Mitsubishi Montero (1998+). Manual - part 26

A/C SYSTEM GENERAL SERVICING 

1998 Mitsubishi Montero

         1998 AIR CONDITIONING & HEAT

         Mitsubishi - A/C System General Servicing

         Diamante, Eclipse, Galant, Mirage, Montero, Montero Sport &

         3000GT

         A/C COMPRESSOR APPLICATIONS

A/C COMPRESSOR APPLICATION TABLE

Application                                       Compressor

Diamante  .........................  Sanden MSC105CVS Scroll

Eclipse

  2.0L Non-Turbo  .............  Nippondenso 10PA17C 10-Cyl.

  2.0L Turbo & 2.4L  ..............  Sanden MSC105CVS Scroll

Galant  ............................  Sanden MSC90C12 Scroll

Mirage  ...............................  Sanden MSC90 Scroll

Montero  .......................  Nippondenso 10PA15 10-Cyl.

Montero Sport  ......................  Sanden MSC105C Scroll

3000GT  ..............................  Sanden MSC105 Scroll

         USING R-12 & R-134a REFRIGERANT

         HANDLING/SAFETY PRECAUTIONS

         1) Always work in a well-ventilated, clean area. Avoid

breathing refrigerant vapors. Exposure may irritate eyes, nose and

throat. Refrigerant is colorless and is invisible as a gas.

Refrigerant is heavier than oxygen and will displace oxygen in a

confined area.

         2) A/C system high pressure can cause severe injury to eyes

and skin if a hose were to burst. Always wear eye protection, gloves

and other protective clothing when working around A/C system and

refrigerant.

         3) Refrigerant evaporates quickly when exposed to atmosphere,

freezing anything it contacts. If liquid refrigerant contacts eyes or

skin (frostbite), DO NOT rub eyes or skin. Immediately flush affected

area with cool water for 15 minutes and consult a doctor or hospital.

         4) Never use R-134a in combination with compressed air for

leak testing. Pressurized R-134a in the presence of oxygen (air

concentrations greater than 60 percent by volume) may form a

combustible mixture. DO NOT introduce compressed air into R-134a

containers (full or empty), A/C system components or service

equipment.

         5) DO NOT expose A/C system components to high temperatures,

steam cleaning for example, as excessive heat will cause

refrigerant/system pressure to increase. Never expose refrigerant

directly to open flame. If refrigerant needs to be warmed, place

bottom of refrigerant tank in warm water. Water temperature MUST NOT

exceed 125



F (52



C).

CAUTION: When R-134a is exposed to an open flame, drawn into engine,

         or detected with a Halide (propane) leak tester, a poisonous

         gas is formed. Keep work areas well ventilated.

         6) Use care when handling refrigerant containers. DO NOT

drop, strike, puncture or incinerate containers. Use Department Of

Transportation (DOT) approved, DOT 4BW or DOT 4BA refrigerant

containers.

         7) Never overfill refrigerant containers. The safe filling

level of a refrigerant container MUST NOT exceed 60 percent of the

container’s gross weight rating. Store refrigerant containers at

temperature less than 125



F (52



C).

         8) R-134a refrigerant is sold and stored in 30- or 50-pound

Light Blue containers, while Freon (R-12) is stored in White colored

containers.

         9) Refrigerant R-12 and R-134a must never be mixed, as they

and their desiccants and lubricants are not compatible. If

refrigerants are mixed, system cross-contamination or A/C system

component failure may occur. Always use separate servicing and

refrigerant recovery/recycling equipment.

         10) Follow equipment manufacturer instructions of all service

equipment to be used. The Material Safety Data Sheet (MSDS), provided

by refrigerant manufacturer/suppliers, contains valuable information

regarding the safe handling of refrigerants.

         11) Before connecting refrigerant lines always lubricate "O"

rings using appropriate refrigerant oil.

         12) Always plug or cap A/C system refrigerant lines and

component connections as soon as possible to protect components from

moisture and/or dust. DO NOT remove plugs or caps until ready to

install component.

         13) Always use a back-up wrench when tightening or loosening

fittings.

