checking oil JEEP CHEROKEE 1988 Service Repair Manual
[x] Cancel search | Manufacturer: JEEP, Model Year: 1988, Model line: CHEROKEE, Model: JEEP CHEROKEE 1988Pages: 1378, PDF Size: 19.9 MB
Page 102 of 1378
PLACING SYSTEM IN OPERATION
After component service or replacement has been completed and
all connections have been made, evacuate system throughly with a
vacuum pump. Charge system with proper amount of refrigerant and
perform a leak test. Be sure to check all fittings that have been
opened. After system has been leak tested, make a system performance
check.
SANDEN SD508 5-CYLINDER OIL CHECKING
1) Discharge system using approved refrigerant
recovery/recycling equipment. Remove compressor belt and loosen
mounting bolts. Rotate compressor in brackets until filler plug is at
top. Clean area around filler plug and remove plug slowly. Rotate
front hub plate so notch in lobe is 110 degrees from the bottom. This
rotates ball end of top piston to align with oil fill port and allows
clearance for dipstick. See Fig. 1.
2) Insert compressor dipstick diagonally from right to left
until stop on dipstick contacts filler plug surface. Remove dipstick
and note oil fill level. Each mark on dipstick represents one ounce
of oil. Add oil if necessary to reach 3-4 ounce level.
Fig. 1: Sanden 5-Cylinder Oil Level Checking
YORK - 2-CYLINDER - PURGINE COMPRESSOR
Page 103 of 1378
1) Remove gauge set and place caps on service valve ports.
Back-seat the suction service valve to allow refrigerant to enter
compressor.
2) Loosen discharge port valve slightly. Loosen valve port
cap to allow refrigerant to force out air from compressor. Back-seat
the discharge valve and tighten the port cap. Compressor is ready for
service.
YORK - 2-CYLINDER COMPRESSOR OIL CHECKING
1) Operate system for 10 minutes, then stop and isolate
compressor. Loosen filler plug slowly to release any pressure in
crankcase.
2) Use dipstick to check oil level. See Fig. 2. Add oil as
necessary, then install plug with new "O" ring. Purge compressor of
air.
Fig. 2: York A/C Compressor Oil Level Dipstick (Check oil w/ shaft
keyway facing head)
Courtesy of Chrysler Motors.
Page 163 of 1378
CAN TAP INSTALLATION
FLAT TYPE SEAL CANS
On cam-lock or one-piece can taps, first turn the handle out
to the fully open position. Securely engage the locking lugs over the
flange of the can, and lock them in place by turning the cam lock or
locking nut. Screw the tap assembly into the adapter so the sealing
gasket is fully seated against the can top. Turn the tap inward to
pierce the can and close the tap. DO NOT open the tap until ready to
purge the service hose or dispense refrigerant into the system.
On 2-piece can taps, be certain the tap handle is turned
fully in, so it is closed. Check that the locking base is turned to
its outer limit. Securely engage the locking lugs over the can
flange. Turn the entire tap assembly (without disturbing the closed
setting) down into the locking base to pierce the can. Do not open
the tap until ready to dispense into system.
SCREW TYPE SEAL CANS
Ensure can tap is fully closed. Screw refrigerant can into
can tap fitting until tight. This will pierce the can. Connect tap to
center hose on manifold gauge set. DO NOT open tap until ready to
dispense R-12 into system.
WARNING: DO NOT open high side hand valve while air conditioning
system is in operation. This high pressure could rupture
can or possibly burst fitting at safety can valve,
resulting in damage and physical injury.
COMPRESSOR OIL CHECK
GENERAL PROCEDURES
Some models have compressor-mounted service valves that allow
oil checking by isolating the compressor. On all others, system must
be discharged, using approved refrigerant recovery/recycling
equipment, and compressor may need to be removed to check oil. After
oil level is checked and adjusted, A/C system must be evacuated and
recharged.
ISOLATING COMPRESSOR
1) Connect manifold gauge set to service valves on the
compressor. Close both gauge valves. Open both service valves to
themid-position.
2) Start engine and operate air conditioning. Turn suction
service valve slowly clockwise toward front-seated position. When
suction pressure is reduced to zero or less, stop engine and quickly
close suction service valve (front-seated).
3) Front-seat the discharge valve. Loosen oil check plug
slowly to release any internal pressure. Service valves can now be
removed from compressor and compressor removed from vehicle (if
necessary). Purge compressor after servicing.
