Hyundai HD78 User Manual

Brake System

(WABCO ABS)

General

Description ....................................................	BR -3
Components .................................................	BR -14
Dignosis ........................................................	BR -16
On-Vehicle Inspection And Adjustment .......	BR -20
Specifications ...............................................	BR -22

Vacuum Assisted Hydraulic Brake

Brake Pedal
Components............................................	BR -27
Removal ..................................................	BR -28
Installation ...............................................	BR -28
Adjustment ..............................................	BR -28
Brake Booster
Component .............................................	BR -30
Removal ..................................................	BR -31
Installation ...............................................	BR -32
Inspection ................................................	BR -33
Brake Master Cylinder
Components............................................	BR -36
Removal ..................................................	BR -37
Installation ...............................................	BR -38
Load Sensing Proportioning Valve(LSPV)
Components............................................	BR -39
Removal ..................................................	BR -40
Inspection ................................................	BR -40

Front Brake Assembly

Disc Brake
Components............................................	BR -41
Removal ..................................................	BR -42
Installation ...............................................	BR -43
Disassembly............................................	BR -44
Reassembly ............................................	BR -45
Inspection ................................................	BR -46
Drum Brake
Components............................................	BR -48
Removal ..................................................	BR -49
Replacement ...........................................	BR -50
Installation ...............................................	BR -51

Parking Brake System

Components .................................................	BR -52
Removal .......................................................	BR -53
Installation ....................................................	BR -54
Adjustment ....................................................	BR -56

Rear Brake Assembly

Drum Brake
Components............................................	BR -57
Removal ..................................................	BR -58
Replacement ...........................................	BR -59
Installation ...............................................	BR -61
Exhaust Brake
Component Location ..............................	BR -62
Components............................................	BR -63
Replacement ...........................................	BR -67
Disassembly............................................	BR -68
Reassembly ............................................	BR -68
Inspection ................................................	BR -70

ABS(Anti-Lock Brake System)

Specifications ...............................................	BR -72
Description ....................................................	BR -72
Using Blink Code Diagnostics .....................	BR -76
DTC Troubleshooting ...................................	BR -83
Repair Instruction .........................................	BR -88
Connector Configurations ............................	BR -90
Full Circuit Diagram .....................................	BR -91
Inspection .....................................................	BR -91
Adjustment ....................................................	BR -92
ABS Modulator
Removal ..................................................	BR -94
Installation ...............................................	BR -94
Wheel Speed Sensor
Description ..............................................	BR -95
Replacement ...........................................	BR -95
ABS Control Module
Removal ..................................................	BR -97
Installation ...............................................	BR -98
Schematic Diagrams ..............................	BR -99
DTC Chart ...............................................	BR -104
0000 ........................................................	BR -107
0001 ........................................................	BR -110
0002 ........................................................	BR -113
0003 ........................................................	BR -116
0004 ........................................................	BR -119
0009 ........................................................	BR -122
000A ........................................................	BR -125
000B ........................................................	BR -128
000C ........................................................	BR -131
000D ........................................................	BR -134
000E ........................................................	BR -137

000F ........................................................	BR -140	003D ........................................................	BR -233
0010 ........................................................	BR -143	003F ........................................................	BR -235
0011 ........................................................	BR -146	0040 ........................................................	BR -237
0017 ........................................................	BR -149	0041 ........................................................	BR -240
0018 ........................................................	BR -152	0042 ........................................................	BR -243
0019 ........................................................	BR -155	0043 ........................................................	BR -246
001A ........................................................	BR -158	0044 ........................................................	BR -249
001B ........................................................	BR -161	0045 ........................................................	BR -252
001C ........................................................	BR -164	0046 ........................................................	BR -255
001D ........................................................	BR -167	0047 ........................................................	BR -257
001E ........................................................	BR -170	0049 ........................................................	BR -260
001F ........................................................	BR -173	004A ........................................................	BR -263
0020 ........................................................	BR -176	004B ........................................................	BR -266
0021 ........................................................	BR -179	004C ........................................................	BR -269
0022 ........................................................	BR -182	004D ........................................................	BR -272
0023 ........................................................	BR -185	004E ........................................................	BR -275
0024 ........................................................	BR -188	004F ........................................................	BR -278
0029 ........................................................	BR -191	0050 ........................................................	BR -281
002A ........................................................	BR -194	0051 ........................................................	BR -284
002B ........................................................	BR -197	0052 ........................................................	BR -287
002C ........................................................	BR -200	0053 ........................................................	BR -290
002D ........................................................	BR -203	0054 ........................................................	BR -293
002E ........................................................	BR -206	0055 ........................................................	BR -296
002F ........................................................	BR -209	0056 ........................................................	BR -299
0030 ........................................................	BR -212	0057 ........................................................	BR -302
0032 ........................................................	BR -215	0058 ........................................................	BR -305
0033 ........................................................	BR -218	0059 ........................................................	BR -308
0037 ........................................................	BR -221	005A ........................................................	BR -311
0038 ........................................................	BR -223	005B ........................................................	BR -314
0039 ........................................................	BR -225	005C ........................................................	BR -317
003B ........................................................	BR -227	005D ........................................................	BR -320
003C ........................................................	BR -230

