1998 MITSUBISHI MONTERO air bleeding

ANTI-LOCK BRAKE SAFETY PRECAUTIONS
1998 Mitsubishi Montero
GENERAL INFORMATION
Anti-Lock Brake Safety Precautions
* PLEASE READ THIS FIRST *
This article is intended for general information purposes
only. This information may not apply to all makes and models. If
vehicle is equipped with Anti-Lock Brake System (ABS), refer to
appropriate ANTI-LOCK BRAKE SYSTEM article in the BRAKES section for
description, operation, depressurizing, testing, system bleeding,
trouble shooting and servicing of specific system.
WARNING: Failure to depressurize ABS could lead to physical injury.
ANTI-LOCK BRAKE SAFETY PRECAUTIONS
WARNING: Failure to depressurize ABS could lead to physical injury.
* NEVER open a bleeder valve or loosen a hydraulic line
while ABS is pressurized.
* NEVER disconnect or reconnect any electrical connectors
while ignition is on. Damage to ABS control unit may result.
* DO NOT attempt to bleed hyudarulic system without first
referring to the appropriate ANTI-LOCK BRAKE SYSTEM article
in the BRAKES section.
* Only use specially designed brake hoses/lines on ABS equipped
vehicles.
* DO NOT tap on speed sensor components (sensor, sensor rings).
Sensor rings must be pressed into hubs, NOT hammered into
hubs. Striking these components can cause demagnetization or
a loss of polarization, affecting the accuracy of the speed
signal returning to the ABS control unit.
* DO NOT mix tire sizes. Increasing the width, as long as tires
remain close to the original diameter, is acceptable. Rolling
diameter must be identical for all 4 tires. Some
manufacturers recommend tires of the same brand, style and
type. Failure to follow this precaution may cause inaccurate
wheel speed readings.
* DO NOT contaminate speed sensor components with grease. Only
use recommended coating, when system calls for an
anti-corrosion coating.
* When speed sensor components have been removed, ALWAYS check
sensor-to-ring air gaps when applicable. These specifications
can be found in each appropriate article.
* ONLY use rocommended brake fluids. DO NOT use silicone brake
fluids in an ABS equipped vehicle.
* When instlling transmittion devices (CB's, telephones, etc.)
on ABS equipped vehicles, DO NOT locate the antenna near the
ABS control unit (or any control unit).
* Disconnect all on-board computers, when using electric
welding equipment.
* DO NOT expose the ABS control unit to prolonged periods of
high heat (185
F/85C for 2 hours is generally considered a
maximum limit).

ANTI-LOCK BRAKE SYSTEM
1998 Mitsubishi Montero
1997-98 BRAKES
Mitsubishi - Anti-Lock
Montero
DESCRIPTION
CAUTION: See ANTI-LOCK BRAKE SAFETY PRECAUTIONS article in GENERAL
INFORMATION.
NOTE: For more information on brake system, see BRAKE SYSTEM
article.
The Anti-Lock Brake System (ABS) is designed to prevent wheel\
lock-up during heavy braking. This allows operator to maintain
steering control while stopping vehicle in shortest distance possible.
Major components are a hydraulic unit, wheel speed sensors, "G"
sensor, ABS Electronic Control Unit (ECU) and ANTI-LOCK warning light.\
ABS has a self-diagnostic system to indicate a system malfunction and
for use in system trouble shooting.
OPERATION
Each wheel sensor sends an AC electrical signal to the ECU.
The ECU reads this information as wheel speed. When any decelerating
wheel speed rate is determined to be excessive in comparison to other
monitored wheels, the hydraulic unit cycles hydraulic brake pressure
to each wheel to equalize speed of all wheels. ABS turns itself off
when vehicle drops to 4 MPH. Minor lock-up may occur at this point.
With engine running and vehicle speed greater than 4 MPH,
pump motor will operate for a short period of time and may be heard
inside vehicle. During pump motor operation, ABS system is completing
a self-check. During ABS system operation, a pulsing brake pedal and
vibration in steering wheel and vehicle body may be experienced. These
conditions are normal.
BLEEDING BRAKE SYSTEM
BLEEDING PROCEDURES
CAUTION: When adding brake fluid, ensure filter is properly fitted on
reservoir tank.
ABS system is bled using conventional method. With engine
running, manually bleed system using an assistant. For bleeding order,
see BRAKE LINE BLEEDING SEQUENCE table. Ensure Load Sensing
Proportioning Valve (LSPV) is bled in sequence. Remove all air from
brake system. Refill brake fluid reservoir after bleeding procedure is
complete.
BRAKE LINE BLEEDING SEQUENCE









