Speed Or Power Of Bucket Is Low - Komatsu PC130-7 Shop Manual

TROUBLESHOOTING
H-9 Speed or power of bucket is low
Trouble

• Speed or power of bucket is low.

Related
• Carry out the troubleshooting in working mode A.
information
Malfunction of right PPC
1
valve (bucket circuit)
Malfunction of bucket con-
2
trol valve (spool)
Possible causes
Malfunction of bucket con-
and standard
3 trol valve (pressure com-
value in normal
pensation valve)
state
Malfunction or defective
4 seal of bucket control valve
(suction valve)
Malfunction or defective
5 seal of centralized safety-
suction valve
Malfunction of bucket cylin-
6
der (cylinder unit)
20-512
(1)
Cause Standard value in normal state/Remarks on troubleshooting
aPrepare with engine stopped, then run engine at high idling and carry
out troubleshooting.
Right work equipment control lever
Bucket CURL position
Bucket DUMP position
The spool of the bucket control valve may have a malfunction. Check it
directly.
The pressure compensation valve of the bucket control valve may have
a malfunction. Check it directly.
The suction valve of the bucket control valve may have a malfunction or
a defective seal. Check it directly.
The centralized safety-suction valve may have a malfunction or a defec-
tive seal. Check it directly.
(A trouble of the centralized safety-suction valve have bad effects on the
boom and arm.)
aPrepare with engine stopped, then run engine at high idling and carry
out troubleshooting.
Relieved in CURL position
Neutral position
Bucket cylinder
PPC valve output pressure
0 MPa
2
{0 kg/cm }
2.84 – 3.43 MPa
2
{29 – 35 kg/cm }
Leakage from cylinder
15 cc/min
PC130-7
H-9