Does anyone know if these are of use or ornament or neither. Carrying on from my post on the below thread. http://thelatebay.com/index.php?topic=14678.0 I came across a seating/compression of the seal issue on me mates van that was causing all sorts of valve problems. ended up ditching them and using a smear of instant gasket instead, I don't know if I needed to do this and Im not quite sure what they do ,I have noticed there is no recess for them on some heads.
If you mean the little rubber donuts...they stop oil seepage down the threads of the rocker studs. As I recall, on original heads the threaded stud holes go through to the outside world, so in theory a bit of oil could leak down the studs. On my replacement Autolinea heads, the threaded holes were blind (didn't emerge from the head casting), so the seals weren't strictly necessary. Just depends on the casting type - Autolinea obviously fixed this small issue. In fact, their castings were better than the VW originals, IMO. If there's no recess and the studs screw into blind holes in the casting, you don't need the seals. They shouldn't in any way affect the seating of the rocker mountings or geometry. If there are no recesses in the casting, I can imagine fitting seals will prevent the rocker assembly sitting properly. Make sense?
