Mitsubishi Montero (1991+). Manual - part 11

A/C COMPRESSOR OIL CHECKING 



1991 Mitsubishi Montero

         1991 GENERAL SERVICING

         Compressor Refrigerant Oil Checking

         ISOLATING COMPRESSOR

NOTE:    Only compressors with stem-type service valves can be

         isolated.

         1) Connect service gauge set to the compressor service valves

and open compressor valves slightly (turn in clockwise). Start engine

and operate air conditioning. Slowly turn compressor suction valve

clockwise toward closed (front-seated) position.

         2) When suction pressure is reduced to zero or less, turn off

engine and compressor and quickly turn suction valve stem in to full

front-seated position. Suction pressure should be slightly above zero.

Turn discharge valve into front-seated position.

         3) To check oil level, slowly open compressor crankcase plug

to relieve any remaining pressure. After oil level is corrected, cap

service gauge ports on both valves. Back-seat suction service valve to

allow refrigerant to enter compressor. Open discharge valve halfway.

         4) Loosen discharge service valve cap, allowing refrigerant

pressure to force air out of compressor. Back-seat service valve and

tighten cap. Compressor is now ready for operation.

         REFRIGERANT OIL

         Only new, pure, moisture-free refrigerant oil should be used

in the air conditioning system. This oil is highly refined and

dehydrated to a point where moisture content is less than 10 parts per

million. The oil container must be tightly closed at all times when

not in use, or moisture will be absorbed into the refrigerant oil from

the air.

         SERVICING PRECAUTIONS

NOTE:    Recent findings by the EPA indicate that refrigerant is

         harmful to the earth’s protective Ozone layer. When

         discharging refrigerant, DO NOT allow refrigerant to enter

         the atmosphere. If available, use refrigerant

         recovery/recycle systems when discharging system. Always

         follow manufacturer’s instructions.

         DISCHARGING SYSTEM PRECAUTIONS

         If compressor has stem-type service valves, it can be

isolated and removed without discharging entire system. See ISOLATING

COMPRESSOR at the beginning of this article. Otherwise, discharge

system completely before loosening any fittings.

         DISCONNECTING LINES & FITTINGS TEST

         After system is discharged, carefully clean area around all

fittings to be opened. Always use 2 wrenches when tightening or

loosening fittings to avoid twisting or distorting lines. Cap or plug

all openings as soon as lines are removed. DO NOT remove caps until

immediately before connections are made. This will keep entry of air

and moisture to a minimum.

         CONNECTING LINES AND FITTINGS

         A new gasket or "O" ring should be used in all instances when

connecting lines or fittings. Dip "O" ring in new refrigerant oil and

ensure it is not twisted during installation. Always use 2 wrenches to

prevent damage to lines and fittings.

         PLACING SYSTEM IN OPERATION

         After component service or replacement has been completed and

all connections have been made, evacuate system thoroughly with a

vacuum pump. Charge system with proper amount of refrigerant and

perform a leak test. See REFRIGERANT OIL & R-12 SPECIFICATIONS chart

in this section for system capacities. Be sure to check all fittings

that have been opened. After system has been leak tested, make a

system performance check.

NOTE:    Air conditioning systems will not normally need addition of

         refrigerant oil unless definite oil loss has occurred due to

         ruptured lines, leaking compressor seals, compressor

         overhaul or component replacement.

         ATSUGI ROTARY VANE DRAIN & REFILL

         1) Before checking and adjusting oil level, operate

compressor at engine idling speed, with controls set for maximum

cooling and high blower speed, for 20 to 30 minutes to return oil to

compressor.

         2) Stop engine, discharge refrigerant and remove compressor

from vehicle. See SERVICING PRECAUTIONS at beginning of article. Drain

compressor oil from compressor discharge port and measure the amount.

Oil is sometimes hard to drain when compressor is cool. Remove oil

while compressor is warm.

         3) If the amount drained is less than 3 ounces, conduct leak

tests at system connections, and if necessary, repair or replace

faulty parts. Check purity of oil and adjust oil level as follows.

         4) If amount drained was above 3 ounces, oil level is right.

Pour in same amount as was drained. If amount drained was below 3

ounces, pour in 3 ounces of new refrigerant oil.

         BOSCH 6-CYL DRAIN & REFILL

         1) Before checking and adjusting oil level, operate

compressor at engine idling speed, with controls set for maximum

cooling and high blower speed, for 20 to 30 minutes to return oil to

compressor.

         2) Stop engine and discharge refrigerant. Remove refrigerant

oil level inspection plug on side of compressor. Oil should be at

lower lip of threaded hole. Add necessary new refrigerant oil (if

low). Replace inspection plug and tighten to 10-12 ft. lbs. (14-16 N.

m).

         CALSONIC V5 5-CYLINDER

         1) Before checking and adjusting oil level, operate

compressor at 1000-1500 engine RPM, and set controls at maximum

cooling and blowing speed for 20-30 minutes to return oil to

compressor.

         2) Stop engine. Discharge refrigerant and remove compressor

from vehicle. See SERVICING PRECAUTIONS at the beginning of this

article. Drain compressor oil from compressor discharge port and

measure oil amount. Oil may be hard to drain if compressor is cool.

Drain oil while compressor is warm.

