300/440/550 cooling line popped off?

[myblackz28]

my brother and i finally went riding yesterday and after about an hour he said he hit a wave and the ski suddenly seemed to bog down. the water is probably around 35 to 40 degrees, idk if that would make a deference on how long it would last without water. he went straight for shore and only made it about 2-300 feet i would say. there was smoke rolling out the hood. we towed it in and when we got it to shore i noticed the cooling line came off of it. we were having battery problems so it wont crank over. i had to go to class so i wasnt able to check it out so i was curious what everyone here thinks.
do you think the engine is blown or does that engine have some kind of overheating sensor that it shuts the engine down if it gets to warm.
i forgot to mention it is a '84 550 bone stock as far as i know. i bought it from an older guy that had it for 17 years and had never done any work to the engine, just had it tuned and the basic upkeep.

 

[jet750]

No over heat sensor, the smoke coming out of the hood was the exhaust backing up through the motor and cooling line because there was no water in the motor. It should be fine.

 

[jetski9010]

The cooling line could have came off and been spraying water at the engine causing steam which is maybe what you had seen when you pulled the hood off. Get that battery problem fixed then see if it will crank. Then check the compression and see what you got? If its anywhere in the 115 PSI and up range you should be good to run with no problems.