nook
+1y
I don't blame you for not wanting to have to weld on a fresh ceramic finish, I never contacted Thorley about it, figured it was an isolated case but apparently not, have seen numerous posts regarding the same issue on other toy sites, this has been several years back so could have been a certain production batch that was shipped out, who knows, stranger stuff has happened. I had a friend who installed a major manufacturer camshaft in his 22r, couldn't get it to run so called me asking for help, figured maybe he had it a tooth out or something so checked it out and that was OK, ended up I degreed the cam in and came up like 17 degrees retarded, checked several times and came up with the same results, the cam was ground out of whack or indexed wrong, called the manufacturer and was told NO WAY, those are all computer done and couldn't be off, well your computer must be tits as it ain't right, they said to send it in and they would check it, sent it in, about a week later got a brand new cam in the mail, no charge HMMM! new one went in and degreed just right, damn disgruntal computers.
Anyhoot back to the header, I was able to find the leak by studying the gasket crush and by small discoloration where it was blowing through, after that just placing the new gasket on the flange and head and fine point felt marker around the gasket port showed where it was aligned for sealing against each side. Hopefully it was just an early bad batch and won't effect yours at all.