1994 JEEP CHEROKEE weight

(9) Remove inboard shoe. Grasp ends of shoe and
tilt shoe outward to release springs from caliper pis-
ton (Fig. 8). Then remove shoe from caliper.
(10) Support caliper on box, mechanics stool, or se-
cure it to nearby suspension part with wire.Do not
allow brake hose to support caliper weight.
(11) Wipe caliper off with shop rags or towels.Do
not use compressed air. Compressed air can un-
seat dust boot and force dirt into piston bore.
(12) Inspect condition of caliper piston dust boot
(Fig. 9). Overhaul caliper if there is evidence of leak-
age past piston and dust boot. Then inspect caliper
bushings and boots (Fig. 9). Replace boots if torn or
cut. If bushings or boots are damaged, replace them.
DISC BRAKESHOE INSTALLATION
(1) Clean brakeshoe mounting ledge slide surfaces
of steering knuckle with wire brush. Then apply
light coat of Mopar multi-mileage grease to slide sur-
faces (Fig. 10).
(2) Lubricate caliper mounting bolts and bushings
(Fig. 10). Use GE 661 or Dow 111 silicone grease.(3) Keep new or original brakeshoes in sets.Do
not interchange them.
(4) Install inboard shoe in caliper (Fig. 11). Be
sure shoe retaining springs are fully seated in caliper
piston.
(5) Install outboard shoe in caliper (Fig. 12). Start
one end of shoe in caliper. Rotate shoe downward and
into place until shoe locating lugs and shoe spring
are seated.
(6) Verify that locating lugs on outboard shoe are
seated in caliper (Fig. 6).
(7) Install caliper. Position notches at lower end of
brakeshoes on bottom mounting ledge (Fig. 13). Then
install caliper over rotor and seat upper ends of
brakeshoes on top mounting ledge (Fig. 11).
CAUTION: Before securing the caliper, be sure the
caliper brake hose is not twisted, kinked or touch-
ing any chassis components. Also be sure the hose
is clear of all suspension and steering components.
Loosen and reposition the hose if necessary.
Fig. 7 Removing Outboard Brakeshoe
Fig. 8 Removing Inboard Brakeshoe
Fig. 9 Caliper Dust Boots And Bushing Locations
Fig. 10 Caliper Lubrication Points
5 - 26 BRAKESJ

BATTERY TESTING GENERAL INFORMATION
Before testing a battery, clean the top of the
battery case, posts and cable terminals.
Specific gravity is a ratio of the density of the elec-
trolyte and the density of pure water. The electrolyte
is composed of sulfuric acid and water. Acid makes
up approximately 35% of the electrolyte by weight,
or 24% by volume.
The condition of a battery may be determined from
the results of 2 tests:
²hydrometer test
²ability to supply current (battery load test)
Perform the hydrometer test first. If the specific
gravity is less than 1.235, (with battery at room tem-
perature) the battery must be charged before pro-
ceeding with further testing. A battery that will not
accept a charge is defective and further testing is not
necessary.
Completely discharged batteries may take sev-
eral hours to accept a charge. See Charging
Completely Discharged Battery.
A battery that has been fully charged but does not
pass the battery load test is defective.
A battery is fully charged when:
²all cells are gassing freely during charging
²3 corrected specific gravity tests, taken at 1-hour
intervals, indicate no increase in specific gravity.
ABNORMAL BATTERY DISCHARGING
(1) Corroded battery posts and terminals.
(2) Loose or worn generator drive belt.
(3) Electrical loads that exceed the output of the
charging system due to equipment or accessories in-
stalled after delivery.
(4) Slow driving speeds (heavy traffic conditions)
or prolonged idling with high-amperage draw sys-
tems in use.
(5) Defective circuit or component causing excess
IOD. Refer to Ignition Off Draw Diagnosis in this
group.
(6) Defective charging system.
(7) Defective battery.
HYDROMETER TEST
Before performing a hydrometer test, remove
battery caps and check electrolyte level. Add
distilled water as required.
Before testing, visually inspect battery for any
damage (cracked case or cover, loose post, etc.) that
would cause the battery to be defective. To use the
hydrometer correctly, hold it with the top surface of
the electrolyte at eye level. Refer to manufacturers
instructions for correct use of hydrometer.
