Air Circuit Diagram - Komatsu PC1250 -8 Shop Manual

00 Index and foreword
2. Preparations for work
1) Before adding oil or making any repairs,
park the machine on a hard and level
ground, and apply the parking brake and
block the wheels or tracks to prevent the
machine from moving.
2) Before starting work, lower the work
equipment (blade, ripper, bucket, etc.) to
the ground. If this is not possible, insert
the lock pin or use blocks to prevent the
work equipment from falling. In addition,
be sure to lock all the control levers and
hang warning signs on them.
3) When disassembling or assembling, sup-
port the machine with blocks, jacks, or
stands before starting work.
4) Remove all mud and oil from the steps or
other places used to get on and off the
machine. Always use the handrails, lad-
ders or steps when getting on or off the
m a c h i n e . N e v e r j u m p o n o r o ff t h e
machine. If it is impossible to use the
handrails, ladders or steps, use a stand to
provide safe footing.
3. Precautions during work
1) Before disconnecting or removing compo-
nents of the oil, water, or air circuits, first
release the pressure completely from the
circuit. When removing the oil filler cap, a
drain plug, or an oil pressure pickup plug,
loosen it slowly to prevent the oil from
spurting out.
2) The coolant and oil in the circuits are hot
when the engine is stopped, so be careful
not to get scalded. Wait for the oil and
coolant to cool before carrying out any
work on the oil or water circuits.
3) Before starting work, stop the engine.
When working on or around a rotating
part, in particular, stop the engine. When
checking the machine without stopping
the engine (measuring oil pressure,
revolving speed, temperature, etc.), take
extreme care not to get rolled or caught in
rotating parts or moving parts.
4) For the machine equipped with a bat-
tery disconnct switch, turn the battery
disconnect switch to the OFF (O) posi-
tion and pull the switch key out, before
starting the work. For machines without
a battery disconnct switch, remove the
cable from the battery , before starting the
work. Always remove the cable from the
negative (-) terminal first.
PC1250-8
5) When raising a heavy component (heavier
than 25 kg), use a hoist or crane. Before
starting work, check that the slings (wire
ropes, chains, and hooks) are free from
damage. Always use slings which have
ample capacity and install them to proper
places. Operate the hoist or crane slowly
to prevent the component from hitting any
other part. Do not work with any part still
raised by the hoist or crane.
6) When removing a cover which is under
internal pressure or under pressure from a
spring, always leave 2 bolts in diagonal
positions. Loosen those bolts gradually
and alternately to release the pressure,
and then remove the cover.
7) When removing components, be careful
not to break or damage the electrical wir-
ing. Damaged wiring may cause electrical
fires.
8) When removing piping, stop the fuel or oil
from spilling out. If any fuel or oil drips
onto the floor, wipe it up immediately. Fuel
or oil on the floor can cause you to slip
and can even start fires.
9) As a general rule, do not use gasoline to
wash parts. Do not use it to clean electri-
cal parts, in particular.
10) Be sure to assemble all parts again in their
original places. Replace any damaged
parts and parts which must not be reused
with new parts. When installing hoses and
wires, be sure that they will not be dam-
aged by contact with other parts when the
machine is operated.
11) When installing high pressure hoses,
make sure that they are not twisted. Dam-
a g e d t u b e s a r e d a n g e r o u s , s o b e
extremely careful when installing tubes for
high pressure circuits. In addition, check
t h a t c o n n e c t i n g pa r ts a r e c o r r e c t l y
installed.
SEN00892-04
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