General

DESCRIPTION

BRAKE SYSTEM

The service brakes are internally expanding type hydraulic brakes acting on all wheels. The brakes for the front wheels are 2-leading type and those for the rear wheels are duo-servo or dual 2-leading type.

The brake booster gives faster hydraulic pressure buildup. Tandem type brake master cylinder also contributes to safety. The brake pedal, which is easy-to-operate pendant type, transmits depression force via operating rod, etc. to the BRAKE BOOSTER, which boosts it and drives the master cylinder.

The BRAKE BOOSTER vacuum line is equipped with a vacuum tank which minimizes negative pressure change even in the case of repeated and frequent braking operation.

Brake Booster

1.When not in Operation

When not in operation, no force acts on the operating rod and hence the valve plunger is seated on the poppet to open the negative pressure valve and to close the atmospheric valve.

Negative pressure generated by the engine draws out air from the chamber on the left side of the diaphragm plate. And as the chamber on the right side of the diaphragm plate is also evacuated via the vacuum channel and the negative pressure valve that is opened. As a result, the diaphragm plate is pressed tightly onto the rear shell surface by the diaphragm plate return spring. Atmosphere goes through the air filter into space around the operating rod but does not flow further as the atmospheric valve of the valve plunger is closed.

2.When in Operation

When the brake pedal depression force overcomes the valve return spring force, the operating rod, valve plunger and poppet now move to the left and the poppet is pressed tightly onto the valve plunger seat by the poppet spring, closing the negative pressure valve. When the brake pedal is further depressed following closure of this valve, the valve plunger clears the poppet to open the atmospheric valve and atmosphere now flows through the channel into the chamber on the right side of the diaphragm.

This flow of atmosphere produces the pressure difference across the diaphragm and the force resulting from such pressure difference overcomes the piston return spring force. As a result, the

diaphragm pushes the push rod as it moves from right to left. The push rod thus pushes the master cylinder piston, generating high fluid pressure from low pedal depression force.

SUDBR9016L

Brake Master Cylinder

1.Normal Operation

The tandem type brake master cylinder has independent hydraulic systems for front and rear brakes.

Should one of the two hydraulic systems fail, braking by survived system (front or rear wheels) ensures safety. When the brake pedal is depressed, the primary piston is pushed to left, developing hydraulic pressure in the pressure chamber on the primary side. This pressure directly acts on the secondary piston to push the secondary piston to left, developing hydraulic pressure also in the pressure chamber on the secondary side. As a result, each piston pressurizes brake fluid to generate hydraulic pressure in both front and rear brake systems.

SUDBR9017L

2.When fluid leaks are caused in front brake system

In this case, depression of the brake pedal to push the push rod does not develop hydraulic pressure as the brake fluid leaks from the front brake system. Therefore, the primary piston compresses the primary return spring and the retainer pushes the secondary piston, which then pressurizes brake fluid in space between the secondary piston and cylinder body, thus generating hydraulic pressure in the rear brake system only.

SUDBR9018L

3.When fluid leaks are caused in rear brake system

In this case, when the brake pedal is depressed to push out the push rod, the secondary piston end comes into contact with the cylinder body since brake fluid in the rear brake system leaks. When the push rod is further pushed, the primary piston pressurizes brake fluid in the space between the primary and secondary pistons, generating hydraulic pressure in the front brake system only.

Front And Rear Wheel Brakes Front wheel Brakes

The wheel cylinder is so constructed that the piston extends in one direction only to push the shoes which are held down to the backing plate by the shoe hold down pin. The return springs mounted on the shoe fixed and moving sides cause contraction of the shoe and wheel cylinder piston when the brake is released.

When the vehicle is running forward, both shoes work as leading shoes.

EMTBR5004A

When the pedal is depressed, brake fluid supplied under pressure from the master cylinder enters the wheel cylinder, of which piston moves the shoe moving side so that the lining is pressed against the drum inside. Resultant friction between the lining and drum causes the shoe to try to turn with the drum, thus boosting the braking force.

EMTBR5005A

Rear Wheel Brake Dual 2-leading Brake

The wheel cylinders are installed at front and rear and the pistons extend in both upward and downward directions to push the shoes from both directions. The shoes are held down to the backing plate by shoe hold down pins and the return springs mounted on the shoes causing contraction of the shoe and wheel cylinder piston when the brake is released. During both forward and reverse operation of the vehicle, the shoes work as leading shoes.

