Here is somebody who has heard of it:
Ray: ...what old-timers used to do with kerosene. They used to run a mixture of oil and kerosene into the engine to try to break up the gums and varnishes. But they did it with the engine running. And if they were lucky, they'd shut off the engine just before the kerosene completely croaked the engine. My brother used to do this with the car parked right outside the junkyard gates. That way, if his timing was off, he could just push the car in.
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