are damaged, refer to page 23.

7.Reach into the center housing (1) with an o-ring pick and hook the u-cup packings (402), then pull them out of the housing. This can be done with the bearings (19) in place.

8.Clean all parts and inspect for wear or damage. Replace parts as needed.

Reassembly – Standard Diaphragms

1.Grease the shaft u-cup packings (402*) and install them so the lips face out of the housing (1). See Fig. 13.

2.Grease the length and ends of the diaphragm shaft

(24)and slide it through the housing (1).

3.Assemble the inner diaphragm plates (104), dia- phragms (401*), PTFE diaphragms (403*, if pres- ent), and outer diaphragm plates (105) exactly as shown in Fig. 13. These parts must be assembled correctly.

4.Apply medium-strength (blue) LoctiteR or equiva- lent to the threads of the fluid-side plates (105). Hold one of the outer plates (105) with a wrench, and torque the other outer plate to 20 to 25 ft-lb (27 to 34 NSm) at 100 rpm maximum. Do not over-torque.

5.Align the fluid covers (101) and the center housing

(1)so the arrows (A) on the covers face the same direction as the air valve (B). Secure the covers with the screws (107 and 108), handtight. Install the longer screws (108) in the top and bottom holes of the covers. See Fig. 12.

6.First, torque the longer screws (108) oppositely and evenly to 190–220 in-lb (21–25 NSm), using a 13 mm socket wrench. Then torque the shorter screws (107). See Torque Sequence, page 31.

7.Reassemble the ball check valves and manifolds as explained on page 18.

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