EMTBR5004A

When the pedal is depressed, brake fluid supplied under pressure from the master cylinder enters the wheel cylinder, of which piston causes the shoe to expand in both directions to press the lining against the drum inside. Resultant friction between the lining and drum causes the shoe to try to turn with the drum, thus boosting the braking force.

EMTBR5006A

Wheel Cylinder

The wheel cylinder driven by hydraulic pressure generated by the brake master cylinder presses the shoe (lining) against the brake drum.

There are following two types of wheel cylinder according to the method of pushing the shoe.

EMTBR5007A

1.2-leading type : Front brake

In pedaling brake, oil pressure rising is master cylinder goes into wheel cylinder and pushes piston. Shoe contacting with the end of piston sticks to brake drum and generates frictional force.

EMTBR5008A

2. Dual 2-leading type : rear brake

EMTBR5009A

Brake Fluid Level Sensor

The brake fluid level sensor installed in the brake fluid tank senses the brake fluid level in the tank. When the fluid level drops to a preset level, the sensor operates to turn on the warning lamp in the cluster to warn low brake fluid level.

EMTBR5010A

Exhaust Brake

SUDBRA015L

The exhaust brake system, as an assistant function of the service brake, comprises of the exhaust brake device installed at the middle portion of the exhaust pipe and the intake shutter installed at the intake manipulate to reduce the intake air noise.

When the exhaust brake device close the butterfly valve, the pressure inside of the pipe increases. This increased pressure influences to the piston to get the braking force. At that time, the intake shutter is also closed. When the clutch pedal, the accelerator pedal or the exhaust brake switch is released, the electric circuit is OFF and the exhaust brake is released.

The exhaust brake is the vacuum type assistant device which uses the negative pressure.

Intake Shutter

When the exhaust brake is operating, the intake shutter(A) reduces the amount of the intake air through the intake manipulate so as that the exhaust pressure is operated to the piston effectively. As a result, the noise will be reduced and the brake will be more effective.

KMTBR5513A

Exhaust Brake Unit

1.At Working

If the exhaust brake switch is ON, the three-way magnetic valve is opened. The vacuum pressure of the vacuum tank is applied to the exhaust brake unit so as to pull the piston.

As a result, the butterfly valve linked to the push rod is closed so that the exhaust brake is working.

EMTBR5012A

2.At releasing

If the exhaust brake switch, the clutch switch and the accelerator switch are OFF, the 3-way magnetic valve closes the circuit to the vacuum tank and opens the atmosphere circuit.

Therefore, the atmospheric pressure is applied to the exhaust brake unit. Due to the spring tension, the butterfly valve is opened. The exhaust brake is released.

EMTBR5013A

The 3-way Magnetic Valve

1.At working

If the exhaust brake switch is ON, an electric current will flow through the coil and then a magnetic field is formed. The magnetic force pulls the plunge to upward. At that time, the valve seat at the plunger closes the way to the atmosphere pressure while it opens the way linking the vacuum tank and the brake chamber.

EMTBR5014A

2.At releasing

If the exhaust brake switch is OFF, the electric current flowing through the coil is shut down. Due to the spring tension, the plunger will be pushed so as to close the way to vacuum tank while the way to the atmosphere pressure and the brake chamber.

EMTBR5060A

LOAD SENSING PROPORTIONING VALVE

SUDBRA021L

1.	LSPV assembly	4.	Lever assembly	7.	Adjusting nut
2.	Bleeder screw	5.	Sensor spring	8.	Operating lever
3.	Bracket	6.	Spring guide	9.	Connecting link assembly

Construction

LSPV is consist of sensor part and pressure controller part.

1.Sensor part

It consists of spring, operating lever, link. It senses the height of vehicle with varying according to the amount loads

2.Pressure controller part

It consists of valve stem mechanism for proportioning control of sensor force.

EMTBR5016A

Operating Principle

LSPV body is mounted in the frame and the end of the link is mounted in the rear axle. With varying of amount of vehicle load changes the relative position of frame and rear axle, so sensor spring force varies to the valve stem. It controls the rear axle brake fluid pressure.

1.Unloaded status

The sensor spring presses the valve stem slightly, so the brake fluid pressure is set weakly.

2.Loaded status

The sensor spring presses the valve stem strongly, so the brake fluid pressure is set highly.

NOTICE

Don't loose or don't retighten the adjusting nut crimping.

SUDBR9036L

Service and Inspection of the LSPV

Check the LSPV as below when replace the sensor spring, valve body assembly or reinstall the rear axle, rear spring.

