weight DAEWOO MATIZ 2003 Service Repair Manual

1B – 2 SOHC ENGINE MECANICAL
DAEWOO M-150 BL2
DESCRIPTION AND OPERATION
ENGINE TYPE
The engine is 4-cycle, water-cooled, in-line 3 cylinders
with displacement of 796cc (68.5×72.0mm) (2.70×
2.83 in.).
Engine model
(Specifications)F8C Type SOHC /
2 Valve (MPI)
Maximum power (kw/rpm)37.5 / 6,000
Maximum torque (N
m/rpm)68.6 / 4,600
Compression ratio9.3 : 1
D102B001
ENGINE LUBRICATION
The engine lubrication is of the wetsump method to draw
up the oil forced by the oil pump. The oil pump is of a
trochoid type, and mounted on crankshaft at crankshaft
pulley side (a). Oil is drawn up through oil pump pickup
tube (b) and passed through pump (c) to oil filter (d). The
filtered oil flows into two paths in engine block. In one
path (e), oil reaches crankshaft journal bearings. Oil
from crankshaft journal bearings is supplied to connect-
ing rod bearings by means of intersecting passages
drilled in crankshaft, and then injected from a small hole
provided on big end of connecting rod to lubricate piston
(f), rings, and cylinder wall. In another path (g), oil goes
up to cylinder head and lubricates rocker arm (i), valve
(j), camshaft (k), etc. through the oil hole provided on the
rocker arm shaft (h).
D102B002
CYLINDER HEAD AND VALVE TRAIN
The cylinder head is made of cast aluminum alloy for
better strength in hardness with lightweight, and cam-
shaft (k) and rocker arm shaft (h) arranged in-line sup-
port.
D102B003
The combustion chambers are formed into the manifold
combustion chambers with increased squish parts for
better combustion efficiency and its intake and exhaust

1D – 2 ENGINE COOLING
DAEWOO M-150 BL2
DESCRIPTION AND OPERATION
GENERAL DESCRIPTION
The cooling system maintains the engine temperature at
an efficient level during all engine operating conditions.
When the engine is cold the cooling system cools the
engine slowly or not at all. This slow cooling of the en-
gine allows the engine to warm up quickly.
The cooling system includes a radiator(a) and cooling
fan(b), a thermostat and housing(c), a coolant pump(d),
a coolant pump drive belt and coolant hose. The timing
belt drives the coolant pump.
All components must function properly in order for the
cooling system to operate. The coolant pump draws the
coolant from the radiator. The coolant then circulates
through water jackets in the engine block and the cylin-
der head, distributor case(e), throttle body(f). When the
coolant reaches the operating temperature of the ther-
mostat, the thermostat opens. The coolant then goes
back to the radiator where it cools.
This system directs some coolant through the hoses to
the heater core(g). This provides for heating and de-
frosting. The surge tank(h) is connected to the radiator
and throttle body to recover the coolant displaced by ex-
pansion from the high temperatures. The surge tank
maintains the correct coolant level.
The cooling system for this vehicle has no radiator cap
and drain cock. The coolant is added to the cooling sys-tem through the surge tank. To drain the cooling system,
disconnect the lower radiator hose and drain the cool-
ant.
RADIATOR
This vehicle has a lightweight tube-and-fin aluminum ra-
diator.
SURGE TANK
The surge tank is a transparent plastic reservoir, similar
to the windshield washer reservoir.
The surge tank is connected to the radiator and throttle
body by a hose. As the vehicle is driven, the engine cool-
ant heats and expands. The portion of the engine cool-
ant displaced by this expansion flows from the radiator
into the surge tank. The air trapped in the radiator is de-
gassed into the surge tank.
When the engine is stops, the engine coolant cools and
contracts. The displaced engine coolant is then drawn
back into the radiator. This keeps the radiator filled with
the coolant to the desired level at all times and increases
the cooling efficiency.
Maintain the coolant level between the MIN and the
MAX marks on the surge tank when the system is cold.
D102D001

