Oil Metering Pump Failure
Symptoms
Without lubrication, the apex seals run metal-on-metal against the rotor housing. Wear accelerates catastrophically. The engine may seize.
Cause
The oil metering pump (OMP) injects small quantities of two-stroke oil directly into the combustion chamber to lubricate the apex seals. The pump is mechanical, driven by the engine. After 50+ years, the pump's internal seals can fail, the delivery lines can crack or clog, and the pump itself can seize. Some previous owners may have disconnected the pump and switched to premix (adding oil directly to the fuel), which works but requires discipline, forget to premix and the engine is destroyed.
Fix
If the OMP is original and functioning, maintain it.
Replace the delivery lines with new silicone hose.
If the pump is not functioning, either rebuild it (parts are scarce) or commit to premix operation at 1:200 ratio.
If running premix, label the fuel filler prominently and never let anyone else fuel the car without instruction.
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