Symptom	Probable Cause	Remedy
Braking force is i-	Insufficient air bl-	Air bleeding
nsufficient.	eeding
	Maladjusted sen-	Readjust
	sor spring
	Sensor spring br-	Replace valve a-
	oken	ssembly
	Oil leakage in the	Tighten brake flu-
	brake fluid line or	id line or replace
	LSPV assembly	LSPV assembly
Rear brake is loc-	Maladjusted sen-	Readjust
k too fast.	sor spring
	Inner fault the L-	Replace LSPV a-
	SPV	ssembly

PARKING BRAKE GENERAL

SUDBRA022L

1.Parking brake lever assembly

2.Cam lever

3.Parking brake drum

4.Adjusting nut

5.Parking brake cable

The parking brake installed behind the transmission is an internal expansion type acting on the propeller shaft.

It controls propeller shaft rotation to work as a parking brake.

The control is wire mechanical type; brake shoes are pressed via a wire to control the propeller shaft.

Parking Brake Proper

When the lever at the driver's seat is pulled, the cam lever is actuated via a wire cable and resultant cam rotation causes the brake shoes to expand and be forced against the brake drum. The braking force is thus obtained by friction between the shoes and drum. When the lever is released, the cam lever returns to the initial position and the braking force is released by the brake shoe return springs.

EMTBR5019A

COMPONENTS(LHD)

SUDBRA001L

1.Vacuum tank

2.Vacuum hose

3.Brake booster

4.Master cylinder

5.Reservoir tank

6.A.B.S modulator

COMPONENTS(RHD)

SUDBRA002L

1.Brake booster

2.Master cylinder

3.Brake pedal

4.Parking brake lever

5.Vacuum tank

6.Exhaust brake

7.ABS HECU(Hydraulic Electrical Control Unit)

Diagnosis

Symptom		Causes	Remedy	Remark
Irregular Braking		The air pressures of tire are different.	Adjust the air pressure of tire.
Force
		The sizes of the right and left tires are different	Replace the tire.
		.
		The adjustment of the wheel bearing is defecti-	Adjust (Check the wheel bearing)
		ve.
		The sizes of the right and left wheel bases are	Check and adjust the loosening the U-b-
		different.	olt or damages on center bolt.
		The wheel alignment is defective.	Adjust
After releasing t-		The vertical surface of the back plate is rough.	Replace the back plate or check the lini-
he brake	pedal,		ng.
the braking force
		The operation of the wheel cylinder is defective	Check the contacting, the piston cup and
is release too la-		.	wearing status. If needed, replace it. Ch-
te.			eck the lining.
		The return spring is damaged.	Replace the spring.
Unbalance at th-		The surface of the lining is contaminated by th-	If it is contaminated by oil or grease, the-
e right and left			n replace it. If it is contaminated by water
braking force		e oil, grease or water.	, dry it.
		The lining is defective or The material of lining	Replace or adjust.
		is improper.
		The wear is irregular. The surface is rough.	Replace the lining. Check the inside of t-
			he drum, if needed, replace it.
		The lining contact is defective.	Adjust the lining with being installed.
		The brake drum is worn irregularly.	Adjust or replace it.
Unstable brakin-		The brake drum is deformed.	Replace
g force
		The back plate is deformed or loosened. The	If it is loosened, tighten with specified to-
		vertical surface of it is rough.	rque. Otherwise, replace it.
Improper	Lock	The drum is worn.	Adjust or Replace	Drum	limit
Point				STD
				+
				: Dia	2m-
				m
		The lining is worn irregularly.	Adjust
		The lining contact is defective.	Adjust with being installed.
			(Temperature of lining should be less th-
			°
			an 100 C)