         IDENTIFYING R-134a SYSTEMS & COMPONENTS

         To prevent refrigerant cross-contamination, use following

methods to identify R-134a based systems and components.

         Fittings & "O" Rings

         All R-134a based A/C systems use 1/2" - 16ACME threaded

fittings (identifiable by square threads) and quick-connect service

couplings. See Fig. 1. Besides the use of these fittings, most

manufacturers will use Green colored "O" rings in R-134a systems.

Fig. 1:  Identifying R-134a Fittings & Quick-Connect Service Couplings

Courtesy of Audi of America, Inc.

         Underhood A/C Specification Labels

         Most R-134a based systems will be identified through the use

of underhood labels, or with R-134a refrigerant clearly printed on

labels. See Figs. 2 and 3. Labels may be located on underside of hood,

compressor, firewall and/or strut supports. Before servicing an A/C

system, always determine which refrigerant is being used.

Fig. 2:  Underhood A/C Specification Label (Typical)

Courtesy of Nissan Motor Co., U.S.A.

Fig. 3:  A/C Specification Labels Located On Compressor (Typical)

Courtesy of Nissan Motor Co., U.S.A.

         Other Means Of Identification

         Refrigerant R-134a, when viewed through a sight glass, may

have a "milky" appearance due to the mixture of refrigerant and

lubricating oil. As the refrigerant and oil DO NOT exhibit a "clear"

sight glass on a properly charged A/C system, most R-134a systems have

no sight glass.

         REFRIGERANT OILS

NOTE:    Use ONLY the specified oil for the appropriate system or A/C

         compressor. Always check vehicle underhood A/C specification

         label or A/C compressor label before adding refrigerant oil

         to A/C compressor/system. See Figs. 2 and 3. Always use

         refrigerant oil specified on vehicle underhood A/C

         specification label if different from the following list.

         Refrigerant R-12 based systems use mineral oil, while R-134a

systems use Polyalkylene Glycol (PAG) oils. Using a mineral oil based

lubricant with R-134a will result in A/C compressor failure due to

lack of proper lubrication. The following R-134a refrigerant oils are

currently specified:

         Use DENSO/ND-Oil 8 refrigerant oil on Nippondenso

compressors. Use SUN PAG 56 refrigerant oil on Sanden compressors.

NOTE:    PAG oils absorb moisture very rapidly, 2.3-5.6 percent by

         weight, as compared to a mineral oil absorption rate of

         0.005 percent by weight.

         SERVICE EQUIPMENT

         A/C systems using R-134a refrigerant and PAG lubricants

cannot use R-12 refrigerant or mineral oil lubricants. R-134a

refrigerant is NOT compatible or interchangeable with R-12

refrigerant. Separate sets of hoses, manifold gauge sets and

recovery/recycling equipment are required to service the different

systems. This is necessary to avoid cross-contaminating and damaging

A/C system. A single set of A/C service equipment cannot be cleaned

thoroughly enough to be used with both types of refrigerant.

         All equipment used to service A/C systems using R-134a must

be U.L. listed and certified to meet SAE standard J2210. The service

hoses on the manifold gauge set must have manual (turn wheel) or

automatic back-flow valves at the service port connector ends. This

will prevent refrigerant from being released into the atmosphere.

         For identification purposes, R-134a service hoses must have a

Black stripe along its length and be clearly labeled SAE J2196/R-134a.

The low pressure test hose is Blue with a Black stripe. The high

pressure test hose is Red with a Black stripe, and the center test

hose is Yellow with a Black stripe.

         R-134a manifold gauge sets can be identified by one or all of

the following: Labeled FOR USE WITH R-134a on set, labeled HFC-134a or

R-134a on gauge face, or by a Light Blue color on gauge face. In

addition, pressure/temperature scales on R-134a gauge sets are

different from R-12 manifold gauge sets.

         SYSTEM SERVICE VALVES

         SCHRADER-TYPE VALVES

NOTE:    Although similar in construction and operation to a tire

         valve, NEVER replace a Schrader-type valve with a tire valve.