1F–16 ENGINE CONTROLS
DAEWOO M-150 BL2
the obstruction of the reference air and degrade the O2S
performance.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft
rotational velocity (reference period) variations. The En-
gine Control Module (ECM) determines crankshaft rota-
tional velocity using the Crankshaft Position (CKP)
sensor and the Camshaft Position (CMP) sensor. When
a cylinder misfires, the crankshaft slows down momen-
tarily. By monitoring the CKP and CMP sensor signals,
the ECM can calculate when a misfire occurs.
For a non-catalyst damaging misfire, the diagnostic will
be required to monitor a misfire present for between
1000–3200 engine revolutions.
For catalyst-damaging misfire, the diagnostic will re-
spond to misfire within 200 engine revolutions.
Rough roads may cause false misfire detection. A rough
road will cause torque to be applied to the drive wheels
and drive train. This torque can intermittently decrease
the crankshaft rotational velocity. This may be falsely
detected as a misfire.
A rough road sensor, or “G sensor,” works together with
the misfire detection system. The rough road sensor
produces a voltage that varies along with the intensity of
road vibrations. When the ECM detects a rough road,
the misfire detection system is temporarily disabled.
Misfire Counters
Whenever a cylinder misfires, the misfire diagnostic
counts the misfire and notes the crankshaft position at
the time the misfire occurred. These “misfire counters”
are basically a file on each engine cylinder. A current
and a history misfire counter are maintained for each
cylinder. The misfire current counters (Misfire Current
#1–4) indicate the number of firing events out of the last
200 cylinder firing events which were misfires. The mis-
fire current counter will display real time data without a
misfire DTC stored. The misfire history counters (Misfire
Histtory #1–4) indicate the total number of cylinder firing
events which were misfires. The misfire history counters
will display 0 until the misfire diagnostic has failed and a
DTC P0300 is set. Once the misfire DTC P0300 is set,
the misfire history counters will be updated every 200
cylinder firing events. A misfire counter is maintained for
each cylinder.
If the misfire diagnostic reports a failure, the diagnostic
executive reviews all of the misfire counters before re-
porting a DTC. This way, the diagnostic executive re-
ports the most current information.
When crankshaft rotation is erratic, a misfire condition
will be detected. Because of this erratic condition, the
data that is collected by the diagnostic can sometimes
incorrectly identify which cylinder is misfiring.
Use diagnostic equipment to monitor misfire counter
data on EOBD compliant vehicles. Knowing which spe-
cific cylinder(s) misfired can lead to the root cause, evenwhen dealing with a multiple cylinder misfire. Using the
information in the misfire counters, identify which cylin-
ders are misfiring. If the counters indicate cylinders
numbers 1 and 4 misfired, look for a circuit or compo-
nent common to both cylinders number 1 and 4.
The misfire diagnostic may indicate a fault due to a tem-
porary fault not necessarily caused by a vehicle emis-
sion system malfunction. Examples include the following
items:

Contaminated fuel.

Low fuel.

Fuel-fouled spark plugs.

Basic engine fault.
Fuel Trim System Monitor Diagnostic
Operation
This system monitors the averages of short-term and
long-term fuel trim values. If these fuel trim values stay
at their limits for a calibrated period of time, a malfunc-
tion is indicated. The fuel trim diagnostic compares the
averages of short-term fuel trim values and long-term
fuel trim values to rich and lean thresholds. If either val-
ue is within the thresholds, a pass is recorded. If both
values are outside their thresholds, a rich or lean DTC
will be recorded.
The fuel trim system diagnostic also conducts an intru-
sive test. This test determines if a rich condition is being
caused by excessive fuel vapor from the controlled char-
coal canister. In order to meet EOBD requirements, the
control module uses weighted fuel trim cells to deter-
mine the need to set a fuel trim DTC. A fuel trim DTC
can only be set if fuel trim counts in the weighted fuel
trim cells exceed specifications. This means that the ve-
hicle could have a fuel trim problem which is causing a
problem under certain conditions (i.e., engine idle high
due to a small vacuum leak or rough idle due to a large
vacuum leak) while it operates fine at other times. No
fuel trim DTC would set (although an engine idle speed
DTC or HO2S DTC may set). Use a scan tool to observe
fuel trim counts while the problem is occurring.
A fuel trim DTC may be triggered by a number of vehicle
faults. Make use of all information available (other DTCs
stored, rich or lean condition, etc.) when diagnosing a
fuel trim fault.
Fuel Trim Cell Diagnostic Weights
No fuel trim DTC will set regardless of the fuel trim
counts in cell 0 unless the fuel trim counts in the
weighted cells are also outside specifications. This
means that the vehicle could have a fuel trim problem
which is causing a problem under certain conditions (i.e.
engine idle high due to a small vacuum leak or rough
due to a large vacuum leak) while it operates fine at oth-
er times. No fuel trim DTC would set (although an en-
gine idle speed DTC or HO2S DTC may set). Use a
scan tool to observe fuel trim counts while the problem is
occurring.

