R100 (Familia Rotary)

1968-1973 / Coupe / Japan

All R100 (Familia Rotary) problems All workshop issues

Minor Body and Rust

Floor Pan Corrosion

Symptoms

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

Cause

Moisture trapped under carpets, combined with road spray from underneath. The R100's floor has minimal corrosion protection by modern standards. Australian humidity and occasional flooding accelerate the process.

Fix

Cut out corroded sections and weld in new steel.

This is not a patch-and-fill job, the floor pans are structural.

A good panel beater or fabricator can manufacture repair sections.

Cost: $1,000-3,000 per area, depending on severity.

Cost mentioned in fix

Cost: $1,000-3,000 per area

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// More R100 (Familia Rotary) problems

Other known issues

Minor Body and Rust

Sill and Rocker Panel Rot

The box-section sills that run along each side of the car corrode from the inside, eventually perforating and losing structural rigidity.

Common Body and Rust

Rear Wheel Arch Corrosion

Rust develops in the inner and outer wheel arches, spreading from the inside.

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.

View all 13 R100 (Familia Rotary) problems