Replacing socket head screws on the CV joint

[crvc]

Using a hand sledge and chisel is the only way I could break these loose. Can I use normal metric bolts instead of these? I'd have to over the special wrench which would take a week or more. If I use bolts, what's the torque setting?

kevin

[harryset]

We're talking drive train and safety here. So unless you find bolts with the same hardness, don't press your luck.

[Dale M.]

IF you can not get it out... Cut head off.... Remove other bolts... And then go after remaining stub (on one you cut head off) .....

"Allen Head Cap Screws" (general merchandise item - metric) are 160,000 psi High Carbon Steel, appropriate size should be ok.... Using Allen head bolt may be easier to find and use as replacement, but it is also easier to strip Allen Head than standard 12 point CV bolt head......

"Standard" CV joint bolts are available from many sources, here is just one......

http://www2.cip1.com/ProductDetails.asp ... -501-229-D

Proper tool for "standard" CV joint bolt is...

http://www2.cip1.com/ProductDetails.asp ... C-C10-7011

Torque for "standard" CV joint bolt.... 25 ft-lbs...

I personally would go to O'Rileys (old Kragen) or Auto Zone or NAPA and and get proper 8 mm 12 point socket.... Most quality auto parts stores have them on their tool wall..... They are NOT a specialty VW item, but pretty much a industry standard.......

Above mentioned auto parts may also have "CV bolt kits" available..... Do the research before you cobble something together that will cause you more grief later....

Dale

[aussiebug]

Yes - best to stick to the correct bolt. The full title for the tool used is an 8mm 12 point SPLINE DRIVE. Do NOT get a torx bit - they have a different shape to the "teeth" and might strip the bolt heads. The one advertised on the cip1 site will work OK, but if you can find one (Harbor Freight or similar maybe) with a longer shaft, you'll find it much easier to work with around the rubber boot. Mine is a 1/2" drive (not 3/8") and the shaft is about 3 inches long - works very well as I can get a ratchet drive directly on to the tool without interfering with the rubber CV boot.

Yes -the correct torque is 25 ftlbs.

Make sure you use both the "twinned" washers and the special locking washers with tiny teeth - if those bolts come loose you can end up with the end of the drive shaft thrashing around at 60mph...not pretty.

[Ol'fogasaurus]

I agree with staying with the "spline" drive head style of bolt. German engineers do not do or use something unless there is a very good reason for it (believe me; I have worked enough with German engineers to understand this).

If, as suggested, you knock the head off this bolt, then remove the rest of the bolts you should be able to slide the CV off the remaining bolt shank. It should be east to remove the remaining bolt shank after that.

The torque readings in the books say either 25# or 32# of torque (depending on which book you look in). After having one set of bolts back out (not uncommon) after a 25# torque, I was told to go to the 32# torque setting, then double check it for a while (I also used a dab of Locktite [reg] but not everyone recommends that). Since then I have not had a problem nor have I been stranded out on the sand with a drive axle dangling down.

There is a special set of washer designed for Allen Head/"spline" drive (small head fasteners) fasteners, if you can locate a set, that fit snugly under the head of Allen bolts. A lot of off-roaders use these if they don't use the load bearing/distributing strap that your pictures show that you still have. The washers come in a bag of 100 and are a little expensive (reminder to me: I need to get a bag of them. I split a bag with a friend but I am working on another project that needs new bolts and I need to know where he got them ).

I hope this helps.

Lee

Edited once to clarify a torque reading and change the type of head (over the years I got too use to refering the small head bolts as Allen Head fasteners. We were not allowed to use "spline" head fasteners. I don't know if this is their real name but it sounds good to me) of the fastener used. Lee

[Dale M.]

YES!... 8mm 12 point SPLINE DRIVE... Always seemed odd to me to call the tool a "socket", but did not have a better description for it......

Dale

[Turbinepowered]

If I'm not mistaken, they're also referred to as "XZN" fasteners.

Advance, O'Reilly's, NAPA should all be able to get them for you, if they don't already have a three pack (8,10,12mm) on the shelf.

[Dale M.]