Remove only enough electrolyte from the battery to
keep the float off the bottom of the hydrometer bar-
rel with pressure on the bulb released. Exercise care
when inserting the tip of the hydrometer into a cellto avoid damage to the separators. Damaged separa-
tors can cause premature battery failure.
Hydrometer floats are generally calibrated to indi-
cate the specific gravity correctly only at one fixed
temperature, 80ÉF (26.6ÉC). When testing the specific
gravity at any other temperature, a correction factor
is required.
The correction factor is approximately a specific
gravity value of 0.004, referred to as 4 points of spe-
cific gravity. For each 10ÉF above 80ÉF (5.5ÉC above
26.6ÉC), add 4 points. For each 10ÉF below 80ÉF
(5.5ÉC below 26.6ÉC), subtract 4 points. Always cor-
rect the specific gravity for temperature variation.
Test the specific gravity of the electrolyte in each
battery cell.
Example: A battery is tested at 10ÉF (-12.2ÉC) and
has a specific gravity of 1.240. Determine the actual
specific gravity as follows:
²Determine the number of degrees above or below
80ÉF:
80ÉF - 10ÉF = 70ÉF
²Divide the result above by 10:
70ÉF/10 = 7
²Multiply the result from the previous step by the
temperature correction factor (0.004):
7 x 0.004 = 0.028
²The temperature at testing was below 80ÉF, there-
fore the temperature correction is subtracted:
1.240 - 0.028 = 1.212
²The corrected specific gravity is 1.212.
The fully charged battery should have a tempera-
ture corrected specific gravity of 1.260 to 1.290.
If the specific gravity of all cells is above 1.235,
and cell variation is more than 50 points (0.050), it is
an indication that the battery is unserviceable.
If the specific gravity of one or more cells is less
than 1.235, charge the battery at a rate of approxi-
mately 5 amperes. Continue charging until 3 consec-
utive specific gravity tests, taken at 1 hour intervals,
are constant.
If the cell specific gravity variation is more than 50
points (0.050) after the charge period, replace the
battery.
When the specific gravity of all cells is above 1.235
and variation between cells is less than 50 points
(0.050), the battery may be tested under heavy load.
BATTERY OPEN CIRCUIT VOLTAGE TEST
A battery voltage (no load) test will show state of
charge of a battery that will pass the Battery Load
Test described in this section.Before proceeding
with this test or Battery Load Test, completely
charge battery as described in Battery Charging
in this section.
If a battery has a no load voltage reading of 12.4
volts or greater and will not endure a load test, it is
defective and should be replaced. Refer to Group 8B -
JBATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 3

ENGINE STARTER MOTOR SERVICE PROCEDURES
INDEX
page page
2.5L Starter General Information.............. 4
2.5L Starter Motor Removal/Installation......... 5
4.0L Starter General Information.............. 6
4.0L Starter Motor Removal/Installation......... 6General Information........................ 4
Park/Neutral Position Switch................. 6
Starter Relay Replacement.................. 4
GENERAL INFORMATION
This section will cover the starting system compo-
nent service procedures only. For diagnostic proce-
dures, refer to Group 8A - Battery/Starting/Charging
Systems Diagnostics.
Starting system components: battery, starter mo-
tor, starter relay, starter solenoid, ignition switch,
connecting wires and battery cables. A park/neutral
position switch is used with automatic transmissions.
STARTER RELAY REPLACEMENT
The starter relay is located in the Power Distribu-
tion Center (Figs. 1 and 2). Refer to underside of
Power Distribution Center cover for relay location.
(1) Disconnect negative cable from battery.
(2) Replace relay.
(3) Connect negative cable to battery.
(4) Test relay operation.
2.5L STARTER GENERAL INFORMATION
The 2.5L engine starter motor incorporates several
features to create an efficient, lightweight unit.
A planetary gear system (intermediate transmis-
sion) between the electric motor and pinion shaftmakes it possible to reduce the dimensions of the
starter. This also makes it possible to obtain a higher
rotational speed to produce the same torque at the
pinion.
The permanent magnet field consists of six two-
component high strength magnets. The magnets are
aligned according to their polarity and are perma-
nently fixed in the starter frame.
The brush holder plate consists of a plastic base-
plate with four tubular brush holders.
This unit is highly sensitive to hammering, shocks
and external pressure.
