Sorry about the crack.....I've seen worse.
I had an engine with a cracked cylinder.
I was advised that super glue is a good
alternative so I tried it with success. Just
be careful of the piston's position. I don't
think the glue will make it all the way in.
Just don't flood it with glue - less = no mess!
Or, call Jensen and ask to speak with Andy.
He does a great job of soldering engine parts.
I had a cylinder that split off the steam chest
and the prior owner tried

to glue it together.
A real mess. Andy took the whole engine and fixed
it perfectly. It is now a sweet runner.
Good Luck,
Wayne