Originally Posted by Domenic
... It's common to start engines that dicharge water through the exhaust
with the water flow off. It takes more than a minute for an engine to even warm up.
I certainly wouldn’t
endorse the idea, as a normal routine
(“always”) starting procedure.
However, continued cranking of an engine can cause the muffler
to fill with water, and back-flow into the engine (causing hydrostatic lock, or hydrolock*). Only shut off the water supply to an engine that won't start, and open the valve as soon as it does start.
* The water in the cylinders, being incompressible, locks up the motor
so that it will not turn over. Other indicators are a rising oil level (from water finding its way into the crankcase), or creamy colored emulsified oil, the result of water being mixed with the oil, sometimes with beads of water, on the dipstick or inside the oil filler cap. In any event, you must get the water out of the cylinders (preferably immediately) prior to cranking.