Should have replaced two of my bolts that hold the half-shaft to the tranny hub last time when I saw the 12 points failing.....but I didn't.

Now I've got 2 that I cannot get out and they are totally stripped in the 12-pt. center.

Have good bolt remover but it won't get on the head because distance to center is too small.

My small 10" pipe wrench can't get a grip on it either.

Should I heat where threads are on hub?

Any suggestions are greatly appreciated. Tranny ready to come off except for these two bolts.

TIA,

GN

Pics coming shortly....

Big vice grips and heat?

lots of kroil

Yes, had 12-pt bit under great pressure before rotating......bit is good, no wear on it....





10" pipe wrench too big to fit on head...

Air hammer/chisel. Makes short work of it.

Use the air hammer chisel on the edge of the bolt to spin it out as @mepstein says. If no air hammer use a sharp chisel and hammer to do the same. Worst case take your die grinder with a good cutting wheel and cut it off.

He hit all the things I'd try.

I've found the "trick" with 12 points (triple square for some-especially when looking for tools) is to CLEAN them out completely. Pick and air first then pick and carb cleaner then air. Medically clean before any torque is applied.

Works much better when stupid clean (this is before the centers are FUBAR).

Another thing that might help right now.
Cut the rubber boot off and clean up all of the grease before going much further.
Improve access to your playing field...
Boots look old anyway.

Lucky that wasn't at the trailing arm side!

I've had good luck with a very good pair of vice-grips. A cheap pair doesn't usually grip well enough.

Never tried the air-chisel.

Cleaning them and using a good tool is the first step.

Try a Knipex Cobra - they make them down to 100mm, but longer will give more leverage.

https://www.knipex.com/products/pipe-wrench...ter-pump-pliers

I would use a whiz wheel to cut a slot in the head then use a impact driver with a straight bit, smack it good. I've had to do this several times myself ,never failed to get them out.

Todd

This gets my vote if you can't get a pair of vice grips on it.
If you don't have air tools, you could use a dremel to cut a big enough slot in the head to fit a big ass flathead screw driver in it sideways and loosen it. You wouldn't have to cut the boot that way.
Click to view attachment

Don't have any tips to help; just a question:

Why does the 914 use 12 point socket head screws whereas my '86 911 uses 6 point (hex) socket head screws? Seems like the 6 point has more material to bite on.

I read a note on the PMB site that they replace the 12 pt with 6 pt when they leave the shop.

There's nothing wrong with 12-point socket heads...when used correctly. VW used them throughout the Rabbit/Scirocco line, too.

- Clean the threads
- Rotate the shaft so your tools/extensions inline with the axis of the bolt
- 31 ft-lbs. No more, no less
- Use these: https://914rubber.com/cv-joint-bolt-m8-x-45-1-1
- And these: https://914rubber.com/schnorr-washer-for-8mm
- Safety wire them
- Keep a couple extra around to replace them if one gets buggered up

I've never had a problem with these bolts, in any of my VW or Porsche. - GA

Definitely clean any 12 point with a pic and brake cleaner. Every time

I don’t have trouble with 12 point either

Many thanks to all for all the great ideas.

My thought was that an 8" pipe wrench should fit the head and the clearances. Found a nice one at my local hardware store just 4 country hiway miles away, $15 and worth every penny - and the bolts came off incredibly easy.

I was planning on Dremel the heads off if the 8" didn't work.

Great thing about a pipe wrench vs. vise grips is that the more torque you put on the wrench, the tighter it grips. Could not believe how easy they both came out. As always, having the right tool for the job is everything.

And great tips/wisdom about thoroughly cleaning both the 12 pt. bit and the bolts before torquing. I've never used them before in almost 60 years of wrenching. I can see cleaning them as being the critical issue.

Also great point in how critical correct torque is.

Again, thanks for all the great ideas.

GN

Wrench below:

You will try lots of things to get this bad boy off but I am thinking that you clean the hell out of it and then squeeze a hard nut on it with a vice grip and weld it on. Remove the grips and The heat from welding should help and you should be able to get it off.

You know that you are going to dick with a number of different ways and then the satisfying sound of the nut coming loose.

Good luck,

Bob B

Bob -

Thanks! But guessed you missed the part that I got it off quite easily with a smal 8" pipe wrench.

I didn't think anyone made them that small, but found one right away - perfect tool for the job - and any like it in the future. A tool I'm really glad to have now.

GN

MORE TOOLS!

When I had this issue I welded some steel to the end of the stripped bolt and turned it out. Took longer to set up the welder then to free the stripped bolts.

I’ve replaced them all with Allen socket bolts.

