1991 MITSUBISHI MONTERO radiator

complete cooling system. Test components as follows, following tool
manufacturer's instructions.
Radiator Cap
Visually inspect radiator cap, then dip cap into water and
connect to tester. Pump tester to bring pressure to upper limit of cap
specification. If cap fails to hold pressure, replace cap.
Fig. 2: Testing Radiator Pressure Cap
Cooling System
1) With engine off, wipe radiator filler neck seat clean.
Fill radiator to correct level. Attach tester to radiator and pump
until pressure is at upper level of radiator rating.
2) If pressure drops, inspect for external leaks. If no leaks
are apparent, detach tester and run engine until normal operating
temperature is reached. Reattach tester and observe. If pressure
builds up immediately, a possible leak exists from a faulty head
gasket or crack in head or block.
NOTE: Pressure may build up quickly. Release any excess pressure
or cooling system damage may result.
3) If there is no immediate pressure build up, pump tester to
within system pressure range (on radiator cap). Vibration of gauge
pointer indicates compression or combustion leak into cooling system.
Isolate leak by shorting each spark plug wire to cylinder block. Gauge
pointer should stop or decrease vibration when leaking cylinder is
shorted.

Removal (Montero)
1) Move temperature control lever to WARM position. Drain
coolant from vehicle. Disconnect heater hoses from heater unit. See
Fig. 1.
2) Remove lap heater ducts. Remove hood release bracket.
Using screwdriver, release tabs and remove left and right demister
grilles. Remove glove box frame attaching screws, and remove glove
box. Remove passenger lap heater duct.
3) Using screwdriver and shop towel, carefully pry at top
center of instrument cluster cover, and remove cover. Remove 2 screws
at bottom of instrument panel and one bolt at top of instrument panel.
Gently pull instrument cluster out, and disconnect speedometer cable
and electrical connections. Remove instrument cluster.
4) Remove 4 screws, and disconnect electrical connections on
back of instrument cluster. Remove instrument cluster. Handle
instrument cluster carefully. Instrument cluster can be damaged if
dropped.
5) Remove center console knobs and side screw plugs. Remove
screws, disconnect electrical connections and remove console. Remove 6
bolts and console bracket (center dash reinforcement). Disconnect
radio connections while removing console bracket.
6) Remove horn pad and steering wheel retaining nut. Mark
steering wheel and steering shaft for reassembly reference. Using
steering wheel puller, remove steering wheel.
7) Using screwdriver, carefully pry out dash plug at upper
center of dash panel. Remove 3 upper dash mounting nuts, one upper
screw above steering column, and 2 lower mounting screws. Remove dash
panel.
8) Remove control cables at heater unit. Remove heater unit
attaching screws. Remove heater ducts. Remove heater unit. Remove
heater control lever arm.
9) Remove heater control valve cover. Remove heater pipe and
heater control valve. Disconnect control arm linkage. Remove control
arm. Remove heater core by moving it sideways.
Installation
1) To install, reverse removal procedure. Insert heater hoses
fully into pipes, and clamp securely to prevent leaks. Connect heater
hoses with 1-1.2" (25-30 mm) overlap on outlet.
2) When filling radiator with coolant, first open heater
control valve fully and run engine to circulate coolant and discharge
air from inside heater and engine cooling system. Stop engine, and add
coolant.
3) Adjust all control cables. When installing heater hose
grommets, apply sealer. After installing heater control assembly,
ensure each lever operates smoothly.
Removal (Pickup & Ram-50)
1) Disconnect battery ground cable. Place heater control
lever to far right. Drain coolant. Using trim stick, pry out hazard
switch and remove electrical connection. Remove 4 instrument cluster
cover screws, and remove cover. Remove 4 instrument cluster screws.
Tilt instrument cluster out, and disconnect speedometer cable and
electrical connections. Remove cluster.
2) Remove fuse box cover and fuse box assembly. Remove glove
box. Remove defroster air ducts. Disconnect heater control cables.
Using trim stick, pry under and remove speaker grilles. Remove clock
or coin box in center of dash. Remove center dash hole cover (located
above clock).
3) Remove 2 center support cover screws, and remove cover.
Remove shift knob and 6 console attaching screws. Remove console.
Ensure all electrical connections are free of dash panel. Remove 3 top
nuts, one bolt above steering column, and side and lower attaching