ENGINE CONTROLS 1F–247
DAEWOO M-150 BL2

Excessive engine overloading. Check for seized pul-
leys, pumps, or motors on the accessory drive,
Overweight engine oil.
DTC P0505 Idle Air Control Valve (IACV) Circuit Fault
StepActionValue(s)YesNo
1
Perform an On-Board Diagnostic (EOBD) System
Check.
Was the check performed?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Install a scan tool to the Data Link Connector
(DLC).
2. Operate the engine to idle speed.
3. Transmission in park or neutral and the parking
brake set.
4. A/C is off.
5. Using scan tool, command the Idle Air Control
(IAC) valve up and down between the specified
value.
Does the rpm change smoothly when he
commanded by the scan tool?
900–1200
rpm
Go to Step 3Go to Step 5
3
1. Turn the ignition OFF.
2. Disconnect the IAC valve connector.
3. Measure the resistance between terminal C and
D of the IAC valve.
4. Measure the resistance between terminal B and A
of the IAC valve.
Is the resistance within the specified value?
40–80 ΩGo to Step 4Go to Step 13
4
1. Measure the resistance between terminal D and
B of the IAC valve.
2. Measure the resistance between terminal C and
A of the IAC valve.
Is the resistance equal to the specified value?
∞Go to Step 15Go to Step 13
5
1. Turn the ignition OFF.
2. Disconnect the IAC valve connector.
3. Turn the ignition ON.
4. With test light connected to ground, probe the
IAC connector terminals.
Does the test light illuminate on D terminals?
–
Go to Step 6Go to Step 7
6
With test light connected to B+, probe the IAC
connector terminals.
Does the test light illuminate on D terminals?
–
Go to Step 8Go to Step 9
7
Check for an open or short to ground in the IAC high
and low circuits and repair as needed.
Is the repair complete?
–
Go to Step 15Go to Step 10
8
1. Idle the engine.
2. Connect a test light to ground, probe the IAC
connector terminals.
Does the test light flash On and OFF for all
terminals?
–
Go to Step 11Go to Step 12
9
Check for an open or a short to voltage in the IAC
valve high and low circuits and repair as needed.
Is the repair complete?
–
Go to Step 15Go to Step 10
10
Check the Engine control Module (ECM) connector
for poor connections and repair as needed.
Is the repair complete?
–
Go to Step 15Go to Step 14

2A–2 SUSPENSION DIAGNOSIS
DAEWOO M-150 BL2
Condition Probable Cause Correction
Car Lead/Pull
Mismatched or uneven tires.
Replace the tires.

A broken or a sagging coil spring.
Replace the coil spring.

A improperly radial tire lateral force.
Check the wheel alignment.

Switch the tire and wheel assemblies.

Replace the tires as needed.

The front–wheel alignment is
out–of–align.
Align the front wheels.

Off–center steering gear.
Reseat the pinion valve assembly.

Replace the pinion valve assembly as
needed.

Front–brake dragging.
Adjust the front brakes.
Abnormal or Excessive
Tire Wear
The front–wheel and rear–wheel
alignment is out–of–align.
Align the front and the rear wheels.

Excessive toe.
Adjust the toe.

A broken or a sagging coil spring.
Replace the coil spring.

Out–of–balance tires.
Balance the tires.

Worn strut dampeners.
Replace the strut dampeners.

A failure to rotate tires.
Rotate the tires.

Replace the tires as needed.

Overloaded vehicle.
Maintain the proper load weight.

Low tire inflation.
Inflate the tires to the proper pressure.
Scuffed Tires
Incorrect toe.
Adjust the toe.

A twisted or a bent suspension arm.
Replace the suspension arm.
Wheel Tramp
An out–of–balance tire or wheel.
Balance the tire or the wheel.

Improper strut dampener action.
Replace the strut dampeners.
Shimmy, Shake, or
An out–of–balance tire or wheel.
Balance the tire or the wheel.
Vibration
Excessive wheel hub runout.
Measure the hub flange runout.

Replace the hub as needed.

Excessive brake drum or brake rotor
imbalance.
Adjust the brakes.

Replace the brake rotor or the brake
drum as needed.

Worn tie rod ends.
Replace the tie rod ends.

Wheel trim imbalance.
Balance the wheel.

A worn ball joint.
Replace the control arm and ball joint
assembly.

Excessive wheel runout.
Measure the wheel runout.

Replace the wheel as needed.