CAUTION: The starter motor MUST NOT BE
CLAMPED in a vise by the starter frame. Doing so
may damage the magnets. It may be clamped by the
mounting flange ONLY.
CAUTION: Do not connect starter motor incorrectly
when tests are being performed. The magnets may
be damaged and rendered unserviceable.
²Ensure cleanliness when performing repairs.
Fig. 1 Power Distribution CenterÐXJ
Fig. 2 Power Distribution CenterÐYJ
8B - 4 BATTERY/STARTER/GENERATOR SERVICEJ

4.0L STARTER GENERAL INFORMATION
The Mitsubishi starter motor is a light-weight unit
featuring a planetary gear drive and permanent
magnets for current induction.
The planetary gear drive is splined to both the ar-
mature shaft and overrunning clutch. Starter torque
is transmitted to the overrunning clutch pinion
through the planetary gears which provide higher ro-
tational speeds.
The starter magnetic field is produced by six per-
manent magnets. The magnets are mounted in the
starter frame and positioned according to polarity.
They are permanently attached to the frame and are
not removable.
The starter motor is activated by a solenoid
mounted on the overrunning clutch housing.
This unit is highly sensitive to hammering, shocks,
and external pressure.
CAUTION: The starter motor MUST NOT BE
CLAMPED in a vise by the starter frame. Doing so
may damage the magnets. It may be clamped by the
mounting flange ONLY.
CAUTION: Do not connect the starter motor incor-
rectly when performing tests. The magnets may be
damaged and rendered unserviceable.
²Ensure cleanliness when performing repairs.
²Metal chips are attracted by the magnets and may
not be completely removed from the starter frame.
Chips in the ring gear can lead to failure of the
starter.
4.0L STARTER MOTOR REMOVAL/INSTALLATION
(1) Disconnect negative cable from battery.
(2) Raise and support vehicle.(3) Disconnect battery wire and solenoid feed wire.
(4) Remove starter lower mounting bolt (Fig. 6).
(5) Remove starter upper mounting bolt and re-
move starter.
(6) To install starter motor, reverse the removal
procedures and torque mounting hardware as shown.
(7) Remove vehicle support and lower vehicle.
(8) Install negative cable to battery.
PARK/NEUTRAL POSITION SWITCH
Refer to Group 21 for diagnostic, removal and in-
stallation procedures.
Check linkage adjustment before replacing the
switch.
Fig. 6 Starter Motor Removal/Installation (Typical)
8B - 6 BATTERY/STARTER/GENERATOR SERVICEJ

(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.
The hone marks should INTERSECT at 50É to 60É for
proper seating of rings (Fig. 1).
(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper crosshatch
angle. The number of up and down strokes per
minute can be regulated to get the desired 50É to 60É
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
MEASURING WITH PLASTIGAGE
CRANKSHAFT MAIN BEARING CLEARANCE
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage, or equivalent. The fol-
lowing is the recommended procedures for the use of
Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) The total clearance of the main bearings can
only be determined by removing the weight of the
crankshaft. This can be accomplished by either of
two methods:
METHOD - 1 (PREFERRED)ÐShim the bear-
ings adjacent to the bearing to be checked. This will
remove the clearance between upper bearing shell
and the crankshaft. Place a minimum of 0.254 mm
(0.010 inch) shim between the bearing shell and the
adjacent bearing cap. Tighten the bolts to 18 Nzm (13
ft. lbs.) torque.
²ALL ENGINESÐWhen checking No.1 main bear-
ing; shim No.2 main bearing.²ALL ENGINESÐWhen checking No.2 main bear-
ing; shim No.1 and No.3 main bearing.
²ALL ENGINESÐWhen checking No.3 main bear-
ing; shim No.2 and No.4 main bearing.
²ALL ENGINESÐWhen checking No.4 main bear-
ing; shim No.3 and No.5 main bearing.
²2.5L ENGINEÐWhen checking No.5 main bear-
ing; shim No.4 main bearing.
²4.0L ENGINEÐWhen checking No.5 main bear-
ing; shim No.4 and No.6 main bearing.
²4.0L ENGINEÐWhen checking No.6 main bear-
ing; shim No.5 and No.7 main bearing.
²4.0L ENGINEÐWhen checking No.7 main bear-
ing; shim No.6 main bearing.