         3) If amount drained is less than 3.2 ounces, conduct leak

tests at system connections. Repair or replace faulty parts as

necessary. Check purity of oil and oil level as follows.

         4) If amount drained is more than 3.2 ounces, oil level is

okay; fill with same amount drained using new oil. If amount drained

is less than 3.2 ounces, pour in 3.2 ounces of new refrigerant oil.

         DIESEL KIKI ROTARY VANE DRAIN & REFILL

         1) Before checking and adjusting oil level, operate

compressor at engine idling speed, with controls set for maximum

cooling and high blower speed, for 20 to 30 minutes to return oil to

compressor.

         2) Stop engine, discharge refrigerant and remove compressor

from vehicle. See SERVICING PRECAUTIONS at the beginning of this

article. Drain compressor oil from compressor discharge port and

measure the amount. Oil is sometimes hard to drain when compressor is

cool. Remove oil while compressor is warm.

         3) If the amount is less than 2.4 ounces, conduct leak tests

at system connections, and if necessary, repair or replace faulty

parts. Check purity of oil and adjust oil level as follows.

         4) If amount drained was above 2.4 ounces, oil level is

right. Pour in same amount as was drained. If amount drained was below

2.4 ounces, pour in 2.4 ounces of new refrigerant oil.

         DIESEL KIKI 6-CYL DRAIN & REFILL

         1) Before checking and adjusting oil level, operate

compressor at engine idling speed, with controls set for maximum

cooling and high blower speed, for 20 to 30 minutes to return oil to

compressor.

         2) Stop engine, discharge refrigerant and remove compressor

from vehicle. See SERVICING PRECAUTIONS at the beginning of this

article. Remove oil drain plug and drain oil. Measure amount of oil

drained. Install drain plug with new "O" ring.

         3) If amount drained was more than 2 ounces (4.4 ounces for

Infinity), refill with same amount of new oil. If amount drained was

less than 2 ounces (4.4 ounces for Infinity), refill with 2 ounces (4.

4 ounces for Infinity). Install filler plug and recharge system.

         FORD FX-15 6-CYLINDER DRAIN & REFILL

NOTE:    Replacement FX-15 compressors contain 7 ounces of refrigerant

         oil. Prior to installing compressor, drain refrigerant oil

         and determine proper amount of refrigerant oil to be added.

         1) Slowly discharge system. Remove A/C compressor. Drain

compressor oil from suction and discharge ports. Measure amount

drained and discard oil.

         2) If amount drained from removed (old) compressor is between

3 and 5 ounces, add drained amount of new SUNINSO 5GS refrigerant oil

into the NEW compressor through suction port.

         3) If amount drained is less than 3 ounces, add 3 ounces to

the NEW compressor. If amount drained is more than 5 ounces, add

5 ounces. Use new "O" rings on refrigerant lines. Install A/C

compressor. Evacuate and recharge system. Perform leak test.

         HARRISON 4-CYL DRAIN & REFILL

NOTE:    The Harrison compressor DOES NOT have an oil sump. It’s

         crucial that the compressor remains well oiled. It takes

         very little time to destroy this compressor if it runs dry.

         The Harrison 4-cyl compressor is charged (new) with 6 ounces

of refrigerant oil. Because compressor does not have an oil sump, it

should not have to be removed for oil measurement (it retains very

little oil). Note the following situations for checking and adding oil

to this compressor.

         NO OIL LEAK; REPLACING COMPONENTS

         If only the compressor is to be replaced, remove, drain oil,

measure and reinstall an equal amount of new oil. If evaporator is

being replaced, add 3 ounces of new oil. If condenser is being

replaced, add one ounce.

         LOSS OF REFRIGERANT OVER EXTENDED PERIOD

         When a loss of refrigerant has occurred over an extended

period of time and a component is being replaced to correct the leak,

add an appropriate amount of refrigerant oil to the component.

         SIGNS OF EXCESSIVE OIL LEAKAGE

         If system has lost excessive oil, remove accumulator. Drain

and measure oil. If more than 3 ounces is measured, replace the same

amount of new oil as was drained. If less than 3 ounces is measured,

add 3 ounces of new oil. Add and additional 2 ounces of new oil to

compensate for that lost by replacing the accumulator (held in

desiccant).

NOTE:    If the exact oil charge is in doubt, drain and flush system.

         Add a new 6-ounce charge of refrigerant oil to the system.

         HARRISON V5 5-CYLINDER DRAIN & REFILL

         1) If system is operable, run for several minutes to

stabilize system before performing repairs. Turn off engine. Discharge

system and remove compressor. See SERVICING PRECAUTIONS at the

beginning of this article. Remove drain plug. Drain and measure oil.

         2) If more than one ounce is drained, add same amount. If

less than one ounce is drained, add 2 ounces of new refrigerant oil to

compressor.

         3) If A/C components are replaced, add refrigerant oil to

system. Add one ounce if condenser is replaced. Add 3.5 ounces if

accumulator is replaced.

         4) When replacing a component which has caused a large

refrigerant leak, add 3 ounces of new oil plus the required amount for

the part being replaced. Add oil directly to part being replaced if

possible. If oil can not be easily added to part, add oil to

accumulator.

NOTE:    If oil drained contains metal chips or other debris, replace

         receiver-drier. Flush out system before evacuating and

         recharging.