Case Torqueing
 

I'm very close to buttoning my 3.0SC case and I was wondering about the torquing procedures. I've read many articles here on case sealants,etc.

Question 1:

Torque values on wrenches greatly vary depending if the stud is dry or oiled. I think that oil is required to get a proper torque value. My question with regards to case perimeter and through bolts, does anyone oil the stud after the case halves have been put together to achieve the proper torque? I don't recall mention of this.

Question 2:

The consensus seems to be to torque the perimeter first. If I'm using threebond 1104 does this hold true? And is there any pattern to torquing as there is to the case through bolts? I would have thought to snug up the perimeters first, then snug the case through bolts. Then torque the perimeter followed by through-bolts. Does this sound reasonable?

Question 3:

Oiling the o-rings. I plan on applying oil to the case through bolt o-rings - a simple 30W would be fine? Also, does anyone apply oil to the large oil pump o-rings. I read in Wayne's book not to do because the oil may seep onto the case mating halves.

Follow Wayne's book and you can't go wrong.

here's an old saying I try to follow...

"Beware the man that reads but one book"

The answers I'm looking for, as far as I can tell, are not in Wayne's book.

My opinion:
1. No oil on regular case perimeter bolts. Locktite 270 on all non oiled bolts.
2. Oil on case through bolts.
3. Dow corning 111 on the O-rings.

Kirk

Well I wouldn't say you can't go wrong. Case through bolts go opposite of Wanye's book and silicone on the case washers is an amateur mistake.
We don't do it and never would.

I've seen a couple of Tom Woodford's engine jobs and he's a fan of putting silicone on the washers but I have never seen a top flight mechanic use this technique.

If the case sealing area shows signs of distortion we machine the surface for proper sealing.

We use Dow 55 oring lube on the orings, Wurth copper anti seize on the threads of the case through bolts. The 8mm perimeter nuts are installed dry.

With TreeBond sealant you snug the perimeter nuts, torque the case through bolts and then torque the perimeter nuts.

Well, OK Henry - I guess you got me there. I did follow the book on my 2.2 rebuild and came away with a leak free motor. I didn't use the silicon in the washers as suggested, it didn't sound right to me either.

A leak free mag engine. No leaks!!! Knock on wood....

Good for you.