🏷️ Basic Information

Make:

Mazda

Model:

RX-4

Year:

1977

Chassis Code:

LA2

Engine Code:

12A

👋 Introduction

Positioning:

The Mazda RX-4, introduced in the mid-1970s, positioned itself as a stylish, sporty, and technologically advanced alternative in the compact/intermediate class, notably for its rotary engine.

Competitors:

Competed with established Japanese and American sedans and coupes, including models from Datsun (Nissan), Toyota, Ford, and General Motors, often differentiating itself with its unique rotary powertrain.

Distinctive Attributes:

Rotary engine (Wankel), distinctive styling, often available as a coupe, sedan, or wagon, sporty handling characteristics.

Value:

This manual is critical for maintaining and repairing the unique 12A rotary engine, providing specific procedures and specifications not found in generic manuals. It empowers owners and technicians to service this iconic Japanese classic.

📋 Manual Details

Coverage Scope:

All models and all repairs A-Z

Page Count Estimate:

Approximately 500-700 pages (typical for a comprehensive factory service manual of this era)

Type:

Factory Service and Repair Manual

Language:

English

Format:

Printed

📖 Manual Coverage

Engine:

Rotary engine (12A) theory of operation, disassembly, inspection, assembly, timing, lubrication, cooling

Fuel System:

Carburetor(s) (e.g., Hitachi, Mikuni depending on market), fuel pump, fuel lines, emissions control systems (e.g., air injection, thermal reactor)

Ignition System:

Distributor, ignition coils, spark plugs, wiring, timing specifications

Transmission:

Manual transmission (e.g., 4-speed, 5-speed) and Automatic transmission (e.g., 3-speed) overhaul, adjustment, fluid specifications

Drivetrain:

Clutch, driveshaft, differential, rear axle assembly

Suspension:

Front suspension (e.g., MacPherson strut), rear suspension (e.g., leaf spring or coil spring depending on body style), shock absorbers, springs, bushings

Steering:

Steering gearbox, steering column, tie rods, power steering system (if equipped)

Brakes:

Front disc brakes, rear drum brakes, brake lines, master cylinder, wheel cylinders, parking brake system

Electrical System:

Battery, alternator, starter motor, lighting, gauges, wiring diagrams, fuses, relays, switches

Body And Chassis:

Body panel removal/installation, door mechanisms, glass, seats, interior trim, chassis lubrication points

Heating And Air Conditioning:

HVAC system components, ducting, controls, refrigerant (if equipped)

Maintenance:

Oil changes, filter replacements, lubrication, spark plug replacement, belt adjustments, fluid checks and top-offs

Troubleshooting:

Diagnostic charts, symptom-based troubleshooting for all major systems

Repair:

Detailed step-by-step repair procedures for component overhauls, replacements, and adjustments

Overhaul:

Complete engine, transmission, and differential overhaul procedures

Specifications:

Torque specifications for all fasteners, clearances, alignment settings, and performance data

Depth:

Comprehensive, technician-level detail suitable for dealership mechanics and serious enthusiasts. Includes internal component specifications and rebuild procedures.

📊 Manual Specifications

Digital Format:

N/A (as it is a printed manual)

Quality:

High-quality reproduction of original factory documentation, including clear diagrams and illustrations.

Binding:

Likely comb-bound, spiral-bound, or stapled for ease of use in a workshop environment.

Paper:

Durable, slightly glossy paper suitable for workshop conditions.

⚙️ Engine Specifications

Engine Type:

Two-rotor Wankel (Rotary)

Engine Displacement:

1146cc (equivalent to approximately 2292cc piston engine displacement for tax/classification purposes)

Bore X Stroke Equivalent:

N/A (Rotary engine design differs from piston engines)

Rotor Housing Design:

Epitrochoid housing

Horsepower Approx:

90-110 HP (depending on emissions equipment and market)

Torque Approx:

100-120 lb-ft (depending on market)

Carburetion:

Single or twin downdraft carburetors (e.g., Hitachi DCZ, Mikuni Solex)

Fuel Type:

Unleaded gasoline (post-catalytic converter models)

Type:

Water-cooled

Oil Type:

Specific rotary engine oil or high-quality conventional oil meeting API SF or SG service classification (refer to manual for exact specification).

