LEXUS SC300 1991 Service Repair Manual

(c) Repeat (b) until the disc has been installed on the 3remaining hub positions.
(d) If the minimum runout recorded in (b) and (c) is less than 0.05
mm (0.0020 in.), install the disc in that position.
(e) If the minimum runout recorded in (b) and (c) is greater than 0.05 mm (0.0020 in.), replace the disc and repeat step 3.
(f) Install the torque plate and tighten the 2 bolts.
Torque: 104 N Vm (1,065 kgf Vcm, 77 ft Vlbf)
CALIPER ASSEMBLY
BR0EQ±04
1. APPLY LITHIUM SOAP BASE GLYCOL GREASE TO
PARTS INDICATED WITH ARROWS
2. INSTALL DUST BOOTS AND SLIDING PINS
(a) Using a 19 mm socket and hammer, tap in 2 new dust boots into the torque plate.
(b) Confirm that the metal plate portion of the dust boot fits snugly in the torque plate.
(c) Insert 2 sliding pins into the torque plate.
NOTICE: Insert the sliding pin with the sliding bushing into the
bottom side.
BR±42±
BRAKE SYSTEM REAR BRAKE (Disc Brake)
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3. INSTALL PISTON SEAL AND PISTON IN CALIPER
4. INSTALL CYLINDER BOOT AND CYLINDER BOOT SETRING
CALIPER INSTALLATION
BR0ER±04
1. INSTALL FOLLOWING PARTS:
(a) 2 brake pads
(b) 2 anti±squeal springs
2. INSTALL CALIPER
(a) Temporarily install the caliper on the torque plate with 2installation bolts.
(b) Hold the sliding pin and torque the installation bolts.
Torque: 34 N Vm (350 kgf Vcm, 25 ft Vlbf)
3. CONNECT FLEXIBLE HOSE
Install the flexible hose on the caliper with 2 new gaskets.
Torque: 30 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Install the flexible hose lock securely in the lock hole
in the caliper.
4. FILL BRAKE R ESERVOIR WITH BRAKE FLUID AND
BLEED BRAKE SYSTEM
(See page BR±8)
5. CHECK FOR LEAKS
±
BRAKE SYSTEM REAR BRAKE (Disc Brake)BR±43
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REAR BRAKE
(Parking Brake)
COMPONENTS
BR04E±06
PARKING BRAKE DISASSEMBLY
BR04F±09
1. REMOVE REAR WHEEL
2. REMOVE REAR DISC BRAKE ASSEMBLY
(a) Remove the 2 mounting bolts and remove the disc brakeassembly.
(b) Suspend the disc brake so the hose is not stretched.
3. REMOVE DISC
(a) Place matchmarks on the disc and rear axle hub.
(b) Remove the disc. HINT: If the disc can not be removed easily, return the shoe
adjuster until the wheel turns freely.
BR±44
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)
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4. REMOVE SHOE RETURN SPRINGSUsing needle±nose pliers, remove the 2 shoe return springs.
5. REMOVE SHOE STRUT WITH SPRING
6. REMOVE FRONT SHOE ADJUSTER AND TENSION SPRING
(a) Slide out the front shoe and remove the shoe adjuster.
(b) Disconnect the tension spring and remove the front shoe.
7. REMOVE REAR SHOE
(a) Slide out the rear shoe.
(b) Remove the tension spring from the rear shoe.
(c) Disconnect the parking brake cable from the parking brake
shoe lever.
(d) Remove the shoe hold±down spring cups, springs and pins.
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)BR±45
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PARKING BRAKE COMPONENTS
INSPECTION AND REPAIR
BR04G±0B
1. INSPECT DISASSEMBLED PARTSInspect the disassembled parts for wear, rust or damage.
2. MEASURE BRAKE SHOE LINING THICKNESS Using a scale, measure the thickness of the shoe lining.
Standard thickness:
2.5 mm (0.098 in.)
Minimum thickness: 1.0 mm (0.039 in.)
If the lining thickness is at the minimum thickness or less, or
if there is extremely uneven wear, replace the brake shoe.
3. MEASURE BRAKE DISC INSIDE DIAMETER Using a vernier caliper, measure the inside diameter of the
disc.
Standard inside diameter:
190 mm (7.48 in.)
Maximum inside diameter: 191 mm (7.52 in.)
Replace the disc if the inside di ameter is at the maximum val-
ue or more. Replace the disc or grind it with a lathe if the disc
is scored or is worn unevenly.
4. INSPECT P ARKING BRAKE LINING AND DISC FOR
PROPER CONTACT
Apply chalk to the inside surface of the disc, then grind down
the brake shoe lining to fit. If the contact between the disc and
the brake shoe lining is improper, repair it using a brake shoe
grinder or replace the brake shoe assembly.
5. MEASURE CLEARANCE BETWEEN PARKING BRAKE SHOE AND LEVER
Using a feeler gauge, measure the clearance.
Standard clearance:
Less than 0.35 mm (0.0138 in.)
If the clearance is not within the specification, replace the
shim with one of the correct size.
BR±46
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)
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Thickness mm(in.) Thickness mm(in.)
 0.3 (0.012) 0.9 (0.035)
 

