DO NOT RUN DIESELS WITH TOO MUCH OIL!! THEY CAN, AND HAVE, RUN AWAY.
The problem is that when you have too much oil in a diesel the blowby, cause by the piston on the downward stroke, causes oil to enter the combustion chamber and is ignited during the compression stroke.
The result is an uncontrollable source of fuel and the diesel will run away. You will not be able to shut it off and the engine usually destroys itself as RPMs get way off scale - up to 5000, by the way!
The only way to shut it off it to place a hard object (not your hand) over the air intake and deprive the howling monster of air. But when you hear one run away you'll probably be cowering in the cockpit in full fetal position.
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