R100 (Familia Rotary)

1968-1973 / Coupe / Japan

All R100 (Familia Rotary) problems All workshop issues

Common Fuel System

Fuel Tank Corrosion

Symptoms

Restricted fuel flow, debris in the fuel system, fuel leaks from the tank.

Cause

Internal corrosion of the steel fuel tank, accelerated by water contamination and ethanol-blended fuels. Rust particles from the tank circulate through the fuel system, clogging the carburettor and causing lean spots.

Fix

Remove, inspect, and seal the tank (POR-15 or Kreem tank sealer).

Install an inline fuel filter between the tank and carburettor.

Replace corroded fuel lines with ethanol-compatible hose and fittings.

Cost: $200-500 for tank restoration; $50-100 for lines and filter.

Cost mentioned in fix

Cost: $200-500 for tank$50-100 for lines

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// More R100 (Familia Rotary) problems

Other known issues

Common Fuel System

Carburettor Deterioration

Poor idle quality, flat spots during acceleration, hesitation off idle, fuel leaks from the carburettor body, flooding, or lean running.

Minor Engine, 10A Twin-Rotor (982cc)

Apex Seal Wear

Gradual loss of compression, resulting in reduced power, increasingly difficult cold starts, blue-white exhaust smoke (burning oil), and eventually rough idle, misfiring, and inability to maintain running at low RPM.

Minor Engine, 10A Twin-Rotor (982cc)

Oil Metering Pump Failure

The apex seals lose their lubrication source. Wear accelerates dramatically, and the engine may seize if run for extended periods without lubrication.

Critical Engine, 10A Twin-Rotor (982cc)

Cooling System Inadequacy

The engine overheats, particularly in traffic, on hot days, or under sustained load. The temperature gauge climbs, coolant may boil over, and the engine suffers heat distortion or blown coolant seals.

Common Engine, 10A Twin-Rotor (982cc)

Exhaust Port Gasket Leaks

Exhaust gas leaks at the junction between the exhaust manifold and the engine's exhaust ports. Audible ticking sound that increases with RPM. May cause exhaust fumes in the cabin.

Minor Body and Rust

Floor Pan Corrosion

The floor pans perforate, weakening the car's structure and allowing moisture and exhaust fumes into the cabin.

View all 13 R100 (Familia Rotary) problems