Symptom	Causes		Remedy	Remark
Low Braking Fo-	The clearance between the brake pedal and fl-		Refer to the item for decreasing the clea-
rce	oor is 45mm or more. (at Pressure-600mmHg,
	Pressure 50kg)		rance between the brake pedal and floor.
	The lining contact is defective.		Adjust with being installed not being dis-
			assembled. (Temperature should be 100
			°
			C or less)
	The surface of the lining is contaminated by th-		If it is contaminated by oil or grease, the-
	e oil, grease or water.		n replace it. If it is contaminated by water
	The lining is deteriorated.		, dry it.
	The vacuum force is too low.		Replace the lining.
	The drum surface is rough.		Check the pipe or the vacuum pump. If
			needed, replace.
	The brake booster is defective.		Adjust or Replace
	The brake oil level is too low.		Adjust or Replace
The clearance b-	The air intrudes.		Refill
etween the ped-
	Vapor lock		Air Exhausting
al and the floor i-
	The adjustment on pedal is defective.		Referring to the brake drawn item, adjust
s too narrow.
	The clearance is too large.		or replace. And then exhaust the air.
	The shoe clearance is too large.		Adjust the pedal clearance. Check the t-
			otal stroke.
	The cup of the master cylinder is defective.		Adjust the shoe clearance.
			If the wear exceeds the limit, replace.
	The brake shoe is deformed or damaged.		If the tightening does not satisfy the spe-
			cifications, replace the kit.
	The brake booster is defective.		Replace
	When the wheel is rotating with being lifted by		Replace
	jack, there are some noises.
During braking,	During braking (at low	Foreign materials in d-	Check that the brake is damaged. Remo-
the noise and s-	speed), noise is made	rum	ve the foreign materials.
hock are made	continually.
		Return spring is dama-	Check that the parts are damaged by br-
abnormally.
		ged.	oken parts. If needed, replace.
		Hold down cup is dam-	Check that the parts are damaged by br-
		aged.	oken parts. If needed, replace.
	The grease is deficien-	Improper adjustment	Check the rotating surface. Adjust
	cy in sliding parts.	on wheel bearing
		The lining is worn.	Replace
	The drum inside surface is rough.		Apply the grease.
			Modify the inner surface with sand paper
	The drum is cracked.		.
			Replace

Symptom	Causes			Remedy		Remark
The drum is ove-	The outlet of the brake master cylinder is clog-			If the booster operating rod is not proper-
rheated.	ged.			ly adjusted, adjust the pedal clearance of
				~
				the rod clevis to 10 15mm.
	The brake does not return.			Check the burst of the return spring, the
				bearing lubricant, the stop lamp switch a-
				djustment. If needed, adjust.
	The booster is defective.			Replace
	The vertical surface of the back plate is scratc-			If the surface is too rough, replace.
	hed.			If it is too dry, apply the grease.
	The wheel cylinder piston cup is defective.			Replace
	The oil return has problems due to the over tig-			Check the connector hole diameter. If it
	ht of the brake pipe nut.			is reduced, replace.
	When the wheel is rot-	The wheel bearing cle-		Replace bearing or adjust.		Specific
	ating with being lifted		arance is too large.			wheel is o-
	by jack, the wheel is h-					verheated.
			Shoe clearance is imp-	Adjust
	ard to rotate.		roper.
			Return spring is defec-	Check the part damages due to the spri-
			tive.	ng over working. If needed replace.
			Brake shoe is worn.	Replace
The pedal retur-	The pedal linkage is rusted or deformed.			Disassemble. Adjust or replace. Oil the
ning is defective.				grease.
	It is bursting due to the defectives on the pedal			Replace
	return spring.
				Adjust the pedal clearance with 10	~
	The booster operating rod is pushed.				15
				mm.
Brake is vibratin-	The drum is eccentrically centered.			Replace
g.
	The drum is deformed.			Replace
	The king pin bushing is worn.			Replace the bushing
	The hub bearing is worn.			Adjust (Check the rolling surface) or repl-
				ace.
Brake is drawn.	The pedal clearance is too narrow.			Adjust the booster working rod.
	The shoe clearance is improper.			Adjust
	The back plate vertical surface is rough.			Replace the back plate.
	The shoe spring is burst.			Replace
	The master cylinder or wheel cylinder piston c-			Replace
	up is deteriorated and swelled.

Symptom	Causes	Remedy	Remark
Brake makes n-	Brake shoe contacting is defective.	Adjust the lining with being installed not
oises.		being disassembled (Temperature shoul-
		°
		d be 100 C or less)
	Lining is deformed.	Replace the lining. Replace the drum if it
		has hardened surface.
	Drum has hardened surface.	Replace.
	Shoe is deformed.	Replace.
	Back plate is deformed or installed improperly.	Replace or adjust
	Front bearing is loosened.	Adjust (Check the rolling surface)
	Powder from the wear of the lining is adhered.	Clear
	Lining is worn.	Replace.
Exhaust brake	Vacuum pressure is improper.	Check the vacuum pump or piping. If ne-
does not work.		eded repair.
	Electric circuit is defective.	Check the clutch switch, the micro switch
		and the exhaust brake circuit. If needed,
		repair.
	Vacuum pipe is damaged.	Replace.
	3-way magnetic valve does not work.	Replace.
	Exhaust brake valve does not work.	Replace.
	Exhaust brake valve shaft is adhered.	Replace.
	Power chamber is defective.	Disassemble and check.
Exhaust brake c-	3-way magnetic valve does not work.	Replace.
an not be relea-
	Exhaust brake valve does not work.	Replace.
sed.
	Exhaust brake valve shaft is adhered.	Replace.
	Electric circuit is defective.	Check the clutch switch, the micro switch
		and the exhaust brake circuit. If needed,
		repair.

