Hard Cold Starting
Symptoms
The engine cranks extensively before firing when cold. May require multiple attempts. Once warm, starting is normal.
Cause
Multiple factors combine. The 10A's apex seals contract when cold, reducing compression below the threshold needed for reliable ignition. The manual choke system requires precise operator technique. The ignition system (points and condenser in original specification) may be weak. The fuel system (carburettor) may not be delivering an adequately rich mixture for cold starting. And after 50+ years, every component in the fuel and ignition chain has degraded.
Fix
Systematic approach: verify compression first (if compression is low, no amount of ignition or fuel work will fix starting).
Clean or rebuild the carburettor.
Replace points and condenser (or convert to electronic ignition, a common and reversible modification).
Ensure the choke mechanism is functioning correctly.
Verify the starting enrichment circuit.
Many owners install a small electric fuel pump to ensure the carburettor bowls are full before cranking.
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