PURGING COMPRESSOR
1) Remove gauge set and place caps on service valve ports.
Back-seat the suction service valve to allow refrigerant to enter
compressor.
Page 164 of 1378
2) Loosen discharge port valve slightly. Loosen valve port
cap to allow refrigerant to force out air from compressor. Back-seat
the discharge valve and tighten the port cap. Compressor is ready for
service.
REFRIGERATION OIL
Only new, pure, moisture-free refrigeration oil should be
used in the air conditioning system. This oil is highly refined and
dehydrated (moisture content less than 10 parts per million).
Refrigeration oil container must be kept tightly closed at
all times when not in use, or moisture will be absorbed from the air
and introduced into the refrigeration system.
NIPPONDENSO 10-CYLINDER
SHAFT SEAL
NOTE: Check compressor refrigerant oil level when replacing seals.
See COMPRESSOR REFRIGERANT OIL CHECKING article in this
section.
Removal
1) Hold clutch hub stationary and remove center nut. Screw
remover into center of hub. Turn center bolt to remove pressure plate.
2) Remove shims from shaft. Remove snap ring from inside of
pulley. Tap pulley off of shaft with plastic mallet. Be careful not
to distort pulley while removing.
3) Disconnect clutch coil wires from compressor housing.
Remove snap ring inside coil and lift coil off compressor. Pry dust
seal out from around compressor shaft (if equipped).
4) Place shaft key remover on shaft and turn to remove key.
Remove drain plug (if equipped). Remove bolts holding service valves
to body of compressor and remove valves. Discard "O" rings. Drain oil
out of compressor.
5) Remove 6 through bolts from front head of compressor and
discard washers. Tap head loose from compressor, being careful not to
scratch sealing surfaces. Remove snap ring (if equipped) from front
housing. Press seal plate out. Remove seal from shaft. See Fig. 1.
Installation
1) Lubricate shaft seal with clean refrigerant oil. Place on
compressor shaft. Lubricate seal plate (and "O" ring, if equipped) and\
install in front housing. Install snap ring (if equipped).
2) Place front housing on compressor body. Using new
washers, install through bolts. Tighten bolts evenly and alternately
to 18 ft. lbs. (24 N.m). Install shaft key with installer and plastic
mallet. Insert dust seal into front of compressor.
3) Install drain plug using new gasket. Add correct amount
of refrigerant oil to compressor. If service valves were removed,
coat new "O" rings with refrigerant oil and install service valves.
4) Place clutch coil on compressor and install snap ring.
Install shims on shaft to adjust clearance between pressure plate and
rotor to .016-.028" (.41-.71 mm). Tighten shaft nut to 12 ft. lbs. (1\
6
N.m). See REFRIGERANT OIL & R-12 SPECIFICATIONS table for system
capacities.
SANKYO/SANDEN 5-CYLINDER COMPRESSOR SERVICING
NOTE: During the past year, Sankyo International (USA), Inc. has
changed its name to Sanden International (USA), Inc.
Page 615 of 1378
On cast cylinder heads, if warpage exceeds .003" (.08 mm)
in a 6" span, or .006" (.15 mm) over total length, cylinder head must
be resurfaced. On most aluminum cylinder heads, if warpage exceeds .
002" (.05 mm) in any area, cylinder head must be resurfaced. Warpage
specification may vary with manufacturer.
Cylinder head thickness should be measured to determine
amount of material which can be removed before replacement is
required. Cylinder head thickness must not be less than manufacturer's
specifications.
If cylinder head required resurfacing, it may not align
properly with intake manifold. On "V" type engines, misalignment is
corrected by machining intake manifold surface that contacts cylinder
head. Cylinder head may be machined on surface that contacts intake
manifold.
Using oil stone, remove burrs or scratches from all sealing
surfaces.
VALVE SPRINGS
Inspect valve springs for corroded or pitted valve spring
surfaces which may lead to breakage. Polished spring ends caused by
a rotating spring, indicates that spring surge has occurred. Replace
springs showing evidence of these conditions.
Inspect valve springs for squareness using a 90 degree
straightedge. See Fig. 4. Replace valve spring if out-of-square
exceeds manufacturer's specification.
Fig. 4: Checking Valve Spring Squareness - Typical
This Graphic For General Information Only
Using vernier caliper, measure free length of all valve
springs. Replace springs if not within specification. Using valve
Page 637 of 1378
length of cylinder block at several points.
