Komatsu 830E, Shop Manual

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L05026 Steering Component Repair L5-5
7. Hold bladder valve stem on the flats with a
wrench and tighten nut (5) securely.
8. If removed, install pressure switch (15), valve
assembly (11) and charging valve onto gas
valve manifold (14). Install new O-Ring (16) on
gas valve manifold (14). Hold bladder valve
stem with wrench and install gas valve manifold
(14) and tighten securely.
9. Holding the hydraulic port assembly (2) by the
threaded end, insert the poppet end into the
shell fluid port. Lay complete assembly in side
shell.
10. Fold anti-extrusion ring (3) to enable insertion
into the shell. Once the anti-extrusion ring has
cleared the fluid port opening, place the anti-
extrusion ring on the hydraulic port assembly
with the steel collar facing toward the shell fluid
port.
11. Pull the threaded end of the port assembly
through the shell fluid port until it seats solidly
into position on the shell fluid port opening.
12. Connect nitrogen charging kit to charging valve.
With hydraulic port assembly firmly in place,
slowly pressurize the bladder using dry nitrogen
with sufficient pressure (approximately 40-50
psi) to hold port assembly in place so both
hands are free to continue with assembly.
13. Install the metal O-Ring backup washer (6) over
hydraulic port assembly and push into the shell
fluid port to bottom it out on anti-extrusion ring.
14. Install O-ring (7) over hydraulic port assembly
and push it into the shell fluid port until it has
bottomed out against the metal O-Ring backup
washer (6).
Do not twist O-ring.
15. Install O-ring back-up (8) over hydraulic port
assembly an push until it bottoms against O-
ring
16. Insert spacer (9) with the smaller diameter of the
shoulder facing the accumulator shell.
17. Install the locking ring (10) on the hydraulic port
assembly and tighten securely. This will
squeeze the O-ring into position. Use appropri-
ate wrench on flats on port assembly to insure
the unit does not turn.
18. Install bleeder plug (12) into the hydraulic port
assembly.
19. Precharge accumulator to 100 - 120 psi (690 -
827 kPa). Refer to “Steering Accumulator
Charging Procedure” for details. After precharg-
ing, install plastic cover over hydraulic port to
prevent contamination. Do not use a screw-in
type plug.
Always store bladder accumulators with 100 -
120 psi (690 - 827 kPa) nitrogen precharge pres-
sure. Do not exceed 120 psi (827 kPa). Storing
accumulators with more than 120 psi (827 kPa)
pressure is not safe in case of leaks.
NOTE: Bladder accumulators should be stored with
100 - 120 psi (690 - 827 kPa) precharge, which fully
expands the bladder, and holds oil against the inner
walls for lubrication and to prevent rust formation.
TESTING
To carry out the testing required, it will be necessary
to check for internal and external leaks at high pres-
sure. A source of 3500 psi (24132 kPa) hydraulic
pressure and nitrogen pressure of 1400 psi (9653
kPa) will be required. A small water tank will be nec-
essary for a portion of the test.
1. Remove charging valve guard and charging
valve cap.
2. Close bleed valve.
3. Attach gauging assembly to charging valve and
tighten swivel nut (10-15 in.lb) (11.5 -17 cm kg).
4. Hold valve body (6, Figure 5-6) with one wrench
while unscrewing swivel nut (4) with a second
wrench. This will open the poppet inside the
gas valve.
Note: Four turns will fully open poppet.
5. SLOWLY charge accumulator to 100 psi (690
kPa). After 100 psi is obtained, charging rate
can be increased until fully charged at 1400 psi.
6. Tighten swivel nut (4) to close internal poppet
(10-15 in. lb.) (11.5 -17 cm kg).
7. Submerge accumulator assembly under water
and observe for 20 minutes. No leakage (bub-
bles) is permitted. If leakage is present, go to
Step 14.
8. Hold charging valve (6) with a wrench and
remove swivel nut assembly.
9. Replace cap on charging valve (10-15 in. lb.)
(11.5-17 cm kg) and install gas valve guard.