Displacement Pump Service

Before you start:

1.Have all necessary parts on hand. Whenever you replace the packings, also replace the glands and bearing. If you are using a repair kit, use all the parts for the best results. See the parts pages to order the kits.

2.Displacement Pump Repair Kit 206925 includes repair parts for the pump throat and piston. Parts included in the kit are marked with one asterisk, for example (6*), in the text and drawings.

3.To replace the throat packings, which are included in Repair Kit 206728, refer to the Air

Motor and Throat Disassembly on page 13.

Displacement Pump 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.

2.Relieve the Pressure

3.Disconnect the hoses, remove the pump from its mounting, and clamp the air motor base in a vise.

4.Unscrew the intake valve body (22) from the riser tube (12). See Fig. 9. Disassemble the intake valve.

5.Clean and inspect the parts for wear or damage, and replace parts as needed. Unless further service is needed, reassemble and reinstall the intake valve, using liquid sealant on the male threads. See Fig. 9.

6.Use a strap wrench on the riser tube (12) to screw it out of the air motor base (55). Carefully inspect the smooth inner surface of the cylinder for scoring or irregular surfaces. Such damage causes prema- ture packing wear and leaking, so replace the part if damaged.

7.Unscrew the piston body (13) from the piston coupling (14). Remove the ball (2*), seat (19*), gasket (6*), bearing (18*), packing (17*), and seal (16). Do not remove the press-fit brass bearing (15*). See Fig. 9.

7

55

*4

12

*4

*19

*6

*17

*15

13

7

Fig. 9

46

10

14

2*

18*

16*

22

21

3*

04212B

16 306531

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Image 16
Hitachi SERIES K, SERIES J, 206405, 206699, 206700 warranty Displacement Pump Service, Displacement Pump Disassembly