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Sat Nov 07, 2009 1:25 pm

I recently started an engine rebuild on my '71 bus. Never done this before, and I've hit my first snag.

I'm trying to remove the cylinder heads, but some of the studs that go into the case are turning instead of the nuts. I haven't pulled the studs all the way out yet, as I thought it best to get advice before I go too much further.

In searching the forums, I've heard of "case savers". Are these the correct way to deal with this? If so, do I remove the heads studs entirely and bring the case into a machine shop?

Thanks!

Sat Nov 07, 2009 1:40 pm

you splitting the case for this rebuild? taking P&Cs off?

its ok if the studs come out. if going full rebuild, take em all out.

check that one after removing P&Cs to see if it is too loose or wobbly. if so, case saver might be in order.

Sat Nov 07, 2009 1:53 pm

Its no big deal the studs screw into the case and the torque to turn the nut is greater than the torque required to unscrew the stud because the nut is corroded.

Sat Nov 07, 2009 1:57 pm

Yes--complete rebuild.
How would I torque the studs back into the case without a nut on them? Aren't they supposed to be locked in there somehow?

Sat Nov 07, 2009 2:00 pm

double nut on the end of the stud to screw em back in. nope not locked. =) screw em in just till the very last thread is gone.

Sat Nov 07, 2009 2:37 pm

Use your wire wheel if you have one and clean the threads. When you reinstall the head bolts use the red locktight you can do that anytime be sure to clean the threads in the case.

Sat Nov 07, 2009 4:37 pm

to remove the nuts just grab the studs securely with a pair of vice grips or you can let the nut pull the stud and mount the non-threaded part in a vice and unscrew the nut.

When the engine is apart carefully look at where the studs go into the case. If there are shiny things screwed into the case where the studs are, and then the studs screw into them, you already have case savers. If the studs screw directly into threads in the case you do not have case savers and it would be a wise idea to have them put in because the studs commonly strip the threads out of the engine case over time. Nothing like a pulled stud a month after rebuilding an engine so do it now while it is apart.

When you put the studs back in, use locktite or some of the white Napa thread sealant to prevent leaks. You can screw the studs back in with two nuts locked on the end to turn it. I like to wire brush the studs and threads while they are out.

Sat Nov 07, 2009 10:35 pm

You would be much better off reviewing what Tom Wilson say's about it. You really need his info anyway for the work you are doing. There are other things involved. Do you have 10mm studs or the 8mm? If 10mm they probably don't have case savers unless they were later added. With an old case you really should have case savers. If not, it would be real good to take it to an experienced VW machine shop and have them installed. And deep stud in the one touchy one at #3. An original '71 (AE case) probably has the 10mm studs. Later cases use 8mm with the case savers. My bug has 10mm (with case savers) and the bus has 8mm with case savers. The later engines have 8mm and case savers. I so much more prefer the 8mm. 10mm are too strong and when the engine heats and expands they hold the engine together with brute force and are more apt to pull from the case. 8mm's stretch with the engine expansion and are more consistant with the clamping force. Basicly the torque is consistant. with 10mms it isn't. Which ever ones you have torque them correctly. Different torques.
A couple of the studs on #2 can seep oil since their holes go all the way thru the case. Be sure and use sealant on them. I use Permatex Aviation and use it on all the studs also. When unscrewing the nuts it's good to hold them with vice grips so the studs don't turn out. If studs turn out of case savers that's one thing but if there were casesavers that turn out with the studs that's not the greatest. Casesavers should be good and tight.
Again, please get the Wilson book if you don't already have it. "How to Rebuild Your AirCooled VW Engine".

Sat Nov 07, 2009 11:09 pm

both my original and later a replacement 1971 AE case came without case savers. I remember because I a stud came loose and I had to put casesavers in to fix it. My lady friend at the time took me to work all that week while I was rebuilding the engine - and I do remember her quite well too. She had one of those faces and figures a guy dreams he will meet once in his life....... and a temper to match, part Yaqui Native American.

Sun Nov 08, 2009 6:27 am

No, it doesn't have case savers. Yep, I've got the Wilson and Muir books, but both are very vague about this subject. The guy in the Bug Me video says case savers started being installed at the factory around '73.

Good thinking about holding the stuff with vice grips.... should have thought of this at the time. But considering the amount of torque I had to put on the nuts, they probably would just have slid anyway.

Thanks!