Hi folks, just wondered if anyone uses a torque setting for the Cylinder base nuts on the M20,always get a weep of oil from here, checked them with spanner the other day and took up a little so wondered how much I can give them, thank you for any comments, Ian
It's hard to get a torque wrench in there even with a crowsfoot spanner, so basically just tighten them as much as you can, you'd be hard pushed to strip one with a normal spanner, if you do, there is something up with the stud or nut. I sometimes tap them round another 1/4 turn with a copper hammer when I've tightened them as much as I can with the spanner
I use silicone on the gasket and then just tighten them well. One thing to check when assembling the M and B Series engines is that the two studs that hold the cases together are straight (the mag strap studs).
If either of these are slightly bent they can pull the crankcases out of correct alignment (radially), misaligning one half of the crankcase with the other, and creating an uneven barrel base surface that has more potential to leak...Ian
The reason that they may be coming loose is the sheer weight of the barrel and head, I notice that when I rebuild a lot of engines with heavy cylinders that the gasketrs settle down for a good while after initial installation and tightening. Some engines, I may have to tighten the base nuts with a copper hammer and just a week later they are only finger tight!