Komatsu ecot3 PC300-8, Shop Manual

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10 Structure, function and maintenance standard SEN01994-01
PC300, 350-8
11
1. Return spring
2. Merge-divide valve (for LS)
3. Valve (Sequence valve)
4. Spring (Sequence valve)
5. Merge-divide valve (Main)
6. Return spring
Boom valve
7. Drift prevention valve
8. LS shuttle valve
9. Pressure compensation valve (Lower)
10. Spool
11. 2-stage safety-suction valve (Lower)
12. Regeneration circuit check valve
13. Suction valve (Raise)
14. Pressure compensation valve (Raise)
L.H. travel valve
15. Merge-divider valve (travel junction valve)
16. Return spring
17. LS shuttle valve
18. Pressure compensation valve (Forward)
19. Spool
20. Suction valve (Forward)
21. Suction valve (Reverse)
22. Pressure compensation valve (Reverse)
Bucket valve
23. LS shuttle valve
24. Pressure compensation valve (Curl)
25. Spool
26. Safety-suction valve (Curl)
27. Safety-suction valve (Dump)
28. Pressure compensation valve (Dump)
Unit: mm
No. Check item Criteria Remedy
29
Spool return spring
Standard size Repair limit
If damaged or
deformed, replace
spring.
Free length x
Outside diameter
Installed
length
Installed
load
Free length
Installed
load
46.6 x 21.8 33.0
157 N
{16.0 kg}
—
126 N
{12.8 kg}
30
Check valve spring 70.9 x 18.0 56.0
250 N
{25.5 kg}
—
200 N
{20.4 kg}
31
Spool return spring 64.5 x 32.3 63.0
178 N
{18.1 kg}
—
142 N
{14.5 kg}
32
Check valve spring 33.0 x 12.0 26.0
35.3 N
{3.6 kg}
—
28.2 N
{2.88 kg}
33
Check valve spring 16.4 x 8.9 11.5
13.7 N
{1.4 kg}
—
11.0 N
{1.12 kg}
34
Check valve spring 31.5 x 10.3 19.5
5.9 N
{0.6 kg}
—
4.71 N
{0.48 kg}
35
Piston return spring 30.7 x 20.5 23.0
50.0 N
{5.1 kg}
—
40.0 N
{4.08 kg}