Komatsu PC20R-8 Shop Manual page 169

TESTING AND ADJUSTMENTS
2. Bleeding air from the cylinders
1 - Start the engine and let it run at low idling for
about 5 minutes.
2 - Lower and raise the boom 4-5 times.
H Lower and raise the piston of the boom up to
about 100 mm of the end of its stroke.
Every care must be taken to avoid pressuris-
ing the circuits.
3 - Bring the engine up to high idling and repeat the
operations described in point 2. Return the engine
to low idling and pout the piston through its entire
stroke until it reaches max. pressure in both direc-
tions.
4 - Repeat the operation (starting from point 2) for the
arm, bucket, arm swing, and blade cylinders.
3. Bleeding air from the swing motor
Make sure that the swing-locking pin is not en-
gaged.
1 - With the engine at low idling, rotate the revolving
frame three turns towards the left.
2 - Repeat the same manoeuvre, rotating the revol-
ving frame to the right.
4. Bleeding air from the travel motors
1 - With the engine at low idling, use the working
equipment to raise the left-hand track-shoe from
the ground.
2 - Let the track-shoe turn for about 30 seconds.
3 - Repeat points 1 and 2 for the right-hand track-
shoe.
H Engage the travel increment for about 10 sec-
onds.
5. Bleeding air from any optional equipment
H This method must be used for all the optional
working equipment, unless otherwise indi-
cated.
1 - Each time an item of optional working equipment
is installed, operate the equipment repeatedly,
with the engine at low idling, until all air has been
completely eliminated.
PC20R-8 PC27R-8
BLEEDING AIR FROM THE HYDRAULIC CIRCUITS
BOOM CYLINDER
3 Turns
3 Giri
3 Turns
3 Giri
100 ± 150 mm
100 ÷ 150 mm
RKP04940
RKP04700
RKP04690
20-53