screws. Remove dash panel.
4) Remove blower duct, center duct and defroster ducts. See
Fig. 2. Disconnect heater wiring harness from heater unit. Remove
heater center support brackets. Remove heater unit. Remove heater core
cover plate and joint hose. Remove heater core from heater unit.
Installation
1) To install, reverse removal procedure. Insert heater hoses
fully into pipes, and clamp securely to prevent leaks.
2) When filling radiator with coolant, first open heater
control valve fully and run engine to circulate coolant and discharge
air from inside heater and engine cooling system. Stop engine, and add
coolant.
3) Adjust all control cables. When installing heater hose
grommets, apply sealer. After installing heater control assembly,
ensure each lever operates smoothly.
HEATER CONTROL PANEL
Removal (Montero)
1) Remove heater control knob and heater fan switch knob.
Remove center console. Remove defroster nozzle at temperature control
cable side.
2) Remove lap heater duct and glove box stopper, and push
glove box forward and down. Disconnect inside/outside control cable
from blower assembly.
3) Disconnect control cables from heater unit. Remove heater
control panel mounting screws, and pull out panel slightly. Disconnect
heater fan switch harness connectors. Remove heater control panel.
Remove heater fan switch from heater control panel.
Installation
1) Place air outlet change-over lever at closed position.
With heater side air outlet change-over damper lever in position,
connect inner cable to lever, and secure cable casing using clips.
2) Place heater control lever at OFF position. With heater
control lever in position, connect inner cable to lever, and secure
cable casing using clips.
3) Place inside/outside air change-over lever at INSIDE
position. With heater side inside/outside air change-over damper lever
in position, connect inner cable to lever, and secure cable casing
using clips.
4) Set control lever to each position to check for correct
operation. If lever does not operate correctly, adjust by moving outer
wire at clipped point. Ensure each control lever moves smoothly. If
any noise or stiff movement exists, apply multipurpose grease to all
moving parts.
NOTE: When mounting heater control panel to instrument panel,
tighten upper bolts to instrument panel so they also secure
center panel.
Removal & Installation (Pickup & Ram-50)
Remove cluster panel. Remove all control cables at heater.
Remove heater control panel. To install, reverse removal procedure.
Adjust cables as necessary.
WIRING DIAGRAMS

Parking Brake Switch ...................... Analog Instrument Panels
Park Lights ........................................ Exterior Lights
Park/Neutral Position Switch .............................. Starters
Engine Performance
Anti-Theft System
Body Control Module
Perimeter Lighting Control Relay ................... Exterior Lights
Power Amplifier ..................................... Power Antennas
Power Antenna Module ................................ Power Antennas
Power Antenna Motor ................................. Power Antennas
Power Distribution Center ....................... Power Distribution
Generators & Regulators
Starters
Power Door Lock Motors ............................ Power Door Locks
Power Mirror Motors .................................. Power Mirrors
Memory Systems
Power Sliding Door Controller .............. Power Sliding Side Door
Power Seat Motors ...................................... Power Seats
Memory Systems
Power Steering Pressure Switch .................. Engine Performance
Power Top Motor .............................. Power Convertible Top
Power Top Relay(s) ........................... Power Convertible Top\
Powertrain Control Module ....................... Engine Performance
Analog Instrument Panels
Cruise Control Systems
Data Link Connectors
Generators & Regulators
Starters
Power Window Motors .................................. Power Windows
Power Window Relay(s) ................................ Power Windows\
Radiator Fan Motor(s) ........................ Electric Cooling Fans\
Radiator Fan Relay(s) ........................... Engine Performance\
Electric Cooling Fans
Rainsense Module .............................. Wiper/Washer Systems
Raise Relay .................................. Power Convertible Top
Remote Anti-Theft Personality (RAP) Module ....... Anti-Theft System\
Starters
Warning Systems
Seat Belt Pretensioners ................... Air Bag Restraint System
Seat Belt Retractor Solenoid .................... Passive Restraints
Seat Belt Switch .......................... Air Bag Restraint System
Passive Restraints
Shift Interlock Solenoid ................... Shift Interlock Systems
Shift Lock Actuator ........................ Shift Interlock Systems
Side Marker Lights ................................. Exterior Lights
SIR Coil Assembly (Clockspring) ........... Air Bag Restraint System\
Slip Ring (Clockspring) ................... Air Bag Restraint System\
Steering Column Switches
SRS Control Module ........................ Air Bag Restraint System
Starter Motor ............................................. Starters
Starter Interrupt Relay ................................... Starters
Starter Solenoid .......................................... Starters
Starter Relay ............................................. Starters
Steering Wheel Position Sensor .................... Anti-Lock Brakes
Stoplights ......................................... Exterior Lights
Stoplight Switch ................................ Engine Performance
Cruise Control Systems
Anti-Lock Brakes
Sun Roof ECU ........................................ Power Sun Roof
Sun Roof Motor ...................................... Power Sun Roof
Sun Roof Position Sensor ............................ Power Sun Roof
Taillights ......................................... Exterior Lights
Throttle Position (TP) Sensor ................... Engine Performance\

