Richard S

What is the correct torque for the large plug at the end of an S4 head?



Thanks, Rich

Rob Edwards

This is going to sound like a preposterous amount of torque, but I once watched Greg torque one of these to 60 ft lbs, with Drei-Bond on the crush ring.

Richard S

Holy crap! That's a lot more than I thought. Seems like that plug/threads would deform with that much torque.

Thanks, Rich

Rob Edwards

This might be one of those times where a second opinion is a good idea, but I'm pretty sure I'm remembering the value correctly, and it's a large diameter plug with plenty of thread engagement surface. And you don't want it to leak, given that getting at it again means removing the timing belt and belt covers. I looked around a bit last night and couldn't find that torque value in any of the printed literature. Maybe it exists in the 944 or 968 WSM (?)

Schocki

There is nothing about this plug in either WSM (944 or 968). I found this general purpose torque chart online. The sealing ring used for this plug is a C 38 x 44. I assume, that we are dealing with a standard M 38 x 1,5 metric thread. 60 NM with some sealant around the sealing ring will be enough (even less would be OK IMHO). If you compare this to the oil drain plug with a M 20 x 1,5 thread and 50 NM in aluminium, 60 NM is just fine.

Richard S

60 Nm is about 44 ft-lbs, so seems a bit more reasonable.

Thanks!
Rich

Rob Edwards

To be honest I like the sound of 44 ft-lbs better too. But then I'm kind of the king of the undertorqued fasteners....

jpitman2

IIRC the pan drain plug is steel, and screws into an inserted thread (Helicoil?), not direct to alloy. Dont think its quite the same.
jp 83 Euro S AT 57k