Komatsu WA380-6 Operation & Maintenance Manual page 234

OPERATION OPERATION
Problem
Steering
Steering wheel is heavy
Steering wheel is loose
Parking brake
Braking effect is poor
Brake drags or remains applied
Hydraulic system
Lack of lifting power for bucket
Bucket takes time to rise
Excessive bubbles in oil
Hydraulic pressure is low
Movement of cylinder is irregular
Main causes
Lack of oil in hydraulic tank
Play in steering cylinder pin
Lack of oil in hydraulic tank
Disc is worn
Lack of oil in transmission case
Screen is clogged
Lack of oil in hydraulic tank
Clogged hydraulic tank filter
Low quality oil being used
Lack of oil in hydraulic tank
Air in oil line
Lack of oil in hydraulic tank
causes pump to suck in air
Lack of oil in hydraulic tank
TROUBLESHOOTING TROUBLESHOOTING
Remedy
Add oil to specified level. See
EVERY 100 HOURS SERVICE
Grease bearing or replace pin
and bushing where there is
play
Add oil to specified level. See
EVERY 100 HOURS SERVICE
( Replace disc)
Add oil to specified level. See
WHEN REQUIRED
( Disassemble and clean)
Add oil to specified level. See
EVERY 100 HOURS SERVICE
Replace filter. See EVERY 2000
HOURS SERVICE
Replace with good quality oil
Add oil to specified level. See
EVERY 100 HOURS SERVICE
Bleed air. See EVERY 2000
HOURS SERVICE
Add oil to specified level. See
EVERY 100 HOURS SERVICE
Then bleed air. See EVERY
2000 HOURS SERVICE
Add oil to specified level. See
EVERY 100 HOURS SERVICE
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