1991 MAZDA MIATA BEARING CLEARANCE

S120-645A) and Wrench (49-0603-635A).
2. Using Puller (49-S120-520A) and Adapter (49-S120-523A), remove rear axle bearings. Remove oil seal
from axle housing.
Installation
1. Install oil seal in axle housing. Install bearing inner race. Install and position oil seal flush with end of
axle casing. Apply multipurpose grease to oil seal lip. Install spacer with concave side facing backing
plate.
2. Press axle bearing onto axle shaft. Using wrench, install and tighten lock nut to 145-217 ft. lbs. (197-295
N.m). Install axle shaft assembly. Install backing plate. Reconnect brake line and parking brake cable.
Install brake drum and wheel. Bleed brake system.
MASTER CYLINDER
Removal
1. Disconnect fluid level sensor coupler (if equipped). Disconnect and plug hydraulic lines at master
cylinder to prevent entry of dirt and loss of fluid.
2. Remove nuts attaching master cylinder to firewall or power brake unit. Remove master cylinder from
vehicle. On RX7, remove proportioning valve by-pass bolt.
Installation
1. Place Adjustment Gauge (49-F043-001) onto master cylinder. Turn screw on adjuster gauge until it
contacts piston. Remove adjuster gauge. Apply 19.7 in. Hg to power brake unit.
2. Invert adjuster gauge and place it on power brake unit. Adjust push rod on power brake unit until there is
no clearance between push rod and adjuster gauge screw. Install master cylinder. Bleed hydraulic system.
POWER BRAKE UNIT
Removal & Installation
1. Remove master cylinder from power brake unit. See MASTER CYLINDER under REMOVAL &
INSTALLATION . Disconnect vacuum line at power brake unit. From inside vehicle, remove cotter pin
and clevis pin. Separate push rod from brake pedal.
2. Remove power brake unit-to-firewall nuts. Remove power brake unit. See Fig. 22
To install, reverse
removal procedure. Bleed hydraulic system. NOTE: Left wheel lock nut has left-hand threads.

1991 Mazda MX-5 Miata
BRAKE SYSTEM 1991 BRAKES Mazda Brake System
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3. Using Bearing Nut Wrench (49 0603 635A ) and Shaft Holder (49 S120 645A ), remove bearing lock nut
from axle shaft. Remove bearing and bearing retainer from axle using Puller (49 S120 520A ). Remove
outer race from hub.
END PLAY SPECIFICATIONS
(1)
Installation
1. Press new oil seal and bearing outer race into bearing retainer. Coat bearing race and outer seal with
grease. Tap inner oil seal flush with end of axle housing. Coat inner seal lip with grease.
2. Position brake backing plate onto axle shaft. Install spacer against backing plate with chamfer facing
backing plate. Using Press Attachment (49 S120 748 ) and a press, install wheel bearing onto axle shaft.
Standard press force is 4.6-6.7 tons (4200-6100 kg). If press fit force is too high or too low, replace the
bearing collar or shaft.
3. Using Bearing Nut Wrench (49 0603 635A ), install bearing lock nut to axle shaft and tighten to 145-217
ft. lbs. (196-245 N.m). Bend tab up into groove. Install one axle shaft into axle housing. Tighten backing
plate nuts to specification. Install dial indicator on backing plate and check drive axle end play.
4. To adjust end play, remove axle and insert appropriate size adjustment shim between axle hub and
housing. End play for second drive axle installed should be set to normal end play clearance of .002-
.010" (.05-.25 mm), with both axles installed.
5. Install parking brake cable, attaching pin and brake line. Install brake shoes and actuating hardware.
Bleed brake system. Install wheel and tire.
BEARING RETAINER SHIMS (B2200 & B2600i)
MPV 4WD
NOTE: On B2200 and B2600i, left axle bearing lock nut has left-hand threads.
ApplicationIn. (mm)
B2200 & B2600i
One Axle Installed.026-.037 (.65-.95)
Both Axles Installed.002-.010 (.05-.25)
(1)Check at axle flange with dial indicator.
NOTE: Ensure end play for first drive axle is within specification before inserting
second drive axle. Use shims to adjust end play if necessary.
Part NumberThickness In. (mm)
083 26 165.004 (.10)
083 26 166.006 (.15)
083 26 167.020 (.50)
083 26 168.030 (.75)

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
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4. Subtract thickness from 3.701" (94.00 mm). Difference should be .004-.016" (.10-.40 mm). If clearance is
not as specified, install oversize thrust washers. See RX7 DIFFERENTIAL SPECIFICATIONS
.
5. Install parts in proper order. See Fig. 8
. Before installing thrust washers, coat with grease. When
installing conical springs, ensure concave side faces side gears. Align differential case and cover
alignment marks. Apply locking compound to rear face of ring gear. Install ring gear and tighten ring gear
retaining bolts to 51-61 ft. lbs. (69-83 N.m).
RX7 DIFFERENTIAL SPECIFICATIONS (LIMITED SLIP)
Pinion Assembly (B2200, B2600i, Miata, Protege 4WD & 929)
1. Using a press, install pinion bearing races in differential housing. Place original spacer, rear bearing and
Bearing Collar (49 H027 001 ) onto Drive Pinion (49 8531 565 ). Secure collar with "O" ring. Install
assembly into differential housing.
2. Install front bearing, Collar (49 8531 567 on 929 or 49 U027 001 on B2200 and B2600i), companion
flange, washer and original drive pinion nut. See Fig. 11
. Tighten flange nut so assembly can be turned
by hand.
3. Place a dial indicator on Pinion Height Gauge (49 0727 570 ). Place pinion height gauge on a flat surface
and zero dial indicator. Position Gauge Block on top of Drive Pinion (49 F027 001 ). See GAUGE
BLOCK SELECTION .
GAUGE BLOCK SELECTION
ApplicationIn. (mm)
Friction Disc Thickness
Standard.079 (2.0)
Limit.075 (1.9)
Friction Plate
Standard.079 (2.0)
Limit.075 (1.9)
Oversize.083 (2.1)
Thrust Washer
Standard.063 (1.6)
Limit.055 (1.4)
Oversize.071 (1.8)
ApplicationUse Gauge Block No.
Front Differential
B2600i
& MPV
4WD49 0305 555
Rear Differential
B220049 0305 555
B2600i,
Protege 49 0660 555

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
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