4
« on: June 10, 2016, 14:02:46 »
Hello Gary,
I appreciate your not wishing to embarrass me in public - that was very thoughtful. As I cannot recall the 8thou bit - perhaps I missed that or just wasn't listening - I won't argue although I feel certain that I would have expressed concern because we build all our engines (over sixty to date) to 20thou for a lot of very good reasons. One of these was because in around 2003 I quite deliberately built an engine for my own car with 9thou protrusion just to see what would happen. And what did happen was that all was well for a short while and then the engine started misfiring after ticking over and eventually went down to five and then four cylinders and the sump began filling with water, so I reset the liners at 20thou and cured the problem. By the way and in case anyone wants to try this trick, I did this with the engine in the car with the head off and by pulling the liners off the pistons and then refitting them on top of thicker fig-of-eight gaskets. Good fun if you've nothing better to do and don't mind wrecking your finger nails whilst feeding the rings into the bottoms of the liners!
I would definitely contest the matter of AC's stated correct liner protrusion because, although this figure is given in some of their literature (I've just looked), over the years they issued several different and gradually increasing figures, eventually arriving at an astounding 30thou. And no, just in case anybody asks me to prove that, I am not going to because I can't remember where I saw it.
However, all this is likely to prove fairly academic ere long as, after much protracted experimentation, we hope to have our new, low cost, re-usable head gaskets in production soon. Hopefully Robin's gasket will have done the trick and you won't need one.
Best regards,
Rod