Introduces Doosan DL220 Power Steering System CLEANING AND INSPECTION

   This article mainly introduces Doosan DL220 Power Steering System  CLEANING AND INSPECTION

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1. Install springs in spool slot. See Figure 48. Springs must
be positioned as shown in Figure 49.

2. Position springs so that amount of spring protruding out of
spool is equal on both sides. See Figure 50.

3. Insert spool into sleeve. See Figure 51. Use care so that
sleeve and spool are correctly assembled. The spring slot
in sleeve must align with spring slot in spool. Also, one of
the T shaped slots (A) in the spool must align with one of
the small holes (B) in sleeve. See Figure 52.

4. Center springs in sleeve. See Figure 53.

5. Install seal ring on sleeve. See Figure 54. Burnish seal ring
with a smooth object until seal does not protrude past
diameter of sleeve.

6. Rotate seal ring. See Figure 55. It must rotate freely

7. Turn sleeve 180°. Install cross pin into sleeve and spool.
See Figure 56.

8. Install two thrust washers and thrust bearing over end of
spool. See Figure 57. The sequence of the parts
installation is shown in Figure 58.

9. Oil O-ring and backup ring and then install them on an Oring assembly tool. See Figure 59.


without resistance

10. Insert assembly tool down into bore of steering unit. See
Figure 60

11. Use assembly tool to install O-ring and backup ring into
bore. See Figure 61.

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12. Unbolt housing from stabilizing base. Hold housing in a
horizontal position. See Figure 62. Insert sleeve and spool
into bore.

13. The sleeve will push the O-ring and backup ring into
correct position. See Figure 63.

14. Bolt housing back into stabilizing base. See Figure 64.

15. Insert ball into hole. See Figure 65.

16. Install threaded bushing into hole that ball was placed into.
See Figure 66. Lightly tighten bushing. The top of the
bushing must be lower than the surface of housing.

17. Lubricate O-ring with 20 weight mineral oil and install it in
groove. See Figure 67.

18. Install middle plate onto housing. See Figure 68. Be sure to
properly align plate holes with holes in housing.

19. Lubricate O-ring with 20 weight mineral oil and install it in
groove. See Figure 69.

20. Install distributor plate. See Figure 70. Be sure to properly
align plate holes with holes in middle

21. Install shaft into bore of housing. See Figure 71. Position
slot in shaft to engage cross pin

22. Position rotor so that cross pin is between two teeth as
shown by position of screwdriver. See Figure 72.

23. Lubricate two O-rings with 20 Weight mineral oil and install
them in grooves of cylinder gear. Slide cylinder gear into
position on housing. See Figure 73.

24. Use a bolt to align holes in cylinder gear with bolt holes in
housing. See Figure 74.

25. Install spacer bushing. See Figure 75. Remove bolt that
was installed in previous step (If equipped.).
OSPL 630:1 = 3.8 mm (0.1496 in) (15, Figure 25)
OSPL 800 (16, Figure 25)
OSPL 1000 (16, Figure 25)
NOTE: Refer to parts manual for our unit to determine if
these parts are installed.

26. Use a screwdriver to install OSPL 800 and 1000 spacers (If
equipped.). See Figure 76.
NOTE: Refer to parts manual for our unit to determine if
these parts are installed.

27. Install end cover. See Figure 77

29. Install six remaining bolts and tighten them. See Figure 79.
Cross tighten bolts and roll pin to 48 Nm (35 ft lb).

28. Install a washer and roll pin into hole shown in Figure 78.

30. Turn steering unit over and work from opposite side. Set
dust seal in position on housing. See Figure 80.

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31. Use a seal driver and a plastic hammer to install dust seal.
See Figure 81.

32. Install plastic plugs to prevent dirt from entering steering
unit. See Figure 82.

33. Figure 83, shows port identification for steering unit.
L = Left pressure port.
R = Right pressure port
T = Tank port
P = Pressure from pump.