Komatsu PC20R-8 Shop Manual page 117

TESTING AND ADJUSTMENTS
Normal or standard technical data . . . . .. . . . . .. . . . .. . . 2
Special tools . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . 24
Checking the engine speed . .. . . . . .. . . . .. . . . . .. . . . .. . 25
Adjustment of valve clearance . . . . .. . . . .. . . . . .. . . . .. . 26
Normal or standard tech . . . . .. . . . . .. . . . .. . . . . .. . . . .. . 26
Measurement of the compression pressure .. . . . .. . 27
Control and adjustment of the tension
of the fan belt .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . 28
Control and adjustment of the injection timing . . .. . 29
Control and adjustment of the accelerator stroke . . 31
Adjustment of the stroke of the
blade command lever. . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . 32
Adjusting the flexible cables .. . . . . .. . . . .. . . . . .. . . . .. . 33
Control and adjustment of the stroke of the
travel lever . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . 34
Adjustment of the stroke of
the boom swing command pedal . .. . . . .. . . . . .. . . . .. . 35
Adjustment of the ppc valve clearances . . . . .. . . . .. . 36
Adjustment of the rubber pad and safety
microswitch for servo-control engagement . .. . . . .. . 37
Control and adjustment of
the track-shoe tension . . .. . . . .. . . . . .. . . . .. . . . . .. . . . .. . 38
When carrying out controls, adjustments or analyses for troubleshooting, park the machine on firm, level
ground. Apply all the machine safety devices and use blocks to prevent any machine movement.
When more than one person is engaged in the work, use the prescribed notices that indicate that the machine
is undergoing maintenance. Do not allow any unauthorised persons to remain in the vicinity.
When checking the level of the cooling liquid, wait until this liquid has cooled. If the radiator cap is removed
while the liquid is still hot and under pressure, it may cause severe burns.
Take great care not to get entangled in moving parts (fan, alternator belt or any of the rotating elements).
PC20R-8 PC27R-8
Control and regulation of the pressures in the
hydraulic circuits .. . . . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 39
Control and regulation of the ls differential pressure
and adjustment of the LS valve (PC20R-8) . . . . .. . . . 44
Regulation of the PC valve (PC20R-8) . . . . .. . . . .. . . . 46
Control and regulation of the ls differential pressure
and adjustment of the LS valve (PC27R-8) . . . . .. . . . 47
Regulation of the PC valve (PC27R-8) . . . . .. . . . .. . . . 49
Control and regulation of the servo-control
power supply . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 50
Elimination of residual pressures - pressurisation
of the tank . .. . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 51
Bleeding air from the hydraulic circuits . . . .. . . . .. . . . 52
Control of hydraulic drifts - analysis of the causes
of a drift . . . . .. . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 54
Checking for any leakages inside the working
equipment cylinders. . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 60
Checking for any leakages inside
the swing motor . .. . . . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 61
Methods for testing for leakages inside the
swivel joint . .. . . . . .. . . . .. . . . . .. . . . .. . . . . .. . . . . .. . . . .. . . . 62
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