Positioning:
The Mazda RX-4 was positioned as a stylish and sporty compact car, targeting drivers who appreciated unique engineering and a blend of performance and practicality. It was a distinctive alternative in its segment.
Competitors:
Competed with vehicles like the Datsun 510/710, Toyota Corona, Ford Pinto, and Chevrolet Vega, but differentiated itself with its rotary engine technology.
Unique Selling Points:
Its primary USP was the advanced Wankel rotary engine, offering a smooth, high-revving power delivery and a unique driving experience compared to conventional piston engines of the era.
Powertrain:
Rotary Engine (12A), Lubrication System, Cooling System, Fuel System, Exhaust System
Drivetrain:
Transmission (Manual & Automatic), Clutch, Driveshaft, Differential, Axles
Chassis:
Suspension (Front & Rear), Steering System, Brakes (Front & Rear)
Electrical:
Ignition System, Charging System, Starting System, Lighting, Instrumentation, Wiring Diagrams
Body:
Exterior Body Panels, Interior Trim, Glass, Doors, Locks, Seats
Maintenance:
Scheduled Maintenance (oil changes, filter replacements, tune-ups), Inspections, Lubrication
Diagnostics:
Troubleshooting Guides, Symptom-Based Diagnostics, Component Testing
Repair Rebuild:
Engine Rebuild Procedures, Transmission Overhaul, Brake System Repair, Suspension Component Replacement
Installation Adjustment:
Component Installation, Timing Adjustments, Carburetor Tuning, Electrical Component Replacement
Depth:
Comprehensive: Covers basic maintenance to full engine and drivetrain rebuilds. Includes detailed diagrams and torque specifications.
Engine Type:
Mazda 13B Rotary (often referred to as 12A in the RX-4 context, though technically it was a variant of the 13B series)
Engine Code:
12A (early designation for the RX-4 variant)
Displacement:
1146 cc (69.9 cu in) - equivalent to approx. 2292 cc conventional piston engine displacement due to rotary engine design.
Horsepower:
Approx. 90-100 hp @ 6000-6500 rpm (depending on market and emissions controls)
Torque:
Approx. 100-110 lb-ft @ 3500-4000 rpm
Carburetion:
Two-barrel downdraft carburetor (e.g., Hitachi) or potentially a single two-barrel in some configurations.
Fuel Type:
Unleaded Gasoline (as mandated by emissions regulations of the era)
Cooling Type:
Water-cooled, pressurized system
Oil Type:
API SF or SG classification, SAE 10W-30 or 10W-40 recommended. Specific rotary oil additive might be recommended for pre-mix or separate injection.
Spark Plugs:
Specific long-reach, single-electrode spark plugs required for rotary engines (e.g., NGK BP6ES or equivalent).
Transmission Type:
4-speed manual transmission
Transmission Type:
3-speed automatic transmission (Mazda's 'Roto-Hydra-Matic')
Clutch Type:
Single dry plate, hydraulically actuated clutch for manual transmission.
Manual Transmission Fluid:
GL-4 gear oil, SAE 75W-90 or 80W-90
Automatic Transmission Fluid:
Dexron III or equivalent ATF
Wheelbase:
Approx. 98.4 inches (2499 mm)
Length:
Approx. 166.1 inches (4219 mm)
Width:
Approx. 64.2 inches (1631 mm)
Height:
Approx. 53.5 inches (1359 mm) for Coupe, slightly higher for Sedan/Wagon
Curb Weight:
Approx. 2300-2500 lbs (1043-1134 kg) depending on body style and equipment.
Gross Vehicle Weight Rating:
Not explicitly stated, but typically around 3200-3400 lbs.
Crash Test Results:
No official government crash test data available for this era and model as standardized testing was not as prevalent.
Brakes:
Front Disc Brakes, Rear Drum Brakes. Optional power assist.
Seatbelts:
Lap and shoulder belts (front), lap belts (rear).
Steering Column:
Collapsible steering column (standard feature).
Audio System:
Typically a basic AM/FM radio, often with an 8-track player or cassette tape adapter as an aftermarket option.
Instrumentation:
Analog gauges including speedometer, tachometer, fuel level, coolant temperature, oil pressure, and voltmeter.
Features:
Limited to basic power steering (if equipped) and power brakes (optional). No electronic driver aids present.
Features:
No integrated connectivity features. Relied on aftermarket radio installations for enhanced audio.
Oil Change Interval:
Every 3,000 miles or 3 months, whichever comes first. Rotary engines require frequent oil changes due to their design.
Tune Up Interval:
Recommended every 15,000 - 20,000 miles, including spark plug replacement and ignition timing adjustments.
Rotor Apex Seal Life:
Variable, but generally considered to be around 75,000 - 100,000 miles before potential rebuilding or replacement.
Engine Oil Capacity:
Approx. 4.5 quarts (4.3 liters) with filter change. Specific rotary oil might be required for injection systems.
Coolant Capacity:
Approx. 7.0 quarts (6.6 liters)
Brake Fluid:
DOT 3 or DOT 4 brake fluid.
Apex Seals:
Wear of apex seals is a common concern in high-mileage rotary engines, leading to loss of compression and performance. Requires engine rebuild.
Carburetor:
Carburetor wear and adjustment issues can lead to rough idling, poor fuel economy, and starting problems.
Ignition System:
Rotary engines are sensitive to ignition system health. Worn distributor cap, rotor, spark plug wires, or faulty ignition coils can cause misfires.
Oil Consumption:
Rotary engines inherently consume a small amount of oil as part of their lubrication process. Excessive consumption can indicate seal wear.
Rotary Development:
Mazda's commitment to the Wankel rotary engine began with the NSU license and culminated in iconic models like the Cosmo, RX-2, RX-3, and the RX-4, showcasing their unique engineering prowess.
Predecessors:
The RX-4 succeeded the Mazda RX-3, inheriting its rotary engine technology and sporty compact car lineage, while offering updated styling and improved refinement.
Successors:
The RX-4 was followed by the more aerodynamically styled Mazda RX-7 (SA22C), which shifted the focus to a pure sports car experience.
Production Years:
1972-1978 (for the Mazda RX-4, with the 1975-1977 range being the core focus of this manual)
Manufacturing Location:
Japan
Notable Awards:
While the RX-4 itself may not have specific awards, Mazda's rotary engine technology was widely recognized for its innovation and performance, contributing to the brand's growing reputation in the automotive world during this period.
Automotive Press Reviews:
Generally received positive reviews for its unique engine, sporty handling, and stylish design, positioning it as a driver's car.