Excessive loaded radial runout on the
tire and wheel assembly.
Match–mount the tire and wheel
assembly.

2A–4 SUSPENSION DIAGNOSIS
DAEWOO M-150 BL2
Condition Probable Cause Correction
Abnormal Noise, Front
A loose stabilizer shaft link.
Tighten the stabilizer shaft link.
Suspension
Loose wheel nuts.
Tighten the wheel nuts.

Loose suspension bolts or nuts.
Tighten the suspension bolts or the
nuts.

Loose wheel covers.
Tighten the wheel covers.

Worn strut dampeners or strut
mountings.
Replace the strut dampeners.

Tighten the strut mounting nuts.

An improperly positioned strut spring.
Adjust the strut spring to the proper
position.
Wander or Poor
Mismatched or uneven tires.
Replace the tires.
Steering Ability
Worn strut dampeners.
Replace the strut dampeners.

A loose stabilizer shaft link.
Tighten the stabilizer shaft link.

A broken or a sagging coil spring.
Replace the coil spring.

The steering preload adjustment is
out–of–adjustment.
Perform a rack bearing preload
on–vehicle adjustment.

The front–wheel and the rear–wheel
alignment are out–of–align.
Align the front and the rear end
wheels.
Erratic Steering when
Worn or loose wheel bearings.
Replace the wheel bearings.
Braking
A broken or a sagging coil spring.
Replace the coil spring.

A leaking caliper.
Replace the caliper.

Warped rotors.
Replace the rotors.

An incorrect or an uneven caster.
If the caster is beyond specifications,
check the frame and repair it as
needed.
Low or Uneven Trim
A broken or a sagging coil spring.
Replace the coil spring.
Height
An overloaded vehicle.
Maintain the proper load weight.

An incorrect or weak coil spring.
Replace the coil spring.
Ride Too Soft
Worn strut dampeners.
Replace the strut dampeners.

A broken or a sagging coil spring.
Replace the coil spring.
Ride Too Harsh
Incorrect strut dampeners.
Replace the strut dampeners.

An incorrect coil spring.
Replace the coil spring.
Body Leans or Sways
A loose stabilizer shaft link.
Tighten the stabilizer shaft link.
in Corners
Worn strut dampeners or strut
mountings.
Replace the strut dampeners.

Tighten the strut assembly mounting
nuts.

an overloaded vehicle.
Maintain the proper load weight.

A broken or a sagging coil spring.
Replace the coil spring.
Suspension Bottoms
Worn strut dampeners.
Replace the strut dampeners.

An overloaded vehicle.
Maintain the proper load weight.

A broken or a sagging coil spring.
Replace the coil spring.

2E –4 TIRES AND WHEELS
DAEWOO M-150 BL2
WHEELS
Wheels must be replaced if they are bent, dented, have
excessive lateral or radial runout, leak air through welds,
have elongated bolt holes, or if the wheel bolts won’t
stay tight or are heavily rusted. Wheels with excessive
runout may cause vehicle vibration. Replacement
wheels must be equivalent to the original equipment
wheels in load capacity, diameter, rim width, offset, and
mounting configuration. A wheel of improper size or type
may affect wheel and bearing life, brake cooling,
speedometer/odometer calibration, vehicle ground
clearance, and tire clearance to the body and the chas-
sis.
INFLATION OF TIRES
The pressure recommended for any vehicle line is care-
fully calculated to give a satisfactory ride, handling,
tread life, and load-carrying capacity.
Tire pressure should be checked monthly or before any
extended trip. Check the tires when they are cold, after
the vehicle has sat for 3 hours or more or has been driv-
en less than 1 mile. Set the tire pressure to the specifi-
cations on the tire label located on the rear face of the
driver’s door. Tire inflation pressure is also given under
“Tire Size and Pressure Specifications” in this section.
Valve caps or extensions should be on the valves to
keep dust and water out.
Higher than recommended tire pressure can cause:

Hard ride

Tire bruising or damage

Rapid tread wear at the center of the tire
Lower than recommended pressure can cause:

Tire squeal on turns

Hard steering

Rapid and uneven wear on the edges of the tread

Tire rim bruises and rupture

Tire cord breakage

High tire temperatures
Unequal tire pressures on same axle can cause:

Uneven braking

Steering lead
Reduced handling

Swerve on acceleration

Torque steer
ROTATION TIRES
Front and rear tires perform different jobs and can wear
differently depending on the tires of road driven, driving
habit, etc.
The front tires will wear faster than the rear ones.
To avoid uneven wear of tires and to prolong tire life, in-
spect and rotate the tires every 5,000 km (3,100 miles).
After rotating the tires, adjust the tire inflation pressures
and be sure to check wheel nuts tightness.
D16A304A
WHEEL BALANCE
Balance is the easiest procedure to perform and should
be done first if the vibration occurs at high speeds, or if
the tires or the wheels are replaced.
When proceeding the wheel balancing procedure regard
the belows.
1. Do not use the wheel weight over two at the inboard
and the outboard flanges.
2. The total weight of the wheel weights should not ex-
ceed the 100 grams (3.5 ounces).
3. Blanching the assemblies with factory aluminum
wheels requires the use of special nylon–coated,
clip–on wheel weights.

TIRES AND WHEELS 2E–7
DAEWOO M-150 BL2
REPAIR INSTRUCTIONS
ON-VEHICLE SERVICE
D106A501
D106A502
WHEEL
Removal Procedure
1. Remove the wheel cover on the vehicle equipped
with steel wheel.
2. Loosen the wheel nuts.
3. Raise and suitably support the vehicle.
4. Remove the wheel nuts.
Notice: Never use heat to loosen a tight wheel. It can
shorten the life of the wheel, the wheel nuts and the
wheel bearings. Excessive force, such as hammering
the wheel or tire, can also cause damage and is not rec-
ommended. Slight tapping of the wheel sidewall with
one’s hand or with a rubber mallet is acceptable.
5. Remove the wheel.
Difficulty in removing the wheels from the vehicle can be
due to foreign material or to a tight fit between the wheel
centerhole and the hub or the rotor. These wheels can
be removed by
1. Retightening the wheel nuts on the affected wheel
and then loosening the wheel nuts by two turns.
2. Lowering the vehicle and rocking it from side to side
as hard as possible, using one or more person’s body
weight to loosen the wheel.
3. Raising the vehicle and removing the wheel.
Caution: Do not allow the penetrating oil to get on
the vertical surfaces between the wheel and the
drum (or rotor) because penetrating oil in this area
could cause the wheel to work loose as the vehicle
is driven, resulting in loss of control and an injury
accident.
Penetrating oil is not effective in removing tight wheels.
If it is used, however, apply it sparingly and only to the
wheel’s centerhole area.

2E –8 TIRES AND WHEELS
DAEWOO M-150 BL2
D16A503A
90–11 0 Nm
Installation Procedure
Notice: Before installing the wheels, remove any build-
up of corrosion on the wheel mounting surface and the
brake drum or the rotor mounting surface by scraping
and brushing them with a wire brush. Installing the
wheels without good metal-to-metal contact at the
mounting surfaces can cause the wheel nuts to loosen,
which can later allow a wheel to come off while the ve-
hicle is moving. Wheel nuts must be tightened in se-
quence and to the proper torque to avoid bending the
wheel, the brake drum or the rotor.
1. Mount the wheel.
2. Install the wheel nuts in the diagonally. Do not tighten
the wheel nuts.
3. Lower the vehicle.
Tighten
Tighten the wheel nuts to 90–110 Nm (66–81 lb-ft).
ON-VEHICLE BALANCING
On-vehicle balancing will help correct vibrations due to
brake drum, rotor, and wheel cover imbalances.
Notice: Do not allow the front suspension to hang free.
When the drive axle is run at an extreme angle, extra
vibrations can occur, as well as damage to seals and
joints.
1. During on-vehicle balancing, do not remove the bal-
ance weights from the off-vehicle dynamic balance.
2. If more than 1 ounce of additional weight is required,
split the weight between the inner and the outer rim
flanges.
3. Spin the driven tire and wheel assemblies using the
engine.
OFF-VEHICLE BALANCING
Perform wheel balancing with an electronic off-vehicle
balancer. The balancer is easy to use and gives both a
static and a dynamic balance. Unlike on-vehicle balanc-
ing, the off-vehicle balancer does not correct for drum or
rotor imbalance. This drawback is overcome by its accu-
racy. Secure the wheel on the balancer with a cone
through the back side of the centerhole, not through the
wheel nut holes.
CORRECTING NON-UNIFORM TIRES
There are two ways to correct properly balanced tires
which still vibrate. One method uses an automatic
machine which loads the tire and buffs small amounts of
rubber from high spots on the outer two tread rows.
Correction by this method is usually permanent and, if it
is done properly, does not significantly affect the
appearance or the tread life of the tire. Tire truing with a
blade-type machine is not recommended because it
substantially reduces the tread life and often does not
correct the problem permanently.