If warpage exceeds specifications, deck must be resurfaced.
If warpage exceeds manufacturer's maximum tolerance for material
removal, replace block.
DECK HEIGHT
Distance from the crankshaft centerline to the block
deck is termed the deck height. Measure and record front and rear main
journals of crankshaft. To compute this distance, install crankshaft
and retain with center main bearing and cap only. Measure distance
from the crankshaft journal to the block deck, parallel to the
cylinder centerline.
Add one half of the main bearing journal diameter to distance
from crankshaft journal to block deck. This dimension should be
checked at front and rear of cylinder block. Both readings should be
the same.
If difference exceeds specifications, cylinder block must be
repaired or replaced. Deck height and warpage should be corrected at
the same time.
MAIN BEARING BORE & ALIGNMENT
For checking main bearing bore, remove all bearings from
cylinder block and main bearing caps. Install main bearing caps in
original location. Tighten bolts to specification. Using inside
micrometer, measure main bearing bore in 2 areas 90 degrees apart.
Determine bore size and out-of-round. If diameter is not within
specification, block must be align-bored.
For checking alignment, place a straightedge along centerline
of main bearing saddles. Check for clearance between straightedge and
main bearing saddles. Block must be align-bored if clearance is
present.
EXPANSION PLUG REMOVAL & INSTALLATION
Removal
Drill a hole in the center of expansion plug. Remove with
screwdriver or punch. Use care not to damage sealing surface.
Installation
Ensure sealing surface is free of burrs. Coat expansion plug
with sealer. Use a wooden dowel or pipe of slightly smaller diameter,
install expansion plug. Ensure expansion plug is evenly located.
OIL GALLERY PLUG REMOVAL & INSTALLATION
Removal
Remove threaded oil gallery plugs using the appropriate
wrench. Soft, press-in plugs are removed by drilling into plug and
installing a sheet metal screw. Remove plug with slide hammer or
pliers.
Installation
Ensure threads or sealing surface is clean. Coat threaded oil
gallery plugs with sealer and install. Replacement soft press-in plugs
are driven in place with a hammer and drift.
CAMSHAFT
* PLEASE READ THIS FIRST *
Page 648 of 1378
Engine pre-oiling can be done using pressure oiler (if
available). Connect pressure oiler to cylinder block oil passage
such as oil pressure sending unit. Operate pressure oiler long enough
to ensure correct amount of oil has filled crankcase. Check oil level
while pre-oiling.
If pressure oiler is not available, disconnect ignition
system. Remove oil pressure sending unit and replace with oil pressure
test gauge. Using starter motor, rotate engine starter until gauge
shows normal oil pressure for several seconds. DO NOT crank engine
for more than 30 seconds to avoid starter motor damage.
Ensure oil pressure has reached the most distant point from
the oil pump. Reinstall oil pressure sending unit. Reconnect ignition
system.
INITIAL START-UP
Start the engine and operate engine at low speed while
checking for coolant, fuel and oil leaks. Stop engine. Recheck coolant
and oil level. Adjust if necessary.
CAMSHAFT
Break-in procedure is required when a new or reground
camshaft has been installed. Operate and maintain engine speed between
1500-2500 RPM for approximately 30 minutes. Procedure may vary due to
manufacturers recommendations.
PISTON RINGS
Piston rings require a break-in procedure to ensure seating
of rings to cylinder walls. Serious damage may occur to rings if
correct procedures are not followed.
Extremely high piston ring temperatures are produced obtained
during break-in process. If rings are exposed to excessively high RPM
or high cylinder pressures, ring damage can occur. Follow piston ring
manufacturer's recommended break-in procedure.
FINAL ADJUSTMENTS
Check or adjust ignition timing and dwell (if applicable).
Adjust valves (if necessary). Adjust carburetion or injection idle
speed and mixture. Retighten cylinder heads (if required). If
cylinder head or block is aluminum, retighten bolts when engine is
cold. Follow the engine manufacturer's recommended break-in procedure
and maintenance schedule for new engines.
NOTE: Some manufacturer's require that head bolts be retightened
after specified amount of operation. This must be done to
prevent head gasket failure.
Page 889 of 1378
1) Disconnect pick-up coil leads from HEI/EST module
terminals "N" and "P". Set ohmmeter to middle scale and connect one
lead to either pick-up coil lead and the other lead to distributor
housing. See Fig. 9. Flex pick-up coil leads by hand to check for
intermittent shorts to ground. Reading should be infinity at all
times. If not, replace pick-up coil.
