Pressure Sealing A Block
 

Saw this on H&H Facebook page. It's news to me. Maybe others have heard of it. "H&H Flatheads:
its a cast iron resin heated up to 180 degrees and pumped through the block under pressure."

Re: Pressure Sealing A Block
 

if you get the rebuild book written by H they called it a ceramic coating to seal the block

Re: Pressure Sealing A Block
 

Yes, I've seen this on their website, too, and was curious. Sounds like a great way to make a slightly cracked block usable or to seal up any unrepairable or inaccessible pinholes.