1991 MAZDA MIATA Factory Service Manual

Fig. 7: Manual Heater-A/C System Wiring Diagram (1992)

1991 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems
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STEERING GEAR - POWER RACK & PINION
1991 STEERING Mazda - Power Rack & Pinion
DESCRIPTION
Steering system is a power-assisted rack and pinion. The system consists of a rack and pinion steering gear and
power-assist pump/reservoir. The steering gear and pump/reservoir are connected by flexible hoses.
TESTING
HYDRAULIC SYSTEM PRESSURE TEST
Pump Fluid Pressure Test
1. Disconnect pressure hose and connect pressure gauge/valve between steering pump and steering gear. See
Fig. 1
. Bleed air from system.
2. Open valve fully. Start engine and idle. Turn steering wheel lock-to-lock to increase fluid temperature to
122-140°F (50-60°C). To measure pump fluid pressure, close gauge valve completely.
3. Increase engine speed to 1000-1500 RPM. Ensure pump pressure is within specification. See
HYDRAULIC SYSTEM FLUID PRESSURE SPECIFICATIONS
table. If pressure is not within
specification, replace pump.
CAUTION: DO NOT leave gauge valve closed for more than 15 seconds, or pump may
be damaged.

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
Microsoft
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Fig. 1: Connecting Pressure Gauge (Except 4-Wheel Steering)
Courtesy of MAZDA MOTORS CORP.
Gear Fluid Pressure Test
1. Ensure pump pressure is within specification. To measure steering gear fluid pressure, open gauge/valve
completely. Increase engine speed to 1000-1500 RPM.
2. Turn steering wheel from lock-to-lock. Gauge pressure must be within specification. See HYDRAULIC
SYSTEM FLUID PRESSURE SPECIFICATIONStable. If pressure is less than specification, steering
gear is defective.
HYDRAULIC SYSTEM FLUID PRESSURE SPECIFICATIONS
(1)
Applicationpsi (kg/cm2 )
Miata1109-1209 (78-85)
MPV, MX-6, 626 & 9291067-1138 (75-80)
Protege
2WD1067 (75)
4WD1138 (80)
RX71138-1209 (80-85)
3231067 (75)

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
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LUBRICATION
CAPACITY
POWER STEERING FLUID CAPACITY
FLUID TYPE
Dexron-II or M-III are recommended for all vehicles.
FLUID LEVEL CHECK
Check fluid level with engine off. Remove fluid level gauge on oil pump or reservoir. Check fluid level. Fluid
should be between "L" and "H" marks on level gauge dipstick. If fluid level is low, fill through gauge tube.
Recheck fluid level. DO NOT overfill.
HYDRAULIC FLUID BLEEDING
1. Raise and support front of vehicle. With ignition off, turn steering wheel lock-to-lock several times. Add
fluid as necessary. Repeat procedure until fluid level no longer decreases.
2. Start engine and let idle. Turn steering wheel lock-to-lock 5 times. Check fluid level. Add fluid as
necessary. Continue procedure until fluid is clear of air bubbles and does not decrease in level.
ADJUSTMENTS
POWER STEERING BELT ADJUSTMENT
POWER STEERING BELT DEFLECTION
(1)
(1)Specifications are measured at 1000-1500 RPM, with fluid temperature at 122-140°F (50-60°C).
ApplicationQts. (L)
Miata, MPV & 929.95 (.90)
MX-6 & 626
Electronc Controlled Power Steering (ECPS)1.06 (1.0)
Engine Speed (Sensing) Power Steering (ESPS).95 (.90)
Protege & 323.63 (.60)
RX7.85 (.80)
NOTE: On-vehicle adjustment procedures are not available from manufacturer.
ApplicationIn. (mm)
Miata, Protege & 323
New Belt.31-.35 (7.8-8.9)

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
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REMOVAL & INSTALLATION
STEERING GEAR
Removal & Installation (Miata & MPV)
1. Disconnect negative battery cable. Raise and support front of vehicle. Remove front wheels. Remove
cotter pins and castle nuts from tie rod ends.
2. Using puller, remove tie rods from steering knuckles. Remove steering column intermediate shaft-to-
steering gear pinion shaft bolt. Mark reference lines on pressure pipe fittings.
3. Remove pressure and return hose connections from steering gear. Remove 2 steering bracket-to-frame
mounting through bolts. Remove steering gear and linkage with steering bracket attached from under the
vehicle.
4. To install, reverse removal procedure. Fill and bleed system. Tighten bolts to specification. See
TORQUE SPECIFICATIONS
table. Tighten steering gear-to-mounting bracket bolts (4) in the
following order: left front, right front, left rear, right rear.
Removal & Installation (MX-6 & 626)
1. Disconnect negative battery cable and power steering pressure switch connectors. Raise and support front
of vehicle. Remove front wheels.
2. Remove cotter pins and castle nuts from tie rod ends. Using puller, remove tie rods from steering
knuckles. Remove steerin
g column intermediate shaft-to-steering gear pinion shaft bolt.
Used Belt.35-.39 (8.9-10.0)
MPV
V6
New Belt.28-.30 (7.1-7.6)
Used Belt.30-.32 (7.6-8.1)
4-Cylinder
New Belt.26-.28 (6.6-7.1)
Used Belt.28-.31 (7.1-7.8)
MX-6 & 626
New Belt.31-.36 (7.8-9.1)
Used Belt.35-.43 (8.9-10.9)
RX7
New Belt.43-.51 (10.9-12.9)
Used Belt.55-.63 (14.0-16.0)
929
New Belt.28-.35 (7.1-8.9)
Used Belt.35-.43 (8.9-10.9)
(1)Belt deflection is measured at midpoint between idler pulley and pump, with 22 lbs. (10 kg.) of
pressure applied.

