Disc & Drum - Except Evolution: Other Mitsubishi Lancer IX

BLEEDING BRAKE SYSTEM

MASTER CYLINDER BLEEDING

The master cylinder has no check valve, so if bleeding is carried out by the following procedure, bleeding of air from the brake line will become easier.

1. Fill the reserve tank with brake fluid.
2. Keep the brake pedal depressed.
3. Have another person cover the master cylinder outlet with a finger.
4. With the outlet still closed, release the brake pedal.
5. Repeat steps 2 - 4 three or four times to fill the inside of the master cylinder with brake fluid.

BRAKE LINE BLEEDING

Start engine, and bleed system in sequence shown in illustration. (Scheme 7)

Scheme 7

Scheme 8

Scheme 9

Scheme 10

1. Turn up the carpet etc. under the brake pedal. Measure the brake pedal height as illustrated. (Scheme 8)
2. If distance between surface of floorboard to face of pedal pad is not 6.7-6.8" (169.1-172.1 mm), adjust as follows: Disconnect the stoplight switch connector. Remove brake booster. See «POWER BRAKE BOOSTER»(ref-162808-S39146426912004061100000) under REMOVAL & INSTALLATION. Adjust brake pedal height by turning the clevis. (Scheme 9) NOTE: When the clevis is turned 180 degrees, the pedal height is changed by approximately.09" (2.4 mm). Install brake booster. Measure brake pedal height again. If brake pedal height is not within specification, go to step b. Screw in the stop light switch until its thread contacts the stopper. Turn the stoplight switch 1/4 turn clockwise to secure. Turn the stoplight switch 1/4 turn clockwise to secure. Confirm that the clearance between the switch plunger and the stopper is as shown in illustration. (Scheme 10) Connect the connector of the stoplight switch. Check to be sure that the stoplight does not illuminated with the brake pedal released.
3. Return the carpet, etc. to its original position.
4. On vehicles with A/T, check shift lock mechanism. See appropriate article in TRANSMISSIONS.

BRAKE PEDAL FREE PLAY

1. Turn ignition switch to "LOCK" (OFF) position. Depress brake pedal 2 or 3 times. After eliminating vacuum in brake booster, press pedal down by hand, and confirm that the amount of movement before resistance is met (free play) is .12-.31" (3-8 mm).
2. If brake pedal free play is not within the standard value, check the following, and adjust or replace if necessary: Excessive play between the brake pedal and the clevis pin, or between the clevis pin and the brake booster operating rod. Brake pedal height. Installation position of the stoplight switch, etc.

Scheme 11

1. Turn up the carpet etc. under the brake pedal.
2. Start the engine, depress the brake pedal with approximately 110 lbs. (490 N) of force, and measure the clearance between the brake pedal and the floorboard. (Scheme 11)
3. If clearance is not 3.5" (90 mm) or more, check for air trapped in the brake line, thickness of the disc brake pad, clearance between brake lining and brake drum, and dragging in the parking brake. Adjust or replace defective parts as required.
4. Return the carpet etc. to its original position.

Scheme 12

Scheme 13

1. Measure protruding length "A" at the pushrod. (Scheme 12) Push rod protruding length should be.361-.371" (9.18-9.43 mm). NOTE: When a negative pressure of 19.6 in. Hg is applied to the brake booster, push rod protruding length should be.405-.415" (10.28-10.53 mm).
2. If the protruding length is not as specified, change pushrod length by turning the end of the pushrod using Push Rod Adjusting Socket (MB991568) while holding rod spline with angle-nose pliers. (Scheme 13)

Scheme 14

1. Pull the parking brake lever with a force of approximately 45 lbs. (200 N) and count the number of notches.
2. Parking brake lever stroke should be 5-7 notches. If parking brake lever stroke is not as specified, adjust as described below. Remove floor console assembly. Loosen the adjusting nut to move it to the cable rod end so that the cable will be free. (Scheme 14) Depress brake pedal repeatedly until lever has no change in its stroke. Turn adjusting nut to adjust parking brake lever stroke. After adjusting, ensure that there is no space between adjusting nut and parking brake lever. Ensure adjusting nut is secured with nut holder. CAUTION: If parking brake lever stroke is less than specification and brake pedal is too firm, rear brakes may drag. After adjusting parking brake lever stroke, raise rear of vehicle, release parking brake and turn rear wheels to ensure rear brakes are not dragging.

PARKING BRAKE SWITCH

Remove floor console. Remove right front seat. Check continuity between parking brake switch terminal and switch mounting bolt. (Scheme 15) When parking brake lever is pulled, resistance should be less than 2 ohms. When parking brake lever is released, circuit should be open.

Scheme 15

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. Check brake booster check valve operation. Repair or replace as necessary.

PROPORTIONING VALVE (VEHICLES WITHOUT ABS)

Scheme 16

1. Connect two pressure gauges to the output port of the master cylinder and output port of the proportioning valve. (Scheme 16)
2. Bleed brake system and gauges. See «BLEEDING BRAKE SYSTEM»(ref-162808-S00730203632004061100000).
3. Depress the brake pedal gradually. Then check that the split point, where the output fluid pressure begins to drop in proportion to the output fluid pressure, is 390-463 psi (2690-3190 kPa).
4. Depress the brake pedal more strongly than at the above step. Then check that the output fluid pressure is 532-605 psi (3670-4170 kPa) when input fluid pressure is 995 psi (6860 kPa).
5. Measure each output fluid pressure at both valves, and check that the difference between the two is 73 psi (500 kPa) or less. If the measured pressure exceeds the limit, replace the proportioning valve.

FRONT DISC BRAKE PADS

POWER BRAKE BOOSTER CHECK VALVE

Note. To test check valve before removal, see POWER BRAKE BOOSTER under TESTING.