Checking The Engine Speed - Komatsu PC20R-8 Shop Manual

TESTING AND ADJUSTMENTS

CHECKING THE ENGINE SPEED

When checking the engine rpm , always be very
careful not to touch parts that reach high tempera-
tures and not to get entangled in rotating elements.
H Check the engine speed after the following conditions
have been reached:
Temperature of engine cooling water: 68 ± 80 ëC.
.
Temperature of hydraulic oil: 45 ± 55 ëC.
.
1 - Mount and connect the tachometer C1.
H If the stroboscopic tachometer C2 is used, make a
distinct mark on the engine pulley to facilitate the
reading.
2 - Start the engine and check:
Low idling without load (accelerator lever in "mini-
.
mum" position).
High idling without load (accelerator lever in
.
"maximum" position).
H Low idling:
PC20R-8: 950w25 rpm
PC27R-8: 1050w25 rpm
H High idling:
PC20R-8: 2780w25 rpm
PC27R-8: 2785w25 rpm
H If the minimum and maximum speeds do not fall
within permissible limits when the engine is with-
out load, check the position locks of the accelera-
tor lever, and the sheathing of the accelerator
well, before carrying out any tests under load.
(See «ADJUSTMENT OF THE ACCELERATOR
LEVER»).
. Engine rpm with the pumps under load.
H Boom at max. pressure:
PC20R-8: 2740w50 rpm
PC27R-8: 2650w50 rpm
H Boom and swing at max. pressure:
PC20R-8: 2720w50 rpm
PC27R-8: 2625w50 rpm
H If engine efficiency does not fall within permissi-
ble limits, have the engine checked by an
authorised workshop.
PC20R-8 PC27R-8
CHECKING THE ENGINE SPEED
1
C
MAX
MIN
RKPA2230
RKPB5490
20-25