The pressure testing that I mentioned is a standard cylinder head pressure test that any well equipped head shop should have. That's why I'm 99% sure that if the head is leaking it will show up in No.3 combustion chamber when I do get the head off.
In the mean time when I get a chance I'm gonna do a cylinder leak down test just to see if I can nail it before I tear it down. I have to machine a new adaptor for the 14mm plugs, the only ones I've got made up are for the tapered plugs and the 18mm plugs that are in the Lycoming in my Pitts. I used to do a leak down test on it every time I did my annual inspection.
Anyway you look at it, it's a bummer.
Before I decided to go ahead and use this head I got three other ones (the same casting number) and two of the three had more cracks than my original head, the third one had no cracks but did have some very large ugly deep pits on a couple of cylinders which showed up once we got it out of the dip tank. I sunk another $450 into it so I’m hoping that one should be OK.
Denny Graham
Sandwich, IL

Denny G
Sandwich, IL