Well, I guess you've learnt your lesson and got away with it!
For those who didn't catch on what happened: Never connect a pressurized hose to your water intake - the pressurized water will flow up the wet exhaust in the absence of exhaust pressure and into whichever cylinder has an open exhaust valve. Same reason you shouldn't endlessly crank an engine that doesn't want to start (the cranking still turns the raw water pump). Water is not compressible, so when cranking the engine with water in a cylidner, something else will break, in this case luckily only the starter, worst case you will end up completely destroying the engine.
I met a guy with a classic motorboat which had a long, gently sloping exhaust run. When lifting the boat, the stern got raised higher than the bow and the water sitting in the exhaust hose ran back into one engine. Upon cranking it (without knowing about the water in the cylinder), the pushrods bent and he was lucky it was just that. Surprisingly, the engine ran like that - a bit rough and on 3 cylinders
Taking the intake hose off the seacock and hanging it in a bucket that is being filled by the boatyard hose is fine.