failed u joints?

[eddie rosario]

hello all. i am getting a 2006 240 sundancer this friday and the boat i am trading in is a 1978 srv 240cc.the old gal was running fine but needed to get into the 21st century.had water in the fuel and had to get towed in a couple of weeks ago.was starting to make some rumbling noises before it quit.changed out the fuel water seperator and started it up.more rumbling.so now i shut it off and try to start again and the engine will not turn over.seems like the u joints failed right there.tried to turn the engine over by hand and was pretty hard to do.does this seem logical to you guys?i am pulling it out on wendsday to see if i am right.not too big of a deal if that is the problem.can't trade the boat if i can't get this fixed.thanks for all the advice,eddie