At 10:49 AM 5/24/2006 -0400, Bill Spohn wrote this article:

Just got another note from a guy with cracked cam covers on a Twincam (centre stud) asking me about how to make the covers seal without putting so much pressure on the nuts that you crack the admittedly weak cover.

First, take the cracked cover and have a bead of weld run over the crack to repair it.

Buy some Stat-o-seals - these are alloy washers with an O-ring crimped into it. While you are at it, buy a set of V12 Jaguar cam cover nuts - they are identical to the original Twincam nuts, except for being chrome instead of rather rough steel.

Cut some new gaskets from rubberized cork material. Glue them onto the cam covers with contact cement.

Take a bunch of flat washers that fit over the cam cover studs. Stack just enough on the centre stud so that the gasket will compress - in other words stack them until the new cork gasket is just clear of the sealing area at the outside of the cover and then remove one. This will give you enough pinch to seal the oil in without being able to crush and crack the cover again.

The Stat-o-seals deal with the other problem - a big part of the cause of cracked covers. The factory used copper washers that didn't seal very well - so when the leaks started, people reefed down on the nuts, and ended up cracking the covers. These seals work at much lower pressure and work much better than the copper ever did and are all but invisible in place. Concours nuts can get out their paint brushes and turn the aluminum edge to copper colour if they really need to.