2) Connect ohmmeter between both pick-up coil leads. Check
for intermittent opens by flexing wires and connectors. Resistance
should be 500-1500 ohms. If not, replace pick-up coil.
Fig. 9: Checking Distributor Pick-Up Coil, Integral coil system
shown. External coil testing is similar
Courtesy of General Motors Corp.
Page 928 of 1378
PO W ER S TE ER IN G G EN ER AL S ER VIC IN G
1988 J e ep C hero ke e
1988 STEERING
Jeep Power Steering General Servicing
Cherokee, Comanche, Grand Wagoneer, Pickup, Wagoneer,
Wrangler
LUBRICATION
SERVICE INTERVALS
Check fluid at every oil change.
CHECKING FLUID LEVEL
Check fluid level with engine stopped and fluid hot or cold.
Fluid level must be at "FULL-HOT" or "FULL-COLD" mark on dipstick. On
models with remote reservoir, keep fluid level 0.5-1.0" from top of
reservoir with wheels turned fully to left.
RECOMMENDED FLUID TABLE
\
\
\
\
\
\
Application Part Number
Jeep ............................................. 8993342
\
\
\
\
\
\
REFILLING & BLEEDING SYSTEM
1) Fill reservoir to correct level. Operate engine until
fluid reaches normal operating temperature. Stop engine. Add fluid (if
necessary). Turn wheels to full left position. Add fluid to reservoir
to fill to "FULL-COLD" mark on dipstick.
2) Start and operate engine at fast idle. Recheck reservoir
level. Add to "FULL-COLD" mark on dipstick. Turn wheels from side to
side without contacting stops. Maintain fluid level just above pump
body.
3) When air is removed, return wheels to straight-ahead
position. Operate engine 2-3 minutes. Stop engine. Road test vehicle.
Recheck fluid level. Level should be at "FULL-HOT" position after
system has stabilized. Add fluid (if necessary). DO NOT overfill.
BELT TENSION (Tension in Lbs. Using Boroughs Tension Gauge)
\
\
\
\
\
\
Application New Belt Used Belt
Jeep ................ ( 1) 125-155 ............... 90-115
( 1) - Cherokee, Comanche and Wagoneer is 120-140 lbs.
\
\
\
\
\
\
TROUBLE SHOOTING
Refer to TROUBLE SHOOTING - BASIC PROCEDURES article in the
GENERAL TROUBLE SHOOTING section.
TESTING
Page 943 of 1378
To test crankcase ventilation system, start engine and allow
it to reach normal operating temperature. Make sure engine is idling
at normal curb idle, and perform following checks:
1) Remove PCV valve from its mounting. If valve is
functioning properly, hissing noise will be heard as air passes
through it. Strong vacuum should be felt when your finger is placed
over valve inlet.
2) While finger is over inlet, check for presence of vacuum
leaks in hose line and at all connections. Reinstall PCV valve,
remove crankcase air inlet hose at air cleaner.
3) Loosely hold piece of stiff paper over opening at end of
inlet hose. Paper should be sucked against hose opening with
noticeable force after sufficient time has elapsed for crankcase
pressure to lower (usually about a minute). For final check, stop
engine, remove PCV valve and shake it. Metallic clicking noise should
be heard, indicating valve is free.
4) If system passes both engine running and stopped tests,
it is functioning properly. No further tests are required. If it has
failed either test, replace appropriate components and retest. If it
does not pass on second try, clean system.
MAINTENANCE
Engine may idle slow or rough due to clogged ventilator
valve or system. Therefore, never adjust carburetor idle without
first checking valve and system.
If ventilator valve or system becomes clogged, all crankcase
ventilation will stop, and serious engine damage could result.
Although following manufacturers' service procedures give
specific intervals, it is recommended the crankcase ventilation
system be checked more frequently if vehicle is operated under severe
conditions (extreme dust, prolonged idling, trailer hauling or short
trips in cold weather).
PCV VALVE
Replace PCV valve every 30,000 miles. Valve is located on
rocker arm cover of 4-cylinder, 6-cylinder and V6 models and on
intake manifold of V8 models.
FILTER ELEMENT
Clean filter element every 30,000 miles. Filter is located
inside air cleaner of 4-cylinder, 6-cylinder and V6 models and in oil
filler cap of V8 models.