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
Microsoft
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3. Remove pressure and return hose connections from steering gear. Remove mud flap on driver's side.
Remove steering gear mounting bolts. Remove steering gear through wheelwell on driver's side.
4. To install, reverse removal procedure. Fill and bleed system. Tighten bolts to specification. See
TORQUE SPECIFICATIONS
table.
Removal & Installation (Protege & 323)
1. Disconnect negative battery cable. Raise and support front of vehicle. Remove front wheels. Remove
engine undercover. Remove cotter pins and castle nuts from tie rod ends.
2. Using puller, remove tie rods from steering knuckles. Remove steering column intermediate shaft-to-
steering gear pinion shaft bolt. Remove pressure and return hose connections from steering gear box.
3. Remove all accessible steering gear mounting bracket upper nuts and lower bolts. On Protege, support
drive train from above. Loosen stabilizer bar left mounting bracket and remove engine mount
crossmember.
4. Remove transmission control cable clip. Remove transfer case mount nuts. Lower engine gradually until
rear engine mount bolts can be removed. Remove lower left steering gear mounting bolt from between
transaxle and transfer case.
5. On all models, remove steering gear. To install, reverse removal procedure. Fill and bleed system.
Tighten bolts to specification. See TORQUE SPECIFICATIONS
table.
Removal & Installation (RX7)
1. Remove battery. Drain cooling system. Remove fan shroud and radiator. Raise and support front of
vehicle. Remove front wheels and engine undercover.
2. Remove control links and stabilizer bar. Remove cotter pins and castle nuts from tie rod ends. Remove tie
rods from steering knuckles with puller.
3. Remove steering column intermediate shaft-to-steering gear pinion shaft bolt. Remove pressure and
return hose connections from steering gear box.
4. Remove steering gear mounting bolts. Lower steering gear brackets, steering gear and linkage from
vehicle as an assembly.
5. To install, reverse removal procedure. Fill and bleed system. Tighten bolts to specification. See
TORQUE SPECIFICATIONS
table.
Removal & Installation (929)
1. Disconnect negative battery cable. Raise and support front of vehicle. Remove front wheels. Remove
engine undercover. Disconnect pressure and return hose connections in front of steering gear.
2. Drain fluid. Disconnect return hose fitting to control valve. Remove starter for access to control valve.
Disconnect control valve and pressure switch connectors. Remove control valve. Remove cotter pins and
castle nuts from tie rod ends.
3. Using puller, remove tie rods from steering knuckles. Remove steering column intermediate shaft-to-
steering gear pinion shaft bolt. Remove steering gear mounting bolts. Remove steering gear from bottom
of vehicle.
4. To install, reverse removal procedure. Tighten bolts to specification. See TORQUE SPECIFICATIONS

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
Microsoft
Sunday, July 05, 2009 2:10:15 PMPage 5 © 2005 Mitchell Repair Information Company, LLC.

table. Bleed air from system. Check fluid level. Check for leaks. Adjust alignment (if necessary).
POWER STEERING PUMP
Removal & Installation
1. Raise and support front of vehicle. On MX-6 and 626, remove right wheel and splash shield. On all
models remove belt, alternator and hydraulic lines from pump.
2. On Protege and 323, disconnect air cleaner duct and pressure switch. On all models, cap lines to prevent
contamination. Remove bracket-to-pump bolts.
3. To install, reverse removal procedure. Adjust belt tension. See POWER STEERING BELT
DEFLECTION TABLE under ADJUSTMENTS. Bleed air from system. Check for leaks.
OVERHAUL
STEERING GEAR
NOTE: See Fig. 2
-8 for exploded views of rack and pinion steering gears.

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
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Fig. 2: Rack & Pinion Steering Gear (Miata)
Courtesy of MAZDA MOTORS CORP.

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
Microsoft
Sunday, July 05, 2009 2:10:15 PMPage 7 © 2005 Mitchell Repair Information Company, LLC.