Diagnosis (Parking brake)

Symptom		Causes	Remedy	Remark
Parking brake d-	Operating	When pulling the parking brake wi-	Adjust the shoe clearance and cable.
oes not work.	mechanis-	th 30kg, there is no lever stroke cl-
	m has a p-	earance and shoe clearance.
	roblem.
		The locking status between the le-	Adjust the Ratchet pull lock status. Repl-
		ver lock latch and Ratchet pull is i-	ace it
		mproper.
		Wire is broken or elongated.	Replace the cable.
	Parking b-	Tolerance between the shoe clear-	Adjust the shoe clearance.
	rake is de-	ance and the brake lever pulling is
	fective.	too large.
		Drum inner surface is deformed or	Repair the drum inner surface. Replace
		twisted.	the lining.
		Lining is irregularly worn. Drum in-	Replace the lining.
		ner surface is contacted irregularly
		.
		The oil of drum and lining is conta-	Clear the inner surface of the drum. Rep-
		minated.	lace the lining.
Parking brake c-	Operating	Return spring is damaged. The te-	Replace the return spring.
an not be relea-	mechanis-	nsion of the return spring is inferior
sed.	m has a p-	.
	roblem.
		The inner cable does not move s-	Replace the cable.
		moothly.
		After the parking brake is released	Adjust the pulling tolerance limit.
		, the brake is operating.
	Parking b-	Return spring is damaged. The te-	Replace the return spring.
	rake is de-	nsion of the return spring is inferior
	fective.	.
		The shoe clearance is too narrow.	Adjust the shoe clearance.

On-Vehicle Inspection and Adjustment

Air bleeding of the Brake

1.Fill up the brake oil tank with the brake oil at the maximum level. During the air bleeding, if the level is lowered, refill the brake oil.

CAUTION

Be careful that the brake oil does not drop on the painted surface. If the brake oil contacts the painted surface, immediately wash it by water.

2.Connecting an end of transparent vinyl tubes at the air breather of the front wheel cylinder and the rear wheel cylinder, put the other end of the tubes into the transparent container having the brake oil.

KMTBR5518A

3.Step on the brake pedal several times. Pressing the brake pedal at half, loosen the air bleeder screw to evacuate the air with the brake oil.

And then, pressing the pedal until it reaches to the floor, tighten the air bleeder screw. Release the pedal. There procedures should be repeated until any air bubble is not shown in the brake oil.

KMTBR5519A

4. Tighten the bleeder screw

Tightening Torque for the bleeder Screw Front: 6.9~8.8Nm(0.7~0.9kgf.m, 5.1~6.5lb-ft) Rear : 6.9~8.8Nm(0.7~0.9kgf.m, 5.1~6.5lb-ft)

5.Step on the brake pedal several times. Pressing the brake pedal at half, loosen the air breather screw to evacuate the air with the brake oil.

And then, pressing the pedal until it reaches to the floor, tighten the air breather screw. Release the pedal. There procedures should be repeated until any air bubble is not shown in the brake oil.

KMTBR5520A

Adjustment of Brake Shoe Gap

1.Using the screw driver(A), turn the wheel cylinder adjuster(B) to the shoe expansion direction until the drum is not rotate anymore. Turn the adjuster reversely with the following notch number. (At that time, the drag torque between the lining and the drum should be less than 50kgf.m).

	KMTBR5521A
The Notch Number for reverse rotation of the
Adjuster.
Front Wheel Cylinder	Auto adjuster type	~
		9	11
	Manual adjuster type	~
		4	6
Rear Wheel Cylinder	Auto adjuster type	~
		9	11
	Manual adjuster type	~
		4	6

Specifications

Front Wheel Brake (Drum Type)

Item		Specifications
Brake type		2-leading Brake
Wheel cylinder	Inner diameter	31.75mm
Brake drum	Inner diameter	320mm
Brake lining	Width x Thickness (mm)	85 x 10(Standard), 110 x 11(Option in case of HD72,78)

Front wheel Brake (Disk Type)

Item	Specifications
Cylinder diameter	Ø 76 mm
Effective radius	118 mm
Disk outer diameter	Ø 304 mm
Disk inner diameter	Ø 164 mm
Pad thickness	12.5 mm
Pad effective thickness	10.5 mm

Rear Wheel Brake

Item		Specifications
Brake type		2-leading Brake
Wheel cylinder	Inner diameter	28.57mm
Brake drum	Inner diameter	320mm
Brake lining	Width x Thickness (mm)	85 x 10(Standard), 110 x 11(Option in case of HD72,78)