CATALYTIC CONVERTER
Continued operation of vehicle with a severe malfunction
could cause converter to overheat, resulting in possible damage to
converter and vehicle.
COOLANT (PROPYLENE-GLYCOL FORMULATIONS)
CAUTION: To avoid possible damage to vehicle use only ethylene-glycol
based coolants with a mixture ratio from 44-68% anti-freeze.
DO NOT use 100% anti-freeze as it will cause the formation
of cooling system deposits. This results in coolant
temperatures of over 300
\b F (149\bC) which can melt plastics.
100% anti-freeze has a freeze point of only -8\b F (-22\bC).
CAUTION: Propylene-Glycol Mixtures has a smaller temperature range
than Ethylene-Glycol. The temperature range (freeze-boil)
of a 50/50 Anti-Freeze/Water Mix is as follows:
Propylene-Glycol -26
\b F (-32\bC) - 257\b F (125\bC)
Ethylene-Glycol -35\b F (-37\bC) - 263\b F (128\bC)
CAUTION: Propylene-Glycol/Ethylene-Glycol Mixtures can cause the
destabilization of various corrosion inhibitors. Also
Propylene-Glycol/Ethylene-Glycol has a different specific
gravity than Ethylene-Glycol coolant, which will result in
inaccurate freeze point calculations.
ELECTROSTATIC DISCHARGE SENSITIVE (ESD) PARTS
WARNING: Many solid state electrical components can be damaged by
static electricity (ESD). Some will display a warning label,
but many will not. Discharge personal static electricity by
touching a metal ground point on the vehicle prior to
servicing any ESD sensitive component.
ENGINE OIL
CAUTION: Never use non-detergent or straight mineral oil.
FUEL SYSTEM SERVICE
WARNING: Relieve fuel system pressure prior to servicing any fuel
system component (fuel injection models).
HALOGEN BULBS
WARNING: Halogen bulbs contain pressurized gas which may explode if
overheated. DO NOT touch glass portion of bulb with bare
hands. Eye protection should be worn when handling or working
around halogen bulbs.
RADIATOR CAP
CAUTION: Always disconnect the fan motor when working near the
radiator fan. The fan is temperature controlled and could
start at any time even when the ignition key is in the OFF
position. DO NOT loosen or remove radiator cap when cooling
system is hot.
RADIATOR FAN