Remove all shims before assembling engine.
METHOD - 2 (ALTERNATIVE)ÐThe weight of
the crankshaft is supported by a jack under the coun-
terweight adjacent to the bearing being checked.
(3) Place a piece of Plastigage across the entire
width of the bearing cap shell (Fig. 2). Position the
Plastigage approximately 6.35 mm (1/4 inch) off cen-
ter and away from the oil holes. In addition, suspect
areas can be checked by placing the Plastigage in
that area. Tighten the bearing cap bolts of the bear-
ing being checked to 108 Nzm (80 ft. lbs.) torque.DO
NOT rotate the crankshaft or the Plastigage may
be smeared, giving inaccurate results.
(4) Remove the bearing cap and compare the width
of the flattened Plastigage with the scale provided on
the package (Fig. 3). Plastigage generally comes in 2
scales (one scale is in inches and the other is a met-
ric scale). Locate the band closest to the same width.
This band shows the amount of clearance. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken
(refer to Engine Specifications).
(5) Plastigage is available in a variety of clearance
ranges. The 0.025-0.076 mm (0.001-0.003 inch) range
is usually the most appropriate for checking engine
bearing clearances.
Fig. 1 Cylinder Bore Crosshatch Pattern
Fig. 2 Placement of Plastigage in Bearing Shell
JENGINES 9 - 3

2.5L ENGINE SERVICE PROCEDURES
INDEX
page page
Camshaft............................... 29
Camshaft Pin Replacement................. 31
Crankshaft Main Bearings.................. 40
Cylinder Block........................... 45
Engine AssemblyÐXJ Vehicles.............. 14
Engine AssemblyÐYJ Vehicles.............. 16
Engine Cylinder Head..................... 19
Engine Cylinder Head Cover................ 18
Engine Damper.......................... 13
Engine MountÐRear...................... 12
Engine MountsÐFront..................... 10
General Information........................ 9
Hydraulic Tappets........................ 24Oil Pan ................................ 32
Oil Pump............................... 33
Pistons and Connecting Rods............... 34
Rear Main Oil Seals...................... 44
Rocker Arms............................ 19
Specifications........................... 47
Timing Case Cover....................... 27
Timing Case Cover Oil Seal Replacement...... 26
Timing Chain and Sprockets................ 28
Valve Springs and Oil Seals................ 21
Valve Timing............................ 26
Valves and Valve Springs.................. 22
Vibration Damper........................ 26
GENERAL INFORMATION
The 2.5 liter (150 CID) four-cylinder engine is an
In-line, lightweight, overhead valve engine (Fig. 1).
This engine is designed for unleaded fuel.
The engine cylinder head has dual quench-type
combustion chambers that create turbulence and fast
burning of the air/fuel mixture. This results in good
fuel economy.
The cylinders are numbered 1 through 4 from front
to rear. The firing order is 1-3-4-2 (Fig. 2).
The crankshaft rotation is clockwise, when viewed
from the front of the engine. The crankshaft rotates
within five main bearings and the camshaft rotates
within four bearings.
BUILD DATE CODE
The engine Build Date Code is located on a ma-
chined surface on the right side of the cylinder block
between the No.3 and No.4 cylinders (Fig. 3).
Fig. 1 Engine Description
Fig. 2 Engine Firing Order
Fig. 3 Build Date Code Location
J2.5L ENGINE 9 - 9

a time, to avoid damaging the bridges.
(3) Remove the push rods.
(4) Remove the tappets through the push rod open-
ings in the cylinder head with Hydraulic Valve Tap-
pet Removal/Installation Tool C-4129-A (Fig. 13).
CLEANING
Clean each tappet assembly in cleaning solvent to
remove all varnish, gum and sludge deposits.
INSPECTION
Inspect for indications of scuffing on the side and
base of each tappet body.
Inspect each tappet base for concave wear with a
straightedge positioned across the base. If the base is
concave, the corresponding lobe on the camshaft is
also worn. Replace the camshaft and defective tap-
pets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 14).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Leak-Down
Tester 7980.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch) di-
ameter ball bearing on the plunger cap of the tappet.
(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram
until it contacts the ball bearing. DO NOT tighten
the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.(5) Swing the weighted arm onto the push rod and
pump the tappet plunger up and down to remove air.
