Komatsu PC58UU-3 - Page 79

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD CONTROL VALVE
10-36
PC58UU-3
Unit: mm
No. Check item Criteria
Remedy
A
Spool return spring
(travel, boom, arm, offset,
swing)
Standard size Repair limit
Replace
spring if any
damages or
deformations
are found
Free length
x O.D.
Installed
length
Installed
load
Free length
Installed
load
29.0 x 17.5 28.5
22.6 N
{2.30 kg}
—
18.0 N
{1.84 kg}
B
Spool return spring
(bucket)
29.15 x 17.5 28.5
22.6 N
{2.30 kg}
—
18.0 N
{1.84 kg}
C
Spool return spring
(blade)
42.0 x 20.0 25.4
74.53 N
{7.60 kg}
—
59.62 N
{6.08 kg}
D Unload valve spring 27.2 x 12.5 20.5
55.41 N
{5.65 kg}
—
44.33 N
{4.52 kg}
E Boom assist valve spring 33.77 x 17.5 28.5
120.92 N
{12.33 kg}
—
96.69 N
{9.86 kg}
F
Pressure compensation
valve spring
20.0 x 8.40 12.0
6.86 N
{0.70 kg}
—
5.49 N
{0.56 kg}
G
Pressure compensation
valve spring
22.75 x 8.40 17.0
16.57 N
{1.69 kg}
—
13.24 N
{1.35 kg}
H
Pressure compensation
valve spring
21.55 x 8.40 17.0
8.34 N
{0.85 kg}
—
6.67 N
{0.68 kg}
J
Pressure compensation
valve spring
22.36 x 8.40 17.0
9.81 N
{1.0 kg}
—
7.85 N
{0.8 kg}
K
Pump merge-divider valve
spring
41.1 x 13.8 22.0
44.33 N
{4.52 kg}
—
35.50 N
{3.62 kg}
L Lift check valve spring 29.0 x 13.3 21.0
15.30 N
{1.56 kg}
—
12.26 N
{1.25 kg}
M Cooler bypass valve spring 27.2 x 13.2 21.0
78.85 N
{8.04}
—
63.06 N
{6.43 kg}
N Check valve spring 13.0 x 6.50 9.0
2.26 N
{0.23 kg}
—
1.77 N
{0.18 kg}
P
Check valve spring
(arm, bucket, blade)
21.9 x 5.0 15.8
1.96 N
{0.20 kg}
—
1.57 N
{0.16 kg}
Q
Check valve spring
(boom)
21.9 x 5.0 15.8
1.96 N
{0.20 kg}
—
1.57 N
{0.16 kg}
R
Check valve spring
(boom)
16.4 x 7.50 9.90
2.26 N
{0.23}
—
1.77 N
{0.18 kg}