Brake system

Item			Specification
Brake Pedal	Total Stroke		140 mm
Booster	Total Stroke		31 mm
Master Cylinder	Inner Diameter		Ø 31.75 mm, Ø 30.15 mm
	Stroke	Piston	±
			31 1 mm
		Primary	17 ± 0.5 mm
		Secondary	14 ± 0.5 mm

Exhaust Brake

Item			Specification
Control System			Combination of Electric and Vacuum Type
Exhaust Brake Valve Type			Butterfly Valve
Exhaust Brake Cham-	Diaphragm Effective Diameter		76.2mm
ber
	With Installing	Spring Tension	~	~
			90 110 (9.18	11.22)
	N(kg)
		Rod Tensile Force	142.1(14.5): Vacuum Pressure-400mmHg
		Spring Tension	~	~
			125 153 (12.78 15.62)
		Rod Tensile Force	103(10.5) Vacuum Pressure-400mmHg

Parking brake

Item		Specification
Type		Internal expansion type acting on propeller shaft
Control		Mechanical cable
Parking lever	Normal stroke	~
		8 9 clicks(20 kgf)
Parking brake size	Drum i.d. x Lining width x Li-	180 x 35 x 5	(T/M : M2S5, M3S5)
	ning thickness	190 x 45 x 4	(T/M : M035S5)
		230 x 55 x 4	(T/M : T60S5, T60S6)

SERVICE STANDARDS

			Description		Nominal value, mm		Limit	Correction and
					(Basic diameter in [ ])		(mm)	remarks
Brake	Bushing to collar clearance				[16]0.02 to 0.26		0.5	Replace bushing
pedal
	Brake pedal play				3-8			Adjust
	Stop lamp switch installation clearance				0 to 1			Replace
Brake	Primary and secondary piston to cylinder body clearance				0.038 ~ 0.145		0.2	Replace
master
cylinder
	Primary retainer assembly			Free length	38.1			Replace
	Secondary spring deterioratio-			Free length	37.7			Replace
	n
Front	Brake drum		I.D.		320		322	Replace
drum b-
	Brake lining		Thickness		10		4	Replace
rake
	Return spring				±		19/227	Replace
					30 3/227
	Wheel cylinder body to piston clearance				[31.75]0.03 to 0.13		0.2	Replace
	Brake shoe clearance(No. of notches returned of wheel c-				Auto	~		Adjust
						9 11
	ylinder adjuster)
					Manual	~
						4 6
Rear w-	Brake drum		I.D.		320		322	Replace
heel br-
	Brake lining		Thickness		10		4	Replace
ake
	Return spring		Load N(kgf)/installed length		±		19/227	Replace
					30 3/227
	Wheel cylinder		Body to piston clearance		0.02-0.11		0.2	Replace
	Brake drum		Out of roundness		0.05		-	Replace
	Brake shoe clearance (number of return notches of wheel				Auto	~		Adjust
						9 11
	cylinder adjuster)
					Manual	~
						4 6

		Description			Nominal value, mm	Limit	Correction and
					(Basic diameter in [ ])	(mm)	remarks
Exhau-	Power chamber air tightness [15 seconds after applicatio-				-63 kPa (-475 mmHg) or		Replace
st brak-	n of -67 kPa (-500 mmHg) negative pressure]				more
e
	Valve to body clearance when butterfly valve is fully clos-				0.1 to 0.4mm		Replace
	ed [at power chamber vacuum -87 to -93 kPa(-650 to -70
	0 mmHg)
	3-way magnet	Air tightness	When -100 kPa (-750 m-		No air to be sucked in f-		Replace
	valve		mHg) negative pressure is		rom atmosphere side
			applied from vacuum tan-
			k side to operate valve wi-
			th exhaust brake unit side
			plugged tightly
			When 98 kPa (1 kgf/cm²		No air to leak from vacu-		Replace
			air pressure is applied fro-		um tank side
			m atmosphere side to op-
			erate valve with exhaust
			brake unit side plugged ti-
			ghtly
		Minimum op-	When -100 kPa(-75	24V	22V or less		Replace
		erating volta-	0 mmHg) negative	type
		ge	pressure is applied	unit
			to vacuum tank side
			When 98 kPa (1 kgf	24V	22V or less		Replace
			/cm² air pressure is	type
			applied from atmos-	unit
			phere side with exh-
			aust brake unit side
			plugged tightly

SERVICE STANDARDS (Parking brake)