When the air bubbles cease, swing the weighted arm
away and allow the plunger to rise to the normal po-
sition.
(6) Adjust the nose of the ram to align the pointer
with the SET mark on the scale of the tester and
tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the
base of the tester clockwise one revolution every 2
seconds.
(9) Observe the leak-down time interval from the
instant the pointer aligns with the START mark on
the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require 20-
110 seconds to leak-down. Discard tappets with leak-
down time interval not within this specification.
INSTALLATION
It is not necessary to charge the tappets with en-
gine oil. They will charge themselves within a very
short period of engine operation.
(1) Dip each tappet in Mopar Engine Oil Supple-
ment, or equivalent.
(2) Use Hydraulic Valve Tappet Removal/Installa-
tion Tool C-4129-A to install each tappet in the same
bore from where it was originally removed.
(3) Install the push rods in their original locations.
(4) Install the rocker arms and bridge and pivot
assemblies at their original locations. Loosely install
the capscrews at each bridge.
(5) Tighten the capscrews alternately, one turn at
a time, to avoid damaging the bridges. Tighten the
capscrews to 28 Nzm (21 ft. lbs.) torque.
(6) Pour the remaining Mopar Engine Oil Supple-
ment, or equivalent over the entire valve actuating
assembly. The Mopar Engine Oil Supplement, or
equivalent must remain with the engine oil for at
Fig. 13 Hydraulic Valve Tappet Removal/Installation
Tool C-4129-A
Fig. 14 Leak-Down Tester 7980
J2.5L ENGINE 9 - 25

CLEANING
Clean the cylinder bores thoroughly. Apply a light
film of clean engine oil to the bores with a clean lint-
free cloth.
INSTALLATION
(1) Install the piston rings on the pistons if re-
moved.
(2) Lubricate the piston and rings with clean en-
gine oil.
CAUTION: Ensure that connecting rod bolts do not
scratch the crankshaft journals or cylinder walls.
Short pieces of rubber hose slipped over the con-
necting rod bolts will provide protection during in-
stallation.
(3) Use a piston ring compressor to install the con-
necting rod and piston assemblies through the top of
the cylinder bores (Fig. 18).
(4) Ensure the arrow on the piston top points to
the front of the engine (Fig. 18).
(5) Raise the vehicle.
Each bearing insert is fitted to its respective jour-
nal to obtain the specified clearance between the
bearing and the journal. In production, the select fit
is obtained by using various-sized, color-coded bear-
ing inserts as listed in the Connecting Rod Bearing
Fitting Chart. The color code appears on the edge of
the bearing insert. The size is not stamped on inserts
used for production of engines.
The rod journal is identified during the engine pro-
duction by a color-coded paint mark on the adjacent
cheek or counterweight toward the flange (rear) end
of the crankshaft. The color codes used to indicate
journal sizes are listed in the Connecting Rod Bear-
ing Fitting Chart.
When required, upper and lower bearing inserts of
different sizes may be used as a pair (refer to Con-
necting Rod Bearing Fitting Chart). A standard sizeinsert is sometimes used in combination with a 0.025
mm (0.001 inch) undersize insert to reduce clearance
0.013 mm (0.0005 inch).
CAUTION: DO NOT intermix bearing caps. Each
connecting rod and bearing cap are stamped with
the cylinder number. The stamp is located on a ma-
chined surface adjacent to the oil squirt hole that
faces the camshaft side of the cylinder block.
(6) Install the connecting rod bearing caps and in-
serts in the same positions as removed.
CAUTION: Verify that the oil squirt holes in the rods
face the camshaft and that the arrows on the pis-
tons face the front of the engine.
(7) Install the oil pan and gaskets as outlined in
the installation procedure.
(8) Lower the vehicle.
(9) Install the engine cylinder head, push rods,
rocker arms, bridges, pivots and engine cylinder head
cover.
(10) Fill the crankcase with engine oil.
CRANKSHAFT MAIN BEARINGS
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the spark plugs.
(3) Raise the vehicle.
(4) Remove the oil pan and oil pump.
(5) Remove only one main bearing cap and lower
insert at a time (Fig. 1).
Fig. 18 Rod and Piston Assembly Installation
Fig. 1 Removing Main Bearing Caps and Lower Inserts
9 - 40 2.5L ENGINEJ