I just went down and inspected an exhaust housing tower I had in the basement.
Not sure how the hot exhaust is getting to the front of the housing. The front has the enclosed drive shaft tube. Did you re install the plastic spacer when you did the water pump with an o ring on either side?
Wondering what baffle plate if any you have installed. There were some changes to that model done. Does you model number have a letter suffix after it?
Pulled head. Found lots of carbon. Sorry the gasket ripped when the head came off. If it would have stayed in one piece maybe would have helped with the detective work. I didnt see part #2 plate? Could that be causing the exhaust to burn the housing, or just a bad gasket?
Good point Frank. Will dig around. Checked all cooling passages, tubes etc with compressed air and they all flowed well. I'm also thinking gasket on exhaust housing under powerhead was shot allowing the hot exhaust gas to move to the front of the housing instead of dumping the exhaust out the back of housing under the pistons?
Boy, that is cooking, and it doesn't appear that the engine is overheating.... Have you removed that crazy SS cover with the two screws? Maybe all the carbon has covered ports in there that is causing the hot exhaust to back up...Don't know what would make it get so hot on the front of the housing though, perhaps the gasket was leaking directing hot exhaust to that area where it was having a hard time escaping....