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Tue Jun 24, 2014 2:53 pm

I was sealing up some leaky tubes and cylinders on my AK 1600 and I snapped a stud the because my torque wrench didn't click. bummed me out bc it was the last torque turn on the last nut. whole head has to get re torqued. I figured I'd swap out a stud from my 1500 sitting in the shed. No dice because of the different diameter studs. 1500 head stud is much thicker. Anyone know off hand what size stud I need to order? Its a stud on the top half of the head.

Tue Jun 24, 2014 7:58 pm

The threads are the same but the expansion won't be so your head might warp if you mix 8mm and 10mm studs. Take the old one out and take it to your local VW shop; he'll have a pile of used ones. If you don't already have case-savers this is a good time to have the case drilled and tapped for them.

Or you could cheap out and only install a case-saver on the one you must change. 8mm studs are better. Just buy a set if you don't want to be taking it apart again.

You really over-torqued it to snap it. 24 ft-lbs is all you need. It takes 80 to snap a good stud and you're more likely to rip it out of the case than snap it.

Tue Jun 24, 2014 9:04 pm

Oops.

8mm X 1.25 pitch is the thinner one.

10mm X 1.5 pitch is the thicker one.

Tue Jun 24, 2014 10:37 pm

I read his post as he broke a 8mm one on a 1600 since he said the 1500 was thicker but I could be wrong

just take the broken pieces to a vw aircooled store/shop and they can get you the right one

Wed Jun 25, 2014 12:12 pm

If your vise grip spins on the broken stud, file or grind two flat spots on it to help with the grip. If the new stud is at all loose fitting, install a case saver insert. Avoid heating the case if at all possible - if you absolutely must, loosen the case bolts first to avoid warping.

Thu Jun 26, 2014 12:57 pm

I just got a bad feeling. I looked at the case and noticed all the studs have case savers. Then I looked at the case hole for the stud in question and noticed the case saver isn't there...or so it seems. Upon further inspection, the 8 mm stud still screws into the case hole, BUT the hole is a much larger diameter which means there's a case saver embedded deep into the case. My gut tells me this is bad. Soooo... Do I try and install a case saver in the larger diameter case hole, OR do I thread a new 8mm stud into the existing embedded case saver and hope for the best?

Thu Jun 26, 2014 12:59 pm

just to clarify...the broken stud is not in the case hole. It broke at the nut end so I was able to completely remove the stud from the case.

Thu Jun 26, 2014 1:09 pm

please take some clear pics of this so we can see what's going on here

Thu Jun 26, 2014 1:27 pm

@joe56. Sorry no pictures because Im not near my engine. The case hole for the stud looks like its for a 10mm stud. I have an 8mm stud. I stick it in the hole and turn and it threads as if it were an 8mm male/female connection. This made me think that a case saver was embedded and recessed in the case because I noticed all the other case studs had case savers.

Now I just did a little research and found a samba thread stating that its normal to see a stud recessed at the #3 upper cylinder without a case saver. So maybe all is ok. So I think I just need to replace the broken 8mm stud with a new 8mm stud. I'll post the verdict.

Thu Jun 26, 2014 1:59 pm

Case manufacturers recess the case saver at that one location because it is the one that habitually failed. Get a flashlight and a bicycle spoke to probe deep in the hole and you will probably find it has one.

Thu Jun 26, 2014 3:23 pm

S0-while the stud is out-spray some wd-40 down the recess and blow compressed air on top(to pressurize the deep hole). Observe the front mount flange and look for the wd-40 to leak out in front of the flywheel. --You can also spray soap like windex across the face of the block and look for bubbles.

It was common for that deep case saver to cause cracks to the oil galley there and spray oil on the back of the flywheel.

Mon Jun 30, 2014 8:49 am

replaced the stud. case saver was recessed. didn't have to remove the head. lock washer between 2 nuts allowed me to thread/tighten the stud in the case. engine is back in the bus.