0.6 

(0.024) 


 


6. IF NECESSARY, REPLACE SHIM
(a) Remove the parking brake shoe lever, and install the correct
size shim.
(b) Install the parking brake shoe lever with a new Cwasher.
(c) Remeasure the clearance.
PARKING BRAKE ASSEMBLY
BR0ES±04
HINT: Assemble the parts in the correct direction, as shown.
1. APPLY HIGH TEMPERATURE GREASE ON BACK± ING PLATE
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)BR±47
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2. APPLY HIGH TEMPERATURE GREASE TO ADJUSTER
3. CONNECT PARKING BRAKE CABLE TO PARKINGBRAKE LEVER
(a) Install the shoe hold±down springs, cups and pins.
(b) Connect the parking brake cable to the parking brake shoe
lever of the rear shoe.
4. INSTALL REAR SHOE Slide in the rear shoe between the shoe hold±down spring
cup and the backing plate.
NOTICE: Do not allow oil or grease to get on the rubbing face.
5. INSTALL TENSION SPRING, FRONT SHOE ANDADJUSTER
(a) Install the tension spring on the rear shoe.
(b) Install the front shoe on the tension spring.
(c) Install the adjuster between the front and rear shoes.
(d) Slide in the front shoe between the shoe hold±down spring
cup and the backing plate.
BR±48
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)
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6. INSTALL SHOE STRUT WITH SPRINGInstall the strut with the spring forward.
7. INSTALL SHOE RETURN SPRINGS Using needle±nose pliers, install the front shoe return spring
and then install the rear shoe return spring.
8. INSTALL DISC
(a) Before installing, polish the disc and shoe surfaces with sandpaper.
(b) Align the matchmarks and install the disc. HINT: If there are no matchmarks, temporarily install the disc,
then measure the disc runout and install the disc in the posi-
tion.
(See page BR±41)
9. ADJUST PARKING BRAKE SHOE CLEARANCE
(a) Temporarily install the hub nuts.
(b) Remove the hole plug.
(c) Turn the adjuster and expand the shoes until the disc locks.
(d) Return the adjuster 8 notches.
(e) Install the hole plug.
10. INSTALL REAR DISC BRAKE ASSEMBLY Install the disc brake assembly and torque the 2 mounting
bolts.
Torque: 104 N Vm (1,065 kgf Vcm, 77 ft Vlbf)
11. INSTALL REAR WHEEL
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)BR±49
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12. SETTLING PARKING BRAKE SHOES AND DISC
(a) Drive the vehicle at about 50 km/h (31 mph) on a safe, leveland dry road.
(b) With the parking brake release button pushed in, pull on the
lever with 88 N (9 kgf, 19.8 lbf) of force.
(c) Drive the vehicle for about 400 meters (0.25 mile) in this condition.
(d) Repeat this procedure 2 or 3 times.
13. CHECK AND ADJUST PARKING BRAKE LEVER TRAVEL
BR±50
±
BRAKE SYSTEM REAR BRAKE (Parking Brake)
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PROPORTIONING AND BY±PASS
VALVE (P & B VALVE)
FLUID PRESSURE INSPECTION
BR0ET±01
1. INSTALL LSPV GAUGE (SST) AND BLEED AIRSST 09709±29017
2. RAISE MASTER CYLINDER PRESSURE AND CHECKREAR WHEEL CYLINDER PRESSURE
 Master cylinder pressure Rear wheel cylinder pressure
 1,961 kPa 1,961 kPa 

(20 kgf/cm2, 284 psi) 

(20 kgf/cm2, 284 psi)
 7,845 kPa5,492 kPa
 (80 kgf/cm2, 1,138 psi) (56 kgf/cm2, 796 psi)
Specifications: If the rear wheel cylinder pressure is in-
correct, replace the master cylinder.
3. BLEED BRAKE SYSTEM
4. CHECK FOR FLUID LEAKAGE
±
BRAKE SYSTEM PROPORTIONING AND BY±PASS VALVE (P & B
VALVE)BR±51
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