4A –4 HYDRAULIC BRAKES
DAEWOO M-150 BL2
DIAGNOSITIC INFORMATION AND PROCEDURES
BRAKE SYSTEM TESTING
(Left–Hand Drive Shown, Right–Hand
Drive Similar)
Brakes should be tested on a dry, clean, reasonably
smooth and level roadway. A true test of brake perfor-
mance cannot be made if the roadway is wet, greasy, or
covered with loose dirt whereby all tires do not grip the
road equally. Testing will also be adversely affected if the
roadway is crowned so as to throw the weight so roughly
that the wheels tend to bounce.
Test the brakes at different vehicle speeds with both light
and heavy pedal pressure; however, avoid locking the
brakes and sliding the tires. Locked brakes and sliding
tires do not indicate brake efficiency since heavily
braked, but turning, wheels will stop the vehicle in less
distance than locked brakes. More tire-to-road friction is
present with a heavily braked, turning tire than with a
sliding tire.
Because of the high deceleration capability, a firmer
pedal may be felt at higher deceleration levels.
There are three major external conditions that affect
brake performance:

Tires having unequal contact and grip of the road will
cause unequal braking. Tires must be equally in-
flated, and the tread pattern of the right and the left
tires must be approximately equal.

Unequal loading of the vehicle can affect the brake
performance since the most heavily loaded wheels
require more braking power, and thus more braking
effort, than the others.

Misalignment of the wheels, particularly conditions of
excessive camber and caster, will cause the brakes
to pull to one side.
To check for brake fluid leaks, hold constant foot pres-
sure on the pedal with the engine running at idle and the
shift lever in NEUTRAL. If the pedal gradually falls away
with the constant pressure, the hydraulic system may be
leaking. Perform a visual check to confirm any sus-
pected leaks.
Check the master cylinder fluid level. While a slight drop
in the reservoir level results from normal lining wear, an
abnormally low level indicates a leak in the system. The
hydraulic system may be leaking either internally or ex-
ternally. Refer to the procedure below to check the mas-
ter cylinder. Also, the system may appear to pass this
test while still having a slight leak. If the fluid level is nor-
mal, check the vacuum booster pushrod length. If an in-
correct pushrod length is found, adjust or replace the
rod.Check the master cylinder using the following proce-
dure:

Check for a cracked master cylinder casting or brake
fluid leaking around the master cylinder. Leaks are in-
dicated only if there is at least one drop of fluid. A
damp condition is not abnormal.

Check for a binding pedal linkage and for an incorrect
pushrod length. If both of these parts are in satisfac-
tory condition, disassemble the master cylinder and
check for an elongated or swollen primary cylinder or
piston seals. If swollen seals are found, substandard
or contaminated brake fluid should be suspected. If
contaminated brake fluid is found, all the components
should be disassembled and cleaned, and all the rub-
ber components should be replaced. All of the pipes
must also be flushed.
Improper brake fluid, or mineral oil or water in the fluid,
may cause the brake fluid to boil or cause deterioration
of the rubber components. If the primary piston cups in
the master cylinder are swollen, then the rubber parts
have deteriorated. This deterioration may also be evi-
denced by swollen wheel cylinder piston seals on the
drum brake wheels.
If rubber deterioration is evident, disassemble all the hy-
draulic parts and wash the parts with alcohol. Dry these
parts with compressed air before reassembly to keep al-
cohol out of the system. Replace all the rubber parts in
the system, including the hoses. Also, when working on
the brake mechanisms, check for fluid on the linings. If
excessive fluid is found, replace the linings.
If the master cylinder piston seals are in satisfactory
condition, check for leaks or excessive heat conditions.
If these conditions are not found, drain the fluid, flush the
master cylinder with brake fluid, refill the master cylin-
der, and bleed the system. Refer to “Manual Bleeding
the Brakes” in this section.
BRAKE HOSE INSPECTION
The hydraulic brake hoses should be inspected at least
twice a year. The brake hose assembly should be
checked for road hazard damage, cracks, chafing of the
outer cover, and for leaks or blisters. Inspect the hoses
for proper routing and mounting. A brake hose that rubs
on a suspension component will wear and eventually
fail. A light and a mirror may be needed for an adequate
inspection. If any of the above conditions are observed
on the brake hose, adjust or replace the hose as neces-
sary.