If I'm not mistaken, they're also referred to as "XZN" fasteners.

Advance, O'Reilly's, NAPA should all be able to get them for you, if they don't already have a three pack (8,10,12mm) on the shelf.

Think you nailed it...........

http://en.wikipedia.org/wiki/Triple_square

Dale

[Lotrat]

The tool and replacement hardware can be picked up at any VW parts store that sells Empi...

$6 bucks for the tool: 5796
$1 buck for each bolt: 87-7701
$5 bucks for a set of six: 16-2409

[hemicat]

I dont know if anyone has really answered your question about using a regular hex head fastener but im going to have to bust your bubble. They will not work because the head is too big. Well the head will fit but the socket will not. Been there tried that. I was able to use a pair of locking pliers and get mine out. Another trick you might try is taking youe hammer and getting a punch (pref the size of the head or a littlr bit bigger) and smacking the head a good time or two. Usually works well by relieving just enough stress from the bolt allowing you to be able to break it loose. Or sometimes just break it, but by that time its already done for. As for using loctite its not a bad idea. It works better imo than washers because it fills the void and doesnt allow vibration to affect it as bad. But for added insurance washer and loctite wont hurt.

[crvc]

Thanks for the info. I called the only places open on Sunday and they didn't know what "XZN" fasteners were. Hopefully today I'll find some. If not, I'll order a new set of bolts and driver.

kevin

[Bruce2]

The tool and replacement hardware can be picked up at any VW parts store that sells Empi...

$6 bucks for the tool: 5796

I would stay away from such a piece of junk. If the OP buys that tool, his next topic will be trying to get the busted tip out of the head of the screw.

I bought my 3/8" drive bit from the Snap-On guy about 20 years ago. Still working on the first tip.

[Ol'fogasaurus]

Well, I am really amazed! After 34 years of working with fasteners and stuff, I had never heard of a fastener code for a bolt other than a hi-lock style fastener and its collar. Rivet codes, yes and I think there was one other permanently applied style of fastener (Cinch bolt?) of bolt but nothing else that I knew of was coded that way. It is amazing what one can learn where you least expect it. I was doing a one sided PM with/to Dale M and I told him that I was aware of XTN as a rivet code but later remembered it was an XZN that was one of the codes for a rivet (I’ve been off the board and retired too long and “Old-timers’ disease” is setting in hard and fast). A big thanks from me to Dale M for finding the fastener topic on Wikipedia.

It doesn’t surprise me that, unless they sold fasteners to Aerospace or to the Government (I am not sure about the auto industry since I never worked there), that a nut and bolt store would know a bolt by either the fastener code or a part number that was out of the Standards books. We have some around here that surpirse you and do know this stuff but then there is a lot of Aerospace and Gov work around here too but most of them, when you ask for a specific bolt by name.number, well, their eyes just gloss over.

Standard hex head style of bolts theoretically could be installed but you would have to use a Crows Foot attachment to your torque wrench to torque them in. I think that they would not be a good choice of fastener though mainly because of the potential of its head being too close to the CV boot (riding the radius of the boot’s plate and the boot itself) and (potentially) could wearing/worrying a spot though the boot. On high travel/angle suspensions, I have occasionally seen signs on the boot of the cap screws coming into contact with it.

As far as a Snapon tool being the best, it may be but I have used an EMPI socket tool for almost 20 years and it is still in pretty good shape. Granted, I don’t use it all the time and; granted, I am very careful when using it so that probably does make a difference. I also clean the cap out before I try to work with the fastener too making sure that the tool bottoms out before I put a load on it.

Anyway, thanks CRVC for the topic. Good post.

Lee

[crvc]

Yeah, don't mention it. After several quizzical stares at various parts stores I gave up looking for the 12-point tool and fasterners. So they're on their way from CIP1.

kevin

[Dale M.]

For the tool I walked into local KRAGEN ( now O'Reilly) and it was just hanging there on tool wall...

Most of the time any more you have to be smarter then the parts clerk.... A lot of them were not smart enough to get job flipping burgers a local BK so now they sell auto parts.....

Dale