Ignition Timing:

Specified in degrees Before Top Dead Center (BTDC), adjustable via distributor. Critical for rotary engine performance and emissions.

Systems:

Air injection reactor (A.I.R.), exhaust gas recirculation (EGR), thermal reactor (in earlier non-catalytic converter models).

🔧 Transmission

Type:

4-speed manual

Type:

3-speed automatic (e.g., Toyo Kogyo AT)

Clutch Type:

Dry single plate

Gear Ratios:

Detailed in the manual for both manual and automatic transmissions.

Manual Transmission Fluid:

API GL-4 hypoid gear oil (e.g., SAE 75W-90 or 80W-90, consult manual for specific viscosity and capacity)

Automatic Transmission Fluid:

Dexron-II or equivalent (consult manual for specific type and capacity)

📐 Dimensions

Body Styles:

Coupe, Sedan, Wagon

Wheelbase:

Approx. 98.0 - 104.3 inches (varies slightly by body style)

Length:

Approx. 165.0 - 175.0 inches (varies by body style)

Width:

Approx. 65.0 - 67.0 inches

Height:

Approx. 52.0 - 55.0 inches (varies by body style)

Curb Weight:

Approx. 2300 - 2700 lbs (varies by body style and equipment)

Wheel Bolt Pattern:

4x110mm

Standard Tire Size:

Typically 175SR13 or 185/70R13 (refer to manual for specific fitments)

🛡️ Safety Features

Crash Test Data:

No specific NHTSA or IIHS ratings available for this model/era. Safety features typical of the period.

Braking System:

Front disc brakes, rear drum brakes. Power assisted brakes often standard or optional.

Seatbelts:

Lap belts (front), lap belts (rear). Shoulder belts may be standard or optional depending on market and build date.

Windshield:

Laminated safety glass.

💡 Technology Features

Audio System:

AM/FM radio, often with an 8-track player or cassette adapter compatibility. Speaker count typically 2 or 4.

None:

No electronic driver assistance systems typical of modern vehicles. Focus is on mechanical systems.

None:

No modern connectivity features like Bluetooth or USB.

🔧 Maintenance

Engine Oil Change:

Typically every 3,000 miles or 3 months (refer to manual for specific recommendation).

Air Filter Replacement:

Every 12,000 miles or 12 months.

Spark Plug Replacement:

Every 12,000 miles for standard plugs; specific rotary plugs may have different intervals. Manual lists specific plug part numbers and gaps.

Coolant Type:

Ethylene glycol-based antifreeze, typically a 50/50 mix with distilled water. Consult manual for specific type and capacity.

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid.

Apex Seals:

Wear or failure of apex seals is a common concern with rotary engines, leading to loss of compression. Manual covers inspection and replacement.

Carbon Buildup:

Carbon buildup in rotor housings and exhaust ports can affect performance. Manual provides cleaning procedures.

Oil Consumption:

Rotary engines naturally consume some oil as part of their lubrication system. Excessive consumption indicates a problem. Manual details checks.

Carburetor Tuning:

Carburetors may require periodic tuning due to their complexity and sensitivity to vacuum leaks or wear. Manual provides adjustment procedures.

📚 Vehicle History

Mazda Rotary Introduction:

Mazda's commitment to the Wankel rotary engine began in the late 1960s with the Cosmo Sport, establishing a unique niche in the automotive world.

Rx Series Development:

The RX-4 followed the RX-2 and RX-3, continuing the sporty lineage and featuring a more refined and powerful 12A rotary engine, often with improved emissions control.

Production Years:

1972-1978 (RX-4 designation in some markets, often preceded by RX-2 and followed by RX-7 variants)

Manufacturing Location:

Japan

🏆 Awards & Recognition

Rotary Engine Recognition:

The rotary engine itself has received recognition for its engineering innovation and smooth operation, though its practicality for mass-market adoption faced challenges.

Performance Reviews:

Contemporary reviews often praised the RX-4's distinctive engine note, sporty driving feel, and unique character, positioning it as a performance-oriented alternative.