302 Homan Moody problems

I have a 1973 Martinique which I recently ran for about 15 minutes, and it started slowing down like someone had pulled the throttle back to idle. Pumped the throttle and it picked up speed again(making it back to my dock).

Later, I started the engine with the motor cover up to look for anything unusual. Motor idled for a couple of minutes then backfired through the carb with enough force to blow the hose that goes from the carb base to the PCV valve off!

I floated the boat on the trailer. Once on the trailer, I noticed the exhaust flap on the right exhuast had been sucked back into the exhaust pipe.

I removed the spark plugs, grounded the coil wire, took the belts off the water pump and turned the engine over. On the right side, it pumped water out of the spark plug holes, other side was dry. Also, there were no signs of water in the oil.

Would like any sugestions on how to proceed next.

Thanks in advance for any help!

Sounds like an engine rebuild is in your near future.