JEEP CHEROKEE 1988 Service Repair Manual

Fig. 5: Fan Module Removal

Fig. 6: Fan Motor Removal & Installation

Fig. 7: Alignment Groove in Fan Module Bushing

Fig. 8: Alignment Dowel (Fan Module to Motor)
WIRING DIAGRAMS

Fig. 9: Wiring Diagrams (With A/C)

Fig. 10: Wiring Diagrams (Without A/C)

EN G IN E O IL P A N R EM OVA L

1988 J e ep C hero ke e
1988 ENGINES
Jeep - Engine Oil Pan Removal
Cherokee, Comanche, Wagoneer
Wrangler, Grand Wagoneer
NOTE: Only engine applications with special oil pan removal and
installation procedures are included in this article.
Illustrations of most manufacturer's oil pans and attaching
hardware are provided.
Fig. 1: View of Jeep 2.5L Oil Pan
Courtesy of Chrysler Motors.

Fig. 2: View of Jeep 4.0L & 4.2L Oil Pan
Courtesy of Chrysler Motors.

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EN G IN E O VER HAU L P R O CED URES - G EN ER AL IN FO RM ATIO N

1988 J e ep C hero ke e
Engine Overhaul Procedures - General Information
ALL PISTON ENGINES
* PLEASE READ THIS FIRST *
Examples used in this article are general in nature and do
not necessarily relate to a specific engine or system. Illustrations
and procedures have been chosen to guide mechanic through engine
overhaul process. Descriptions of processes of cleaning, inspection,
assembly and machine shop practice are included.
Always refer to appropriate engine overhaul article in the
ENGINES section for complete overhaul procedures and specifications
for the vehicle being repaired.
ENGINE IDENTIFICATION
The engine may be identified from its Vehicle Identification
Number (VIN) stamped on a metal tab. Metal tab may be located in
different locations depending on manufacturer. Engine identification
number or serial number is located on cylinder block. Location varies
with manufacturer.
INSPECTION PROCEDURES
* PLEASE READ THIS FIRST *
NOTE: Always refer to appropriate engine overhaul article in the
ENGINES section for complete overhaul procedures and
specifications for the vehicle being repaired.
GENERAL
Engine components must be inspected to meet manufacturer's
specifications and tolerances during overhaul. Proper dimensions and
tolerances must be met to obtain proper performance and maximum engine
life.
Micrometers, depth gauges and dial indicator are used for
checking tolerances during engine overhaul. Magnaflux, Magnaglo, dye-
check, ultrasonic and x-ray inspection procedures are used for parts
inspection.
MAGNETIC PARTICLE INSPECTION
Magnaflux & Magnaglo
Magnaflux is an inspection technique used to locate material
flaws and stress cracks. The part in question is subjected to a strong
magnetic field. The entire part, or a localized area, can be
magnetized. The part is coated with either a wet or dry material that
contains fine magnetic particles.
Cracks which are outlined by the particles cause an
interruption in the magnetic field. The dry powder method of Magnaflux
can be used in normal light. A crack will appear as an obvious bright
line.
Fluorescent liquid is used in conjunction with a blacklight
in a second Magnaflux system called Magnaglo. This type of inspection
demands a darkened room. The crack will appear as a glowing line in
this process. Both systems require complete demagnetizing upon

completion of the inspection. Magnetic particle inspection applies to
ferrous materials only.
PENETRANT INSPECTION
Zyglo
The Zyglo process coats the material with a fluorescent dye
penetrant. The part is often warmed to expand cracks that will be
penetrated by the dye. When the coated part is subjected to inspection
with a blacklight, a crack will glow brightly. Developing solution
is often used to enhance results. Parts made of any material, such as
aluminum cylinder heads or plastics, may be tested using this process.
Dye Check
Penetrating dye is sprayed on the previously cleaned
component. Dye is left on component for 5-45 minutes, depending upon
material density. Component is then wiped clean and sprayed with a
developing solution. Surface cracks will show up as a bright line.
ULTRASONIC INSPECTION
If an expensive part is suspected of internal cracking,
Ultrasonic testing is used. Sound waves are used for component
inspection.
X-RAY INSPECTION
This form of inspection is used on highly stressed
components. X-ray inspection maybe used to detect internal and
external flaws in any material.
PRESSURE TESTING
Cylinder heads can be tested for cracks using a pressure
tester. Pressure testing is performed by plugging all but one of the
holes in the head and injecting air or water into the open passage.
Leaks are indicated by the appearance of wet or damp areas when using
water. When air is used, it is necessary to spray the head surface
with a soap solution. Bubbles will indicate a leak. Cylinder head may
also be submerged in water heated to specified temperature to check
for cracks created during heat expansion.
CLEANING PROCEDURES
* PLEASE READ THIS FIRST *
NOTE: Always refer to appropriate engine overhaul article in the
ENGINES section for complete overhaul procedures and
specifications for the vehicle being repaired.
GENERAL
All components of an engine do not have the same cleaning
requirements. Physical methods include bead blasting and manual
removal. Chemical methods include solvent blast, solvent tank, hot
tank, cold tank and steam cleaning of components.
BEAD BLASTING
Manual removal of deposits may be required prior to bead
blasting, followed by some other cleaning method. Carbon, paint and