where can i get copper head gaskets. and does anyone carry heavier duty head bolts and studs thyan the crap that comes on these grubees....
I feel that M6x1.0 should be torqued to 6 to 8 foot pounds (72-96 inch pounds), and the M8x1.25 should be a MAXIMUM of 204 (17 foot pounds) INCH pounds. I use 50 and 150 respectfully. I upgrade all studs and only use lock nuts. With these specs I have NEVER blown out a head gasket. I mill (sand) the cylinder and head, also use copper cote sealer, permatex 80697 will do the same job. I also have a inch torque wrench, which will give a much more accurate results.Use something like Permatex Copper Hi-Temp Spray-a-Gasket and a torque wrench. You might also need to tap the head stud holes, too. The Chinese have a tendency to not fully tap the holes. That goes for the mounting and intake and exhaust studs too. That has been the problem with many heads that haven't sealed right. The stud bottoms out too soon and the the acorn nut gets to the bottom of it's thread and you get false torque readings. M6 1.00 torque to 10 lbs and an M8 1.00 or 1.25 to 15lbs. Use some kind of a torque pattern like an "X" or "Z" , don't just go in a circle around the head. That causes an uneven force on the head and can lead to failure.
i had that problem with the acorn nut bottoming out against the dome, so I simply Dremeled off the dome portion of the nut, and everything has been fine ever since.Dave C is correct about the acorn nuts bottoming. I've seen too many for it to be a random issue. Replace them with shouldered hex nuts. Proper torque and a flat sealing surface is essential for a good head gasket seal. Good luck.
Tom
If that was the case, then there would be no issue of false torque reading due to the stud bottoming out in the dome.Usually when you 'bottom out' those cheap acorn nuts, the dome will just pop off.