1994 JEEP CHEROKEE Service Repair Manual

BASECOAT/CLEARCOAT
Basecoat/clearcoat paint finishes must be applied
in a very clean environment. Top-loader guns are
recommended for applying the basecoat paint and the
clearcoat paint.
Basecoat/clearcoat application is a two-stage pro-
cess. The basecoat is applied over the final primer
coat. The clearcoat is then applied over the basecoat.
The clearcoat provides the paint finish with a high
gloss and increased durability.
The work area should be well ventilated for
application of basecoat and clearcoat paints; es-
pecially when applying the clearcoat paint.
ACCENT PAINT
When applicable, argent accent paint (Fig. 9) is ap-
plied to the grille opening panel, sill crossmember
and radiator baffles. The argent paint coating covers
the rocker panel and extends upward 25 mm (1 in)
from the door panel lower edge.
PAINT REPAIR ON GALVANIZED METALS
Many body panels are made from galvanized sheet
metal. Proper surface preparation of galvanized pan-
els is important in regard to rust protection and the
finish coat.
Repaired surface areas on galvanized panels should
be sanded, cleaned and re-coated with Galva Prep or
a similar product.
Use only those primers recommended for use on
galvanized panels. Consult the paint suppliers prod-
uct and application instructions. Do not apply a base/
colorcoat directly on galvanized panel.
Fig. 4 Door Base/Color Coat Paint FinishÐYJ
Vehicles
Fig. 5 Front Body Basecoat/Clearcoat Paint
FinishÐXJ Vehicles
Fig. 6 Hood and Doors Basecoat/Clearcoat Paint
FinishÐXJ Vehicles
Fig. 7 Rear Body Basecoat/Clearcoat Paint
FinishÐXJ Vehicles
23 - 202 BODY COMPONENTSÐXJ VEHICLESJ

BUFFING AND POLISHING
Minor paint defects in a base/colorcoat can fre-
quently be removed by light sanding, buffing and
polishing. Wet sand the defect with 600 grit paper
soaked in mineral spirits.
Buff the surface area with a fine grade buffing
compound. Finish the repair with a quality polishing
compound to blend and restore the gloss.
BODY UNDERCOAT
Undercoat is applied to the exterior side of wheel-
houses and underbody panels.
PLASTIC COMPONENTS
Plastic components are molded from three different
types of plastic compounds. The three compounds are:
ABS (acrylo-nitrile, butadiene, styrene); polypropy-
lene and vinyl. Minor cracks in any of the three
types can be repaired with 3M 8101 structural adhe-
sive, or an equivalent product.
Fig. 8 Liftgate Basecoat/Clearcoat Paint FinishÐXJ
Vehicles
Fig. 9 Grille Opening Panel, Crossmember and
Baffle Argent Accent Paint
Fig. 10 Body Side Argent Accent Paint Finish
Fig. 11 Front Wheelhouse UndercoatÐXJ Vehicles
Fig. 12 Rear Wheelhouse UndercoatÐXJ Vehicles
JBODY COMPONENTSÐXJ VEHICLES 23 - 203

The three compounds can be identified with a
flame test (Fig. 15). To perform the test, first cut a
small sample of the material from a non-visible por-
tion of the plastic. Then apply an open flame to the
sample and observe the smoke or flame color.
ABS and polypropylene only require an open flame
for testing. However, vinyl must be burned in combi-
nation with copper.
To test vinyl, heat a length of solid copper wire un-
til it is red hot. Immediately apply the hot wire to
the plastic sample until some of the material adheres
to the copper. Then expose the copper wire and sam-
ple to an open flame (Fig. 15).
²ABS material will produce black smoke when
burned.
²Polypropylene will produce little or no smoke.
²Vinyl will produce a blue green flame when
burned in combination with copper.
EXTERIOR BODY COLORS
Exterior vehicle body colors are identified on the
Vehicle Code plate. The plate is located on the left
side of the dash panel in the engine compartment.
The color code location is described in the Introduc-
tion of this manual.
OEM paint colors are generally available from all
of the major paint suppliers. They are supplied in the
form of either mixing formulas or factory packaged
(pre-mixed) paint.
The exterior body and interior trim colors and cor-
responding JeepŸ paint codes are listed in the fol-
lowing charts.
Fig. 15 Plastic Flame Tests
Fig. 13 Underbody Center Section UndercoatÐXJ
Vehicles
Fig. 14 Underbody Rear Section (Above Fuel Tank)
UndercoatÐXJ Vehicles
23 - 204 BODY COMPONENTSÐXJ VEHICLESJ

