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MOTRS

Cosmo Sport (110S)

1967-1972 / Coupe / Japan

All Cosmo Sport (110S) problems All workshop issues
Minor Body and Structure

Rust, Everywhere

Symptoms

Perforation of body panels, structural weakening of the floor, sills, and load-bearing members. Bubbling paint, soft spots, and visible corrosion.

Cause

The Cosmo Sport is a 1960s Japanese car. Corrosion protection standards were rudimentary. Any car that has lived outside a climate-controlled garage will have some degree of rust. Australian-delivered or Australian-resident cars (of which there are vanishingly few) will have additional exposure to coastal air, humidity, and road conditions. - Sills and rocker panels: Structural members that support the floor and body. Perforation here is serious. - Floor pans: Moisture intrusion from above (leaking seals) and below (road spray). - Rear wheel arches: Road spray accumulates in the inner arch. - Boot floor: Water collects in the spare tyre well. - Windscreen surround: Deteriorated rubber seals admit water. - Door bottoms: Blocked drain holes cause rust from inside.

Fix

Specialist panel fabrication.

There are no reproduction panels for the Cosmo Sport.

Every repair is bespoke metalwork.

Cost varies enormously, budget $5,000-20,000+ for significant rust repair, depending on severity.

Cost mentioned in fix
budget $5,000-20,000+ for significant

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// More Cosmo Sport (110S) problems

Other known issues

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

Apex Seal Wear

Loss of compression, reduced power, difficulty starting (especially when cold), blue-white exhaust smoke, and eventually misfiring and inability to idle. A rotary engine with worn apex seals is an engine that needs a rebuild, there is no halfway measure.
Common Engine, 10A Twin-Rotor (982cc)

Hard Cold Starting

The engine cranks extensively before firing when cold. May require multiple attempts. Once warm, starting is normal.
Minor Engine, 10A Twin-Rotor (982cc)

Oil Metering Pump Failure

Without lubrication, the apex seals run metal-on-metal against the rotor housing. Wear accelerates catastrophically. The engine may seize.
Critical Engine, 10A Twin-Rotor (982cc)

Cooling System Inadequacy

Engine overheating, particularly in traffic or on hot days. The temperature gauge climbs steadily, coolant may boil over, and in extreme cases the engine suffers heat-related damage (warped housings, blown coolant seals).
Common Ignition System

Points and Condenser Degradation

Misfiring, rough running, difficulty starting, inconsistent idle.
Minor Ignition System

Spark Plug Fouling

Misfiring, rough idle, loss of power. Plugs come out with heavy carbon or oil deposits.
View all 10 Cosmo Sport (110S) problems