WARNING: Keep hands away from radiator fan. Fan is controlled by a
thermostatic switch which may come on or run for up to
15 minutes even after engine is turned off.
WARRANTY INFORMATION
CAUTION: Always refer to customer's copy of warranty information for
specific model application and/or coverage limitations.
NEW VEHICLE LIMITED WARRANTY
Covers all manufacturer-installed parts and components for
any repairs, replacements or adjustments needed to correct defects in
materials or workmanship under normal use and maintenance for 36
months or 36,000 miles, whichever comes first, from date of delivery
to the first retail buyer or first date of use.
POWERTRAIN LIMITED WARRANTY
Upon expiration of New Vehicle Limited Warranty, this
warranty covers powertrain against defects in materials or workmanship
up to a maximum of 36 months or 50,000 miles, whichever occurs first.
On 1991-96 models, warranty period is extended to 5 years or 60,000
miles, whichever occurs first. See copy of warranty for specific
components covered.
BATTERY WARRANTY
Covers replacement of original battery for 12 months or 12,
000 miles, whichever occurs first.
AIR CONDITIONER WARRANTY
Covers manufacturer's air conditioners for 36 months or 36,
000 miles, whichever occurs first. Air conditioner refrigerant charge
is covered for the first 12 months or 12,000 miles, whichever occurs
first. On 1992-96 models, refrigerant is covered only as part of a
warranty repair.
ANTI-CORROSION PERFORATION LIMITED WARRANTY
Covers any body sheet metal panel found to have developed
perforation (rust-through) due to corrosion for 5 years regardless of
mileage. Outer panel coverage extends to 7 years or 100,000 miles,
whichever occurs first, on 1992-96 models.
EMISSION SYSTEM DEFECT WARRANTY (EXCEPT CALIFORNIA)
Warrants that the vehicle was designed, built and equipped to
conform at the time of sale with all applicable U.S. emission
standards. Covers any repairs needed to correct defects in materials
or workmanship which would cause the vehicle not to meet these
standards for 5 years or 50,000 miles, whichever occurs first.
EMISSION SYSTEM PERFORMANCE WARRANTY (EXCEPT CALIFORNIA)
Covers all repairs, adjustments, or replacements if vehicle
has been maintained in accordance with the prescribed scheduled
maintenance instructions and fails to conform to applicable emission
standards and such failure results or will result in the vehicle owner
having to bear any penalty or other sanctions under local, state or

Courtesy of Mitsubishi Motor Sales of America.
2) Disconnect air intake hose and vacuum hoses. Remove air
hose and air outlet housing. Remove heat protectors. Disconnect
exhaust pipe. Remove power steering oil pump and bracket. Remove
engine hanger bracket. Disconnect oil inlet pipe.
3) Disconnect coolant hose and tubes. Remove nuts and bolts
securing exhaust manifold. Remove exhaust manifold and gaskets.
Disconnect oil return pipe. Remove turbocharger assembly.
Removal (Stealth & 3000GT Front)
1) Disconnect negative battery cable. Drain engine oil and
coolant. Remove radiator. Disconnect exhaust pipe. Remove air intake
hose, air hoses and air pipe. Remove alternator and belt. Remove oil
dipstick guide.
2) Remove heat protector. Disconnect oxygen sensor electrical
connector. Remove oil return pipe. Remove turbocharger support bracket
and remove turbocharger from exhaust manifold. See Fig. 10.
Fig. 10: Removing Front Turbocharger (Stealth & 3000GT)
Courtesy of Mitsubishi Motor Sales of America.
Removal (Stealth & 3000GT Rear)
1) Disconnect battery cables and remove battery. Drain engine
oil and coolant. Remove accelerator cable. Remove air hose, air pipe
and heat protectors. Disconnect clutch booster vacuum hose. Remove air

touching a metal ground point on the vehicle prior to
servicing any ESD sensitive component.
ENGINE OIL
CAUTION: Never use non-detergent or straight mineral oil.
FUEL SYSTEM SERVICE
WARNING: Relieve fuel system pressure prior to servicing any fuel
system component (fuel injection models).
HALOGEN BULBS
Halogen bulbs contain pressurized gas which may explode if
overheated. DO NOT touch glass portion of bulb with bare hands. Eye
protection should be worn when handling or working around halogen
bulbs.
POWER STEERING FLUID
When adding power steering fluid, avoid spilling. Damage to
alternator, located beneath power steering reservoir, could result.
RADIATOR CAP
CAUTION: Always disconnect the fan motor when working near the
radiator fan. The fan is temperature controlled and could
start at any time even when the ignition key is in the OFF
position. DO NOT loosen or remove radiator cap when cooling
system is hot.
RADIATOR FAN
WARNING: Keep hands away from radiator fan. Fan is controlled by a
thermostatic switch which may come on or run for up to 15
minutes even after engine is turned off.
SERVICE POINT LOCATIONS
Fig. 1: Service Point Locations (1987-91 2.6L 4-Cylinder Engine)
Courtesy of Mitsubishi Motor Sales of America.