CV Joint Bolt Torque Specs?

ztnoo · Post by **ztnoo** » Mon Mar 28, 2005 6:44 am

I'm reassembling the left rear of the '74 I'm working on (see "Three Things In Hoosierland" thread).
I need to know the torque specs on those bolts. I've looked through all my literature, but can't locate a spec.
This is a high load/ high stress area and even the novice mechanic in me knows this is an extremely important detail.
Anyone have a torque spec on this part...12 point, 8 x 48 mm, "cheese head " bolt, part # 113 501 229?

ztnoo · Post by **ztnoo** » Mon Mar 28, 2005 5:44 pm

Gentlemen,
I have two bids at 25 ft/lbs. and one at 30-33 ft/lbs.
Do I hear another bid? going, going ....gone.
I think I'm in the ball park at the higher end.
Gonna go with 30 ft/lbs. .....unless otherwise directed.
Thanks guys.......
Regards

Post by **Marc** » Mon Mar 28, 2005 5:53 pm

I don't have a spec for a Thing, but for a Type IV which uses the same CVs it's 32 and for Type I, II, and III it's 25lb-ft.
30 sounds fine.

ztnoo · Post by **ztnoo** » Mon Mar 28, 2005 6:03 pm

Marc,
Thanks for your vote of confidence.

ztnoo · Post by **ztnoo** » Wed Mar 30, 2005 3:05 am

Thought I'd relate a bit of information I discovered about the CV bolts and the tools used to remove/replace them.
If you are aware of this, please excuse my inexperience and naivety.
It seems the major American automotive tool manufacturers (Snap-On, Matco, Cornwell, etc.) refer to these driver bit/sockets as "Triple Square" bit sockets.
Makes sense...do the math.
But if you are looking for a "12 point" bit socket for these specialty bolts to match an exist set of tools, or attempting to buy a single item through a local automotive parts supply store or shop/garage, you'll likely have more success using the terminology these manufacturers seem to prefer.

ztnoo · Post by **ztnoo** » Wed Mar 30, 2005 7:15 pm

Gentleman,
Since I seem to be having a conversation with myself with very few exceptions, I might as well continue.
Today after finishing the left rear cv/halfshaft redo on the '74 because of a broken cv bolt, I thought to myself...I wonder if the right side is ok.
Since the entire rear end was jacked up, it just made sense to check the torque spec on that side.
The third bolt I tried was broken, on the outer cv, just like the left side. It wasn't protruding from the cv like the left side was, therefore it was unnoticeable, until you put a "triple square" socket bit on it. Voila! Duh. Guess I should have suspected I might find the same situation.

Guys what I'm trying to say simplistically here is, if you haven't been under the posterior, rearward end of your Thing lately to look around and check things out, you might want to look at it in your shop/garage.....otherwise you'll eventually be looking at it on the road...or in the boondocks somewhere, immobilized. Somewhere where repair will be difficult at best, if not impossible.
I would say the longer one has set without use and attentive maintenance, the greater the likelihood of problems.
A word to the wise.....jack it up and crawl under it and check those cv joint bolts out, before they check you out.
I have two more Things to check out, and I'm betting I'll find the same problem on both of them.

Research notes on cv bolts:

From Bently: Official Service Manual-----S. Beetle, Beetle, & Karmann-Ghia, 1970-1979
Transmission and Rear Axle; p. 5; 3.1 Removing and Installing Driveshafts
"Caution---do not remove twelve-point driveshaft screws, if installed, with a hex-key as it may damage the screws. Use a twelve point driver."

From Haynes: VW Beetle & Karmann-Ghia-----1954-1970
Chapter 8 Clutch and driveline; page 8-14; #11 Driveaxles-removal and installation
"Caution---Earlier models use Allen bolts; later models use spline-drive bolts. Don't try to loosen Allen bolts with spline-drive bits, or vice-versa.
You'll strip out the recessed centers of the bolts making removal much more difficult.

No matter what you have done or have gotten away with in the past...you maybe be asking for trouble whether you are a new owner/mechanical dork, or an experienced wrench.

I'm going with the 12 point, "triple square" option.
I've got enough other things to attend to and get right without screwing up cv joints and bolts....something that's critically and vitally important.

ztnoo · Post by **ztnoo** » Thu Mar 31, 2005 7:06 pm

"Personally I would go for the 33 foot pound spec. I have had those damn drive lines fall off on a few occasions. I didn?t break any bolts; they just worked themselves loose and slipped off. You would step on the gas and the engine would rev up but there was no forward motion just a slight grinding noise of the axle shaft rubbing on the frame horn. After I started cranking the bolts to 35 foot pounds I didn?t have the problem anymore.

I think it would be prudent (in my case) to drill the bolt heads and also run a safety wire to keep them where they belong."

suntour http://www.thesamba.com/vw/forum/viewtopic.php?t=108234

Suntour,
Hey that's not a bad idea at all ...the safety wire idea.
The owner of two of the Things I'm working on and I road raced Yamaha 250's back in the early '70's.
All the critical and important bolts and nuts of those rockets of the time, were safety wired.
The locking, spin pliers (the correct description escapes me, an aviation mechanical tool) were all that was required, and that tool was part and parcel of every two wheeled road racer's tool box...

If someone is having a continuing problem or absolutely wants to prevent these bolts from backing out....drill the suckers out and wire them.
The only thing you won't know without cutting the wire and torquing, is if they are broken.
They can be as deceiving looking safety wired, as they are unwired.
Broken is broken, whether it is wired or unwired.

Thanks for your torque spec input.

http://www.thesamba.com/vw/forum/viewtopic.php?t=108234

radioman · Post by **radioman** » Tue Apr 05, 2005 3:54 pm

ztnoo: I got my "triple square 8 mm" doohickey today and checked my CV bolts. All tight and in spec!!!!Thanks for your post...it made me address something I had overlooked.