XJ EXTERIOR PAINT CODES
XJ INTERIOR PAINT CODES
JBODY COMPONENTSÐXJ VEHICLES 23 - 205

YJ EXTERIOR PAINT CODES
YJ INTERIOR PAINT CODES
23 - 206 BODY COMPONENTSÐXJ VEHICLESJ

TORQUE SPECIFICATIONSÐXJ VEHICLES
JBODY COMPONENTSÐXJ VEHICLES 23 - 207

TORQUE SPECIFICATIONSÐACCESSORIES
23 - 208 BODY COMPONENTSÐXJ VEHICLESJ

HEATING AND AIR CONDITIONING
CONTENTS
page page
CLIMATE CONTROL SYSTEMÐXJ VEHICLES . 22
CLIMATE CONTROL SYSTEMÐYJ VEHICLES . 37
COMPRESSOR OVERHAUL............... 17
GENERAL INFORMATION.................. 1SERVICE DIAGNOSISÐELECTRICAL........ 14
SERVICE DIAGNOSISÐMECHANICAL........ 8
TORQUE SPECIFICATIONS................ 45
GENERAL INFORMATION
INDEX
page page
A/C Operation............................ 1
Compressor Oil Level...................... 6
Pressure Gauge and Manifold Assembly........ 2
Refrigerant (R-12)......................... 1
Service Precautions........................ 2Service Valves........................... 3
System Charge........................... 5
System Discharge......................... 4
System Evacuation........................ 4
A/C OPERATION
The compressor increases the pressure and temper-
ature of the refrigerant. The heated refrigerant vapor
is then pumped into the condenser where it cools by
the air passing over the condenser fins. As the refrig-
erant cools in the condenser, it condenses into a liq-
uid. Still under high pressure, the liquid refrigerant
passes into the receiver. The receiver acts as a reser-
voir to furnish refrigerant to the expansion (H) valve
at all times. From the receiver, the high pressure liq-
uid refrigerant passes to the expansion (H) valve.
The expansion (H) valve meters refrigerant into the
evaporator where a low pressure is maintained by
the suction side of the compressor. As it enters the
evaporator, the refrigerant immediately begins to
boil by absorbing heat from the air passing over the
evaporator core. Having given up its heat to boil the
refrigerant, the air is cooled and passes into the pas-
senger compartment of the vehicle. From the evapo-
rator the vaporized refrigerant is drawn back to the
compressor to repeat the cycle.
REFRIGERANT (R-12)
It is illegal to release R-12 into the atmosphere.
SAFETY PRECAUTIONS
WARNING: EXTREME CARE MUST BE TAKEN TO
PREVENT ANY LIQUID REFRIGERANT FROM COM-
ING IN CONTACT WITH THE SKIN AND ESPE-
CIALLY THE EYES. ALWAYS WEAR SAFETYGOGGLES WHEN SERVICING ANY PART OF THE
REFRIGERANT SYSTEM. IF EYE CONTACT IS
MADE, APPLY A FEW DROPS OF MINERAL OIL TO
THE EYES AND FLUSH WITH WATER FOR SEV-
ERAL MINUTES. SEEK MEDICAL ATTENTION IMME-
DIATELY.
The refrigerant used in the air conditioner system
is Refrigerant-12 (R-12). R-12 is nonexplosive, non-
flammable, non-corrosive, has practically no odor and
is heavier than air. Although it is classified as a safe
refrigerant, certain precautions must be observed to
protect the parts involved and the person who is
working on the unit. Liquid R-12, at normal atmo-
sphere pressures and temperatures, evaporates so
quickly that it has the tendency to freeze anything it
contacts.
WARNING: TO AVOID A DANGEROUS EXPLOSION,
NEVER WELD OR STEAM CLEAN NEAR AIR CON-
DITIONING LINES OR COMPONENTS. DO NOT
HEAT R-12 ABOVE 52ÉC (125ÉF).
The R-12 in the system is always under pressure.
Because the system is tightly sealed, heat applied to
any part could cause this pressure to build up exces-
sively.
JHEATING AND AIR CONDITIONING 24 - 1