all been designed with unique fittings to ensure that
an R-134a system is not accidentally contaminated
with the wrong refrigerant (R-12). There are also
labels posted in the engine compartment of the vehi-
cle and on the compressor identifying to service tech-
nicians that the air conditioning system is equipped
with R-134a.
REFRIGERANT OIL
DESCRIPTION
The refrigerant oil used in R-134a refrigerant sys-
tems is a synthetic-based, PolyAlkylene Glycol (PAG),
wax-free lubricant. Mineral-based R-12 refrigerant
oils are not compatible with PAG oils, and should
never be introduced to an R-134a refrigerant system.
There are different PAG oils available, and each
contains a different additive package. The A/C com-
pressors for this vehicle are designed to use an ND-8
PAG refrigerant oil. Use only the refrigerant oil of
this type to service the refrigerant system.
OPERATION
After performing any refrigerant recovery or recy-
cling operation, always replenish the refrigerant sys-
tem with the same amount of the recommended
refrigerant oil as was removed. Too little refrigerant
oil can cause compressor damage, and too much can
reduce air conditioning system performance.
PAG refrigerant oil is much more hygroscopic than
mineral oil, and will absorb any moisture it comes
into contact with, even moisture in the air. The PAG
oil container should always be kept tightly capped
until it is ready to be used. After use, recap the oil
container immediately to prevent moisture contami-
nation.
STANDARD PROCEDURE
REFRIGERANT OIL LEVEL
When an A/C system is assembled at the factory,
all components except the compressor are refrigerant
oil free. After the refrigerant system has been
charged and operated, the refrigerant oil in the com-
pressor is dispersed throughout the refrigerant sys-
tem. The receiver-drier, evaporator, condenser, and
compressor will each retain a significant amount of
the needed refrigerant oil.
It is important to have the correct amount of oil in
the refrigerant system. This ensures proper lubrica-
tion of the A/C compressor. Too little oil will result in
damage to the A/C compressor. Too much oil will
reduce the cooling capacity of the A/C system.
It will not be necessary to check the oil level in the
A/C compressor or to add oil, unless there has been
an oil loss. An oil loss may occur due to a rupture or
leak from a refrigerant line, a connector fitting, a
component, or a component seal. If a leak occurs, add
30 milliliters (1 fluid ounce) of refrigerant oil to the
refrigerant system after the repair has been made.
Refrigerant oil loss will be evident at the leak point
by the presence of a wet, shiny surface around the
leak.
Refrigerant oil must be added when a receiver/
drier, A/C evaporator, or A/C condenser are replaced.
See the Refrigerant Oil Capacities chart. When an
A/C compressor is replaced, the refrigerant oil must
be drained from the old compressor and measured.
Drain all of the refrigerant oil from the new compres-
sor, then fill the new compressor with the same
amount of refrigerant oil that was drained out of the
old compressor.
REFRIGERANT OIL CAPACITIES
Component
ml
fl oz
Total A/C System Fill
410
13.9
Receiver/Drier
30
1.0
A/C Condenser
30
1.0
A/C Evaporator
60
2.0
A/C Compressor
Drain and measure the oil
from the old compressor -
see text.
SUCTION LINE
REMOVAL
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-
tions could result in possible personal injury or
death.
(1) Recover the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM RECOVERY)
(2) Disconnect and isolate the negative battery
cable.
(3) Remove the routing clip retaining nut and dis-
engage the metal routing clip from the A/C suction
line.
(4) Disengage the plastic routing clip located near
the A/C expansion valve from the A/C suction line.
(5) Remove the nut that secures the A/C suction
and liquid lines to the stud on the A/C expansion
valve (Fig. 19).
VA
PLUMBING
24 - 81