Disc: Other Mazda MX-5 NB рестайлинг

BLEEDING BRAKE SYSTEM

Note. If vehicle is equipped with anti-lock brakes, see appropriate ANTI-LOCK article, for bleeding procedure.

Note. The brakes should be bled whenever a brake line is disconnected.

BRAKE LINE BLEEDING SEQUENCE

BLEEDING BRAKES

1. On level ground, jack up the vehicle and support it evenly on safety stands.
2. Remove the bleeder cap and attach a vinyl tube to the bleeder screw. (Scheme 25)
3. Place the other end of the vinyl tube in a clear container.
4. The first person depresses the brake pedal a few times, and then holds it in the depressed position.
5. The second person loosens the bleeder screw, drains out the fluid and closes the bleeder screw.
6. Repeat steps 4 and 5 until no air bubbles are seen. The reservoir should be kept about 3/4 full during bleeding to prevent air from reentering the lines.
7. Inspect for correct brake operation.
8. Verify that there is no fluid leakage. Wipe off any spilled fluid immediately.
9. After bleeding the brakes, add brake fluid to the maximum level.

Scheme 25

BRAKE PEDAL FREE PLAY

1. With engine off, depress pedal a few times to eliminate vacuum. Depress brake pedal by hand, and check pedal free play. See «BRAKE PEDAL FREE PLAY SPECIFICATIONS»(ref-139611-S33171960462002050200000) table. If free play is not as specified, go to next step.
2. Remove the spring pin and the clevis pin. (Scheme 26)
3. Loosen lock nut "D" and turn rod "C" to align the holes in the fork and in the pedal. (Scheme 27)
4. Install the clevis pin and the spring pin.
5. Verify the pedal height and the brakelight operation.

BRAKE PEDAL FREE PLAY SPECIFICATIONS

Scheme 26

BRAKE PEDAL HEIGHT & BRAKELIGHT SWITCH

1. Disconnect the brakelight switch connector.
2. Loosen lock nut "B" and turn switch "A" until it does not contact the pedal. (Scheme 27)
3. Loosen lock nut "D" and turn rod "C" to adjust the height.
4. Tighten the bolt with lock nut "B" so that clearance between the bolt for brakelight switch "A" and pedal stopper is within the specification. (Scheme 27) Tighten lock nut to specifications. See «TORQUE SPECIFICATIONS»(ref-139611-S12717708312002050200000).
5. Connect the brakelight switch connector.
6. After adjustment, inspect the pedal play and the brakelight operation.

Scheme 27

MASTER CYLINDER PUSH ROD

Note. Push rod has an adjustment screw to maintain correct distance between booster push rod and master cylinder piston. If push rod is adjusted too long, it prevents master cylinder piston from completely releasing hydraulic pressure, causing brakes to drag. If push rod is adjusted too short, it causes excessive pedal travel and an undesirable clunk in booster area. To determine which of the following adjustment procedures to use see MASTER CYLINDER INSTALLATION NOTE under MASTER CYLINDER under REMOVAL & INSTALLATION.

Note. The threads of the push rod are specially designed so that the bolt becomes harder to turn past a certain point. This is to prevent the bolt from coming loose. Turn the bolt only within this range when adjusting.

Adjusting The Push Rod Clearance At B

1. Push lightly on the end of the Adjustment Gauge (49-B043-001), and measure the clearance between the adjusting nut and the adjustment gauge body. (Scheme 28)
2. Turn the nut to lengthen the power booster push rod an amount equal to the sum subtracting 0.004-0.016" (0.1-0.4 mm} from the clearance measured at "B"in Step 1. (Scheme 29)

Note. The threads of the push rod are specially designed so that the bolt becomes harder to turn past a certain point. This is to prevent the bolt from coming loose. Turn the bolt only within this range when adjusting.

Adjusting The Push Rod Clearance At "C" Or No Clearance At "B" Or "C"

1. Measure and record height "D1" of the Adjustment Gauge (49-B043-001). (Scheme 30)
2. Turn the adjusting nut until the adjustment gauge body sets squarely on the master cylinder. Turn only enough for the body to touch.
3. Measure and record height "D2" of the adjustment gauge rod. (Scheme 31)
4. Subtract "D1" from "D2" and add 0.004-0.016" (0.1-0.4 mm). Turn the nut to shorten the power booster push rod an amount equal to the sum. (Scheme 29)

Scheme 28

Scheme 29

Scheme 30

Scheme 31

Checking For Vacuum Loss (Unloaded Condition)

1. Start the engine.
2. Stop the engine when the vacuum gauge indicates 19.7 in. Hg. (66.7 kPa).
3. Observe the vacuum gauge for 15 seconds. If the gauge indicates 18.8-19.6 in. Hg. (63.4-66.6 kPa), the unit is operating.

Checking For Vacuum Loss (Loaded Condition)

1. Start the engine.
2. Depress the brake pedal with a force of 44 foot pounds (196 N.m).
3. With the brake pedal held depressed, stop the engine when the vacuum gauge indicates 19.7 in. Hg. (66.7 kPa).
4. Observe the vacuum gauge for 15 seconds. If the gauge indicates 18.8-19.6 in. Hg. (63.4-66.6 kPa), the unit is operating.

Checking For Hydraulic Pressure

1. With the engine is stopped vacuum 0 in. Hg. (0 kPa), depress the break pedal with a force of 44 foot pounds (196 N.m), and the fluid pressure is 107 psi.
2. Start the engine. Depress the brake pedal when the vacuum reaches 19.7 in. Hg. (66.7 kPa), depress the break pedal with a force of 44 foot pounds (196 N.m). The unit is operating, if the fluid pressure is, with ABS: 1,038 psi, without ABS (vehicle equipped with 16" wheel) 683 psi or without ABS (vehicle equipped with 15" wheel): 1,038 psi.

PROPORTIONING VALVE

Connect 2 pressure gauges and adapters to brake pipes. (Scheme 32) Bleed brake system. See BLEEDING BRAKE SYSTEM. Measure fluid pressure from master cylinder and to rear brakes. If not as specified, replace proportioning valve. See PROPORTIONING VALVE PRESSURE SPECIFICATIONS table.

PROPORTIONING VALVE PRESSURE SPECIFICATIONS

Scheme 32

REAR AXLE BEARING & OIL SEAL

Note. For rear axle bearing and oil seal procedures, see appropriate REAR article in SUSPENSION.