to prevent this kind of damage when a head gasket is blown..
i drain the cooling system . on V6 and V8s.. i have been known to pull the thermostat and use the wet or dry shop vacuum to pull as much of the coolant out of the block as possible.. there are block drains on a lot of cars.. but not every one has them on both sides..
my trick. with NO COOLANT.. i start the engine for ONE minute max.. this will blow out any coolant that has gotten into the cylinders and heat the engine just enough to dry it out hopefully..
i also will spray or have somebody spray WD40 into the throttle body or thru a vacuum just just before i shut it off at the end of the first minute.. i also will drain the engine oil and filter.. putting in fresh oil and cranking the engine with the ignition disconnected and the filter off. for a few seconds then screw the new filter on and crank again till the oil light goes out. this usually gets rid of much of the coolant that may be sitting in the oil pump and galleys. you can also start the engine again after this but keep it under 1 minute. big note on the steering wheel.. NO COOLANT.. don't start.. ask so and so..
that engine is TRASHED.. more than likely.. the cylinder walls will probably be etched that it will consume oil at several hundred miles per quart if it does not smoke and kill the cats with excess oil consumption.
this is just stuff i do .. i am NOT saying that you should all do it.. i also won't do a head gasket without using hylomar.. or permatex 85420 which is actually hylomar.. but again.. i am lazy.. i don't want to do it a second time for free.. i have not had a failure since i started doing it in 1993. that's probably only 200 head jobs and 40 engine jobs that i assembled. many of you have 10 times that.