Description			Nominal value, mm	Limit	Correction		and
			(Basic diameter in [ ])	(mm)	remarks
Brake drum	I.D.		180	181	Correct	to	limit,
					replace	when li-
			190	192
					mit is reached.
			230	232
	Squareness		0.05 or less		Correct or repla-
					ce
	Concentricity		0.1 or less
	Cylindricity		0.1 or less
	Static rotation imbalance		0.49 N.cm(50 gf.cm) or l-
			ess
Brake lining thickness		Model with M2S5 T/M	10 ~ 11	4.0	Replace
Brake shoe clearance		Model with M2S5 T/M	0.25 to 0.35		Adjust
Brake shoe r-	Free length	Model with M2S5 T/M	98	-
eturn spring
	Load N (kgf)/instal-	Model with M2S5 T/M	67 to 86 (6.8 to 8.8)/104	104.364	Replace
	led length			(6.5)/104
Shoe hold d-	Spring A(longer o-	Free length	34.1		Replace
own spring	ne of free length)
		Load N (kgf)/installed l-	59 to 69 (6.0 to 7.0)/13.7	59 (6.0)/13.7
		ength
	Spring B(shorter o-	Free length	23.6
	ne of free length)
		Load N (kgf)/installed l-	59 to 69 (6.0 to 7.0)/10.5	59 (6.0)/10.5
		ength

Tightening torque table

Description	Tightening torque
	Nm			Kgf.m		Lb-ft
Mounting nut between the master cylinder and booster		~		~		~
	17.7 24.5			1.8	2.5	13	18.1
Master cylinder set bolt	~			~		8.7	~
	12	16		1.2	1.6		11.6
Brake booster mounting nut		~		~		9.4	~
	12.7 15.7			1.3	1.6		11.8
Brake booster clevis lock nut		~		~			~
	15.7 21.6			1.6	2.2	11.6 15.9
Master cylinder outlet port nut		~		~		9.4	~
	12.7 16.8			1.3	1.7		12.3
LSPV connecting link mounting bolt	~			~			~
	22	33		2.2	3.3	15.9 23.9
LSPV flange bolt mounting bolt	~			~			~
	22	33		2.2	3.3	15.9 23.9
Front drum brake air bleeding port	6.9	~		~		5.1	~
		12.7		0.7	1.3		9.4
Front spindle mounting bolt	~			~		~
	98	137		10	14	72	101
Brake hose to union mounting bolt(Front drum brake)		~		~			~
	24.5 29.4			2.5	3	18.1 21.7
Exhaust brake to exhaust pipe mounting bolt		~		~			~
	44.1 58.8			4.5	6	32.5 43.4

Vacuum Assisted Hydraulic Brake

Brake Pedal

Component

SUDBRA003L

1.	Clevis pin	5.	Booster
2.	Hose connector	6.	Pedal assembly
3.	Grommet	7.	Return spring
4.	Master cylinder

Removal

1.Loosen the steering column assembly mounting bolt. Pull down the steering column.

2.Loosen the bolt(A), Remove the instrument panel(B).

KMTBR5003A

3.Remove the master cylinder (Refer to the BR-"Master cylinder")

4.Remove the brake booster (Refer to the BR-"Booster")

5.Remove the brake light switch.

6.Remove the shaft bolt(A) connected to the bracket.

KMTBR5040A

Installation

1.Install the brake pedal assembly(A) to the bracket(B).

CAUTION

Before the assembling, apply the grease inside of the brake pedal assembly pipe.

KMTBR5527A

2.Install the brake light switch.

3.Install the booster and the master cylinder.

CAUTION

Apply the grease on the clevis pin and the washer

Adjustment

Adjust the height of the brake pedal

1.Turn the booster operating rod so that the distance from the center of the brake pedal pad to the A point of the instrument panel lower portion is the 'B'. After adjusting, fix the clevis with the nut. Check that the maximum stroke of the pedal is more than 'C' (before filling the brake oil)

SUDBRA004L

	Engine	B(mm)		C(mm)
Non A-	D4DD, D4GA	±		±
		280	2	140	4
BS
	The others	±		±
		273	3	140	4
ABS	D4DD, D4GA	±		±
		280	2	140	4
	The others	±		±
		273	2	140	4

Free play clearance of the Brake pedal

1.Setting the brake pedal to the original position, check if the free play(B) clearance is 5mm at least by pressing the pedal(A).

If the clearance excesses the reference, re-adjust the position of the brake pedal.

CAUTION

When checking the free play clearance of the brake pedal, the master back negative pressure should be 0.

KMTBR5005A

Gap between the brake pedal and the floor.

1.After cranking the engine, check if the gap between the floor and the pedal is more than 45mm by pressing the pedal with 50kg.

EMTBR5023A

Stop Lamp Switch

1.Adjusting the gap between the end of the brake. Stop lamp switch screw and the pedal stopper to 0~1mm, tighten the locknut.

SUDBR9014L

Brake Booster

Components

SUDBRA005L

1.	Clevis pin	5.	Booster
2.	Hose connector	6.	Pedal assembly
3.	Grommet	7.	Return spring
4.	Master cylinder