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Posted by: dcecc1968 Nov 19 2019, 08:52 AM

Can't seem to find a reference for the size of this bit. Thanks for your help.
-Don

Posted by: jcd914 Nov 19 2019, 09:11 AM

This is from a VW TDI forum page:

"The triple square, also known as XZN, is a type of screw drive with 12 equally spaced tips, each with a 90 degree angle. Its name derives from overlaying 3 equal squares to form such a pattern with 12 right-angled tips. Common sizes are 6, 8, 10, and 12 mm"

I believe the 914 CVs use the 8mm size bit.

Jim

Posted by: mepstein Nov 19 2019, 09:16 AM

My local FLAPS had 4 different size bits for about $8

Posted by: injunmort Nov 19 2019, 09:18 AM

triple square size 8

Posted by: wndsrfr Nov 19 2019, 09:51 AM

IMO replace them with 6point allen head and cross drill the heads for safety wire. Somebody here sells them...

Posted by: Chi-town Nov 19 2019, 10:24 AM

Or cross drill the stock bolts and get the same security and save money?

I'll never understand why everyone swaps out for allen head bolts

Posted by: dcecc1968 Nov 19 2019, 10:30 AM

Appreciate it fellas!

Posted by: jcd914 Nov 19 2019, 10:36 AM

IMO using 6 point Allen bolts is a mistake. In my experience the allen heads strip much easier than the 12 point triple square bolts. The triple square drive was designed to handle more torque than the older design of the allen heads.

The key to being successful with either style bolt is cleaning the heads of the bolts out so the tool fits all the way in so you have full engagement. Also make sure the threads on the bolt and in the bolt hole are clean when you assemble them. And use a torque wrench to get the correct torque on them.

The safety wire is a very good idea but kind of a PITA to wire them.

Jim

Posted by: Olympic 914 Nov 19 2019, 12:30 PM

I have found that after cleaning with a screwdriver or other pointed object, place the tool in and give it a few taps with a small hammer to seat the tool before trying to remove them.

Posted by: bdstone914 Nov 19 2019, 12:37 PM

Posted by: rick 918-S Nov 19 2019, 12:37 PM

and replace the schnor washers. Proper torque is a must. Triple square bolts are harder to strip if the female is clean the the male can fully engage

Posted by: ClayPerrine Nov 19 2019, 12:50 PM

If you follow the factory procedure to replace the schnorr washers EVERY TIME you remove the bolts, and properly torque them, you will never have an issue with them backing out. The safety wire is a fix for the problem of "not following the directions".

Posted by: cuddy_k Nov 19 2019, 03:04 PM

Usually the dirtier the female, the easier for the male to engage, but that doesn't apply to cars

Since this comes up every so often...

M8 Triple square:

https://www.amazon.com/Capri-Tools-30034-Triple-Square/dp/B00ESMZYV6/ref=sr_1_6?crid=B3QOTFA5I44T&keywords=m8+triple+square+bit&qid=1574197290&sprefix=M8+triple+%2Caps%2C125&sr=8-6

Schnoor washers:

https://www.belmetric.com/steel-c-4_39_1020/wsh8blk-schnorr-washer-black-p-11238.html?zenid=j1tkl4ee2l4papv7dfk9do7kh7

Posted by: dcecc1968 Nov 19 2019, 09:12 PM

Great advice as always fellas!

Posted by: Rob-O Nov 19 2019, 10:15 PM

Id also add that from my experience most people don’t know what they’re doing when safety wiring.

I have a bag of 100 Schnorr washers. Send me a PM and I’ll throw some in an envelope for you. The ridges of the Schnorr washers lock the bolt in place. But you crush those ridges in the process of torquing the bolt. So, it’s a one time use only washer. Since people don’t follow the directions and change them after each use, they get to a point when the washer won’t hold the bolt and it keeps backing out. So they spend time and money on the safety wire solution. Safety wire isn’t meant to keep the bolt torqued, it’s there to stop a catastrophic failure if the bolt does come loose.

Posted by: Tdskip Nov 20 2019, 10:56 AM

As others have suggested you REALLY need to make sure the head is totally snug in the CV bolt, I always tap it fully seated to avoid stripping them.

Posted by: Mikey914 Nov 20 2019, 11:12 AM

Or start by hand and get 3-4 turns in before going to the wrench.
Yes most folks aren't really good at safety wire, but it will keep the bolt from backing out.

You also do not need to do every bolt you can do every other.

Posted by: Rob-O Nov 20 2019, 12:32 PM

Assuming the safety wiring is done correctly. I’d say it’s 50% of the pictures I see if a safety wire job where the wire is done incorrectly, which would allow the bolt to loosen even with the safety wire.

Posted by: Valy Nov 21 2019, 01:23 AM

Allen bolts are a mistake.
Use the original bolts, new washer and make sure the surface of the bolts, CV and drive flange are clean and DRY of any oil or grease. Also make sure there is no RTV there as some like to use it there.

The reason those bolts back up is that dirt and grease captured on above mentioned surfaces create temporary pressure that makes you think the bolt is fully torqued. Then the dirt gives up and the bolt torque goes out the window and even the washer doesn't help anymore.