Komatsu 830E-AC, Shop Manual

Page: 946 / 1085

N4-20 Operator Comfort 10/06 N04031
SYSTEM OIL
R-134a air conditioning systems require the use of
Polyalkylene Glycol (PAG) lubricating oil. This is the
only oil recommended for use in this system. The
Komatsu PAG oil (p/n PC2212) is the oil that is fur-
nished in the system on Komatsu trucks.
Handling and Reusing PAG Oil
• Avoid skin contact and inhalation of PAG oil, as
these are normal precautions with any chemical.
• PAG oil removed from new or old components
must not be retained for re-use. It must be stored
in a marked container and properly sealed. PAG
oil is an environmental pollutant and must be
properly disposed of after use.
• PAG oil in containers or in an air conditioning
system must not be left exposed to the
atmosphere any longer than necessary. PAG oil
absorbs moisture very rapidly, and therefore, any
absorbed moisture could cause damage to an air
conditioning system.
Oil Quantity
It is critical to keep the correct amount of lubricant in
the air conditioning system at all times. Failure to do
so could result in damage to the compressor.
Damage to the compressor can be a result from not
only a lack of oil, but from too much oil, also. A lack
of oil will cause excess friction and wear on moving
parts. Excessive oil can result in “slugging” the com-
pressor. This condition occurs when the compressor
attempts to compress liquid oil as opposed to vapor-
ized refrigerant. Since liquid cannot be compressed,
damage to internal parts results.
Checking System Oil
The receiver-drier and accumulator must be
replaced each time the system is opened.
1. Remove the compressor from the truck. With
the compressor positioned horizontally, remove
the drain plug, and capture the oil in a clear
graduated container. Rock the compressor
back and forth, and rotate the shaft to facilitate
oil removal.
Under no circumstances should the A/C com-
pressor be stood upright onto the clutch assem-
bly. Damage to the compressor clutch will result,
leading to premature compressor failures.
2. Inspect the oil for any foreign particles. If parti-
cles are found, further investigation and service
are necessary to determine the source. After
repair, the system will need to be flushed. Refer
to System Flushing. If no particles are found,
proceed to the next step.
3. Add 207 ml (7oz.) of PAG oil to the compressor
sump. Add the oil through the drain port, and
install the drain plug. It is important to only add
the specified amount to ensure optimal system
performance. Too much oil will result in a reduc-
tion in cooling. Too little oil will result in com-
pressor failure.
4. Determine the correct amount of additional oil
to add to the system by using the Replacing Oil
table. Add this extra oil to the inlet side of the
receiver drier or accumulator.
NOTE: If truck is being assembled for the first time,
add 207 ml (7oz.) of PAG oil to the inlet side of the
receiver-drier or to the accumulator.
EXAMPLE - If only the accumulator and receiver
drier were replaced, then add 120 ml (4 oz.) of PAG
oil to the inlet side of the receiver-drier or to the accu-
mulator. If the evaporator was also replaced at this
time, then add 150 ml (5 oz.) of PAG oil to the inlet
side of the receiver-drier or to the accumulator.
NOTE: The proper quantity of oil may be injected into
the system during charging as an alternate method of
adding oil.