Help - I Think I Blew My Transmission

I own a 1981 Southwind (Ski Nautique) with a 351 engine in excellent condition for it's age. The transmission is a Velvet Drive 10-17-003 (ASI-71B)with a 1:1 drive ratio.

I had the boat overloaded with people yesterday and tried to get it up on a plane. As it was approaching a plane, then something immediately let go and the engine over-reved and I shut it down immediately. There is now no power transmission in either forward or reverse. The prop shaft does not turn in either forward or reverse but it spins freely. There is a minor mechanical grinding noise that seems to come from the vicinity of the transmission.

What do you think happened? Did I blow the transmission or is there linkage between the engine shaft and transmission that let go. Where is the best place to get parts, either new or rebuilt?

Many thanks for your advise.

Based on it going all the sudden I suspect you need a new drive damper or you need a new damper and a new transmission or a major rebuild. Assume the best, buy the damper and when it shows pull off the transmission and hope for the best

So pete beat me to it but I am claiming bonus points for the link

C'mon guys you know what he means! And whether it's a Skier or San Juan, the model wouldn't make a difference as to the problem. But as a side note, in the '80's there was either a 70's Ski Nautique or a Martinique on the Butler chain with factory graphics labeled a Southwind. So you could easily call that a Southwind (Ski Nautique). The guy must've picked up the wrong stencil that day.

Cudatique!