Head Bolt Torque Setting
06-21-2003, 11:56 AM
#16
Rennlist Member
I looked it up in the introduction literature for the 964 and the silicon cylinder BASE sealing "O" rings are described as being part of the original 1989 964 specification, so I am sure they are on the 1990. They are also shown in the parts fiche for the 1990 car.
The cylinder TOP sealing ring was added in 1991 when cylinder head to cylinder seal failures occurred with the original non-gasketed tapered cylinder design. The cylinder studs were changed at that time to steel from the original Dilavar but the torque spec remained the same. <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />
The cylinder TOP sealing ring was added in 1991 when cylinder head to cylinder seal failures occurred with the original non-gasketed tapered cylinder design. The cylinder studs were changed at that time to steel from the original Dilavar but the torque spec remained the same. <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />
06-21-2003, 01:45 PM
#17
Cylinder base to block o-ring, part number
999 707 152 40 was from first production of 964 engine.
Cylinder to head seal, part number
964 104 115 20, was from specific engine number of 91 model year.
999 707 152 40 was from first production of 964 engine.
Cylinder to head seal, part number
964 104 115 20, was from specific engine number of 91 model year.