Zach

If you try the welder be sure to ground directly to the head of the bolt. Otherwise you risk arching all the bearing right thru the grease in the whole car. I had a welding instructor that started out working is the mines. He was told to repair a conveyor. Connected the ground at one end and welded on the other end. Arched all the bearing in the conveyor.

Zach -

I'd do the same but just ordered some new 12pt ones from AA.......

Next time for sure.......

Where did you find hardened ones? Do they need to be Grade 3 or 5?

GN

One cannot have too many tools......!

And there is nothing like that wonderful feeling when you need a rare and special tool and have one tucked away!

I think the only addiction I have is a Tool Addiction. A woman has to buy new shoes or clothes. Me? If I'm down, I just go buy a tool I don't have and all is well.

GN

Don't mean to be patting myself on the back - but it does seem to me that the 8" pipe wrench is the most simple and easy means of removal of a stripped 12pt 8x45 bolt on the hub. Easy and only takes a few seconds.

Hope others can use it in the future.

GN

Baby pipe wrench!

I have tons of tool and I don't have that.

Yet...

Good find, a tiny little pipe wrench is a good idea!

I do have a pair of channel locks that are about 3" long.

Pretty useless until they are PRICELESS!

I've used them 3, maybe 4 times in my life...

@'Gatornapper'

I miss a lot of stuff these days. This is a very small light weight wrench that I embedded in plastic back in 1977. We did 500 of these for Proto Tools and they gave them away.

Best Bob B
Click to view attachment

That would be a REAL bitch...

You have the tool, but it's encased in plastic!

Nice looking tiny pipe wrench...

12 point triple square and Torx can handle more torque than 6 point allen. As stated by others the problem is when the wrong tool is used (allen wrench instead of a triple square tool) or when the fastener head is filled with debris and the tool isn’t seating inside the head to full depth.

It’s all about the angle at which the tool tries to drive the fastener. The closer the tool contact is to 90 degrees - the better.

Hopefully these illustrations help explain

Click to view attachment
https://en.m.wikipedia.org/wiki/Torx#:~:tex...%20Torx%20drive.


Click to view attachment

@spoke

SuperHawk is right!

In use and repair I have found more failures with 12 point than 6...

Now the REAL questions

WTF (why the fwck) do they call that triple square instead of 12 point?

I couldn't find shit when I looked up 12 point.

Replace it with triple square and I found a completely usable set of 9 in stock at AutoZone for less than I was willing to pay for a single!

I've got 12 point Allens that I will NEVER use now...

Study the bottom image (previous post above)

A triple square is as the name implies. It’s an overlay of three; four point squares. Each with 90 degree corners

A 12 point bolt head (or 12 point double hex would be the overlay of two hex shapes with 120 degrees between faces)

Double hex below:

Click to view attachment

Thus, the 90 degree corners...

Robertson is a single square. Those of you with enclosed trailers are well-versed in double square screws (and you probably use a Robertson bit from Lowe's on them).

VAG and Porsche use triple squares in a lot of places (even today). It's a good fastener that, when used properly, will grip tight and not cam out.

In cases like these, I’ve always found the 12 point triple squares already compromised by previous well meaning folks that don’t have the proper tools.

There are so many fasteners variations, you have to know what you have.

Sort of like JIS fasteners on Japanese motorcycles that are always buggered by someone trying to use a Phillips on it. Works about 60% of the time but more often than not leaves the fastener compromised for the next guy.

Don’t even get me started on Whitworth on Britt bikes

Save it for Toyota’s or other Asian vehicles. I’ve seen double hex used on those occasionally.

I have a 1950s vintage South Bend Mill that has double hex on the fasteners that tighten the head to the ram. Not sure if those are original or were replaced at some point. They seem original but on machinery that old - who knows for sure.

Fwcking A!
Feel like a moron!
Should have just looked a tiny bit closer at SH's post.

Bad ninja! Bad bad ninja!

Now I know why I see so many screwed up ones...

Someone tried to use an allen previously and the angles are all wrong.

That is the ticket. I use a 4" pipe wrench.

WHAT GREAT INFO!

Many thanks!

Just last year I realized I needed a small pipe wrench in my tool set, and found a nice 10" one at Lowe's. BUT it was just a bit too big to work on the 12pt bolts.

Called our great local hardware store to see if they had an 8" - "sorry, no" But then the manager called me right back, "I found one!" Immediately drove 4 miles (country - straight road, 55mph, 2 stoplights) and got it.

Amazed at how it turned a difficult task into an easy one.

I'm sticking with the 12pt ones - 4 new ones on way from AA, will clean them and the tool for sure each time now....

GN

Ok - you got me.

Now I search for 4" pipe wrench. Gotta have it.

GN

Another tool to buy.

I HATE buying new tools...

I