\









\









\









\









\









\









\







Application Sequence
Montero ....................................... RR, LR, LSPV, RF, LF









\









\









\









\









\









\









\

BRAKE SYSTEM
1998 Mitsubishi Montero
1997-98 BRAKES
Mitsubishi - Disc & Drum
Diamante, Eclipse, Galant, Mirage, Montero, Montero Sport,
3000GT
INTRODUCTION
This article contains information on repair and service of
basic hydraulic brake system. If vehicle is equipped with anti-lock
brakes, also see appropriate ANTI-LOCK article.
DESCRIPTION
Brake system consists of a master cylinder, vacuum power
brake booster, proportioning valve and self-adjusting assembly.
Montero has a Load-Sensing Proportioning Valve (LSPV). All models are
equipped with front disc brakes and either rear disc or drum brakes.
Parking brake assembly activates rear brakes.
BLEEDING BRAKE SYSTEM
BLEEDING PROCEDURES
Bleed brakes whenever hydraulic lines are opened or pedal
feels spongy. Bleed system in appropriate sequence. See
BRAKE LINE BLEEDING SEQUENCE table. Use only DOT 3 or DOT 4 approved
fluid and DO NOT mix fluid types.
BRAKE LINE BLEEDING SEQUENCE









\









\









\









\









\









\









\







Application Sequence
Diamante, Eclipse, Galant,
Mirage & 3000GT .................................... RR, LF, LR, RF
Montero ....................................... RR, LR, LSPV, RF, LF
Montero Sport ....................................... RR, LR, RF, LF









\









\









\









\









\









\









\







ADJUSTMENTS
BRAKE PEDAL HEIGHT, FREE PLAY & CLEARANCE
1) To measure brake pedal height, pull up carpet under brake
pedal. Measure distance between floor board and middle of brake pedal
pad surface with brake pedal released. See BRAKE PEDAL HEIGHT
SPECIFICATIONS table.
2) To adjust pedal height, separate connector from stoplight
switch, and loosen switch lock nut. Back-off switch so it does not
contact brake pedal arm. Loosen master cylinder push rod lock nut.
Adjust brake pedal height by rotating master cylinder push rod until
brake pedal height is within specification.
BRAKE PEDAL HEIGHT SPECIFICATIONS









\









\









\









\









\









\









\







Application Pedal Height: In. (mm)\

POWER BRAKE BOOSTER
System Check
1) Run engine for 1-2 minutes. Shut engine off, and depress
brake pedal several times with normal pressure. If pedal height
gradually becomes higher with successive applications, power brake
booster is okay. If pedal height remains steady, power brake booster
is not operating properly, go to next step.
2) With engine stopped, depress brake pedal repeatedly until
pedal height no longer falls. Hold brake pedal down, and start engine.
If pedal moves downward slightly, power brake booster is okay. If
pedal height does not change, power brake booster is not operating
properly, go to next step.
3) With engine running, press and hold brake pedal. Shut off
engine. Hold brake pedal for 30 seconds. Brake pedal height should not
change. If pedal rises, power brake booster is not operating properly,
go to next step.
4) If brake booster operation is not as specified in each
step, disconnect vacuum hose at brake booster and check for sufficient
vacuum with engine running. Also check brake booster check valve
operation. Repair or replace as necessary.
Check Valve Inspection
Remove vacuum hose from power brake booster. Do not remove
check valve from hose. Check valve should hold vacuum in one direction
and allow air to pass in other direction.
LOAD-SENSING PROPORTIONING VALVE (LSPV)
Montero
1) Before diagnosing Load-Sensing Proportioning Valve (LSPV)\
,
ensure all other brake components are operating properly. When all
other brake system components are determined to be okay, ensure LSPV
spring length is within specification. See Fig. 1. See LOAD-SENSING
PROPORTIONING VALVE (LSPV) under ADJUSTMENTS.
2) After spring length is determined to be within
specification, connect pressure gauges to input and output ports of
LSPV. See Fig. 7. Bleed brake system. See BLEEDING BRAKE SYSTEM.
Fig. 7: Connecting Pressure Gauges To LSPV (Montero)
Courtesy of Mitsubishi Motor Sales of America.
3) With vehicle unloaded at correct ride height and LSPV
spring correctly adjusted to 8.9" (227 mm), slowly depress brake pedal\

Removal & Installation
1) Drain master cylinder. Remove cotter pin, washer and
clevis pin. Disconnect push rod from clutch pedal. Remove and plug
hydraulic line at clutch master cylinder.
2) Remove retaining nuts, clutch master cylinder and gasket.
To install, reverse removal procedure. Apply grease to clevis pin
before installing. Fill reservoir and bleed clutch system. See
BLEEDING CLUTCH HYDRAULIC SYSTEM .
CLUTCH RELEASE CYLINDER
Removal & Installation
Remove and plug hydraulic line at release cylinder. Remove
cylinder-to-transmission bolts. Remove clutch release cylinder. To
install, reverse removal procedure. Apply grease to push rod-to-
release fork contact area. Bleed clutch system. See
BLEEDING CLUTCH HYDRAULIC SYSTEM .
BLEEDING CLUTCH HYDRAULIC SYSTEM
Attach hose to bleeder fitting located on clutch release
cylinder, next to hydraulic line. Submerge other end of hose in
container half full of clean brake fluid. Fill reservoir with brake
fluid. Open bleeder fitting. Have assistant press clutch pedal to full
release position. Close bleeder fitting. Release clutch pedal. Repeat
until air bubbles no longer emerge from hose. Refill reservoir.
OVERHAUL
CLUTCH MASTER CYLINDER
NOTE: DO NOT disassemble piston assembly.
Disassembly
Remove piston stop ring, damper and push rod assembly. See
Fig. 6 . Remove piston assembly. Note position of reservoir band for
reassembly reference. Remove reservoir.
Inspection & Reassembly
Inspect components for corrosion, scoring or damage. Replace
if necessary. Apply brake fluid to components during reassembly. On
Montero, adjust clutch master cylinder push rod to 5.90" (150 mm). On
Montero Sport, push rod adjustment is correct after adjusting clutch
pedal free play and pedal height. See CLUTCH PEDAL FREE PLAY and
CLUTCH PEDAL HEIGHT under ADJUSTMENTS. To reassemble, reverse
disassembly procedure. Ensure piston moves freely in bore.
Fig. 6: Exploded View Of Clutch Master Cylinder (Typical)
Courtesy of Mitsubishi Motor Sales of America.

pressure regulator diaphragm opens relief valve, allowing pressure to
bleed off through fuel return line, reducing fuel pressure.
As engine manifold vacuum decreases (open throttle), fuel
pressure regulator diaphragm closes valve, preventing pressure from
bleeding off through fuel return line, increasing fuel pressure.
FUEL CONTROL
Fuel Injectors
Fuel is supplied to engine through electronically pulsed
(timed) injector valves located on fuel rail(s). PCM controls amount\
of fuel metered through injectors based on information received from
sensors.
IDLE SPEED
Air Conditioning (A/C) Relay
When A/C is turned on with engine at idle, PCM signals IAC
motor to increase idle speed. To prevent A/C compressor from switching
on before idle speed has increased, PCM momentarily opens A/C relay
circuit.
Idle Air Control (IAC) Motor
Motor controls pintle-type air valve to regulate volume of
intake air at idle.
During start mode, PCM controls idle intake air volume
according to Engine Coolant Temperature (ECT) sensor input. After
starting, with idle position switch activated (throttle closed), fast
idle speed is controlled by IAC motor and fast idle air control valve
(if equipped).
When idle switch is deactivated (throttle open), IAC motor
moves to a preset position in accordance with ECT sensor input.
PCM signals IAC motor to increase engine RPM in the following
situations: A/T (if applicable) is shifted from Neutral to Drive, A/C
is turned on, or power steering pressure reaches a preset value.
IGNITION SYSTEMS
DIRECT IGNITION SYSTEM (DIS)
Depending on number of cylinders, ignition system is a 2 or
3-coil, distributorless ignition system. On Eclipse (Turbo) and DOHC
V6 engines, Camshaft Position (CMP) sensor is located beside camshaft,\
in front of engine. On all other engines equipped with DIS, CMP sensor
is a separate unit mounted in place of distributor. On DOHC 4-
cylinder, DOHC V6 and 1.8L 4-cylinder engines with California
emissions, Crankshaft Position (CKP) sensor is located beside
crankshaft, in front of engine. PCM determines TDC based on pulse
signals received from sensors and then controls MFI and ignition
timing.
Power Transistors & Ignition Coils
Based on crankshaft position and CMP sensor inputs, PCM
controls timing and directly activates each power transistor to fire
coils. On 4-cylinder engines, power transistor "A" controls primary
current of ignition coil "A" to fire spark plugs on cylinders No. 1
and No. 4 at the same time. Power transistor "B" controls primary
current of ignition coil "B" to fire spark plugs on cylinders No. 2
and No. 3 at the same time. On V6 engines, companion cylinders No. 1
and 4, 2 and 5, and 3 and 6 are fired together.
On all models, although each coil fires 2 plugs at the same
time, ignition takes place in only one cylinder, since the other

HYDRAULIC SYSTEM PRESSURE TEST
1) Disconnect pressure hose from power steering pump. Attach
Pressure Gauge (MB990662-01) and Adapters (MB990993-01 and MB990994-
01). See Fig. 2. Tighten fittings to 22-29 ft. lbs. (30-39 N.m).
2) Bleed system. See HYDRAULIC SYSTEM BLEEDING under
LUBRICATION . Turn wheel several times to bleed air from gauge. Start
engine and let idle. Place thermometer in reservoir. Check fluid
level. Add fluid as necessary.
3) When fluid temperature reaches 122-140
F (50-60C), check
pressure. See POWER STEERING PUMP PRESSURE SPECIFICATIONS table.
Reinstall pressure hose. Do not twist hose or let hose interfere with
adjacent parts. Replace power steering pump if pressure is not within
specification. Bleed system.
CAUTION: DO NOT keep shutoff valve closed more than 3 seconds at a
time. DO NOT keep steering wheel turned to full lock
position for more than 10 seconds at a time.
POWER STEERING PUMP PRESSURE SPECIFICATIONS









\









\









\









\









\









\









\







Application psi (kg/cm)
Valve Closed Or Wheel At Full Lock ............... 1204-1305 (83-90)\
Valve Open (Standard) ............................... 114-142 (8-10\
)









\









\









\









\









\









\









\







Fig. 2: Connecting Pressure Gauge & Shutoff Valve
Courtesy of Mitsubishi Motor Sales of America.
P/S PRESSURE SWITCH

1) Disconnect pressure hose from power steering pump. Attach
Pressure Gauge (MB990662-01) and Adapters (MB990993-01 and MB990994-
01). See Fig. 2. Tighten fittings to 22-29 ft. lbs. (30-39 N.m).
2) Bleed system. See HYDRAULIC SYSTEM BLEEDING under
LUBRICATION . Turn wheel several times to bleed air from gauge. Start
engine and let idle. Place thermometer in reservoir. Check fluid
level. Add fluid as necessary.
3) When fluid temperature reaches 122-140
F (50-60C),
disconnect connector from P/S pressure switch. Connect ohmmeter across
switch terminals. Slowly close shut-off valve. Check pressure when
ohmmeter indicates switch has closed (continuity). Pressure should be
218-290 (15-20 N.m). Slowly open shut-off valve. Check pressure when
ohmmeter indicates switch has opened (no continuity). Pressure should
be 102-174 (7-12 N.m). Reinstall pressure hose. Do not twist hose or
let hose interfere with adjacent parts. Replace P/S pressure switch if
pressure is not within specification. Bleed system.
CAUTION: DO NOT keep shutoff valve closed more than 3 seconds at a
time. DO NOT keep steering wheel turned to full lock
position for more than 10 seconds at a time.
STEERING WHEEL TURNING FORCE
Stationary Test
1) Position vehicle on level surface. Place steering wheel in
straight-ahead position. Start engine and let idle. Using a spring
scale, measure steering wheel turning force clockwise and
counterclockwise.
2) On Montero, turning force should be 8.2 lbs. (3.7 kg) or
less. On Montero Sport, turning force should be 8.8 lbs. (3.9 kg) or
less. If turning force exceeds specification, check for loose or
damaged belt, insufficient fluid, air in power steering fluid, and
collapsed or twisted hoses. Repair or replace as necessary.
REMOVAL & INSTALLATION
IDLER ARM
Removal
Loosen relay rod-to-idler arm lock nut. Using Steering
Linkage Puller (MB991113 or MB990635), separate idler arm from relay
rod and remove relay rod-to-idler arm lock nut. Remove idler arm bolts
and nuts. Remove idler arm. On Montero, loosen, but DO NOT remove
idler arm-to-bracket nut. Press arm from bracket and remove nut and
arm.
Inspection
Check idler arm bushings for damage or wear. Check idler arm
ball stud for looseness.
Installation
1) Apply multipurpose grease to inside surface of bushing and
idler arm support shaft. Insert bushing in idler arm. Insert idler arm
support in idler arm.
2) Install washer (knurled side toward bushing) and NEW lock\
nut. Tighten lock nut to specification. See TORQUE SPECIFICATIONS.
Place idler arm assembly in vise. Using a spring gauge, measure
turning resistance.
3) On all models, turning resistance should be 3-18 INCH lbs.
(.3-2.0 N.m). On Montero, if turning resistance is not within
specification, loosen or tighten lock nut to obtain proper resistance.
4) Install idler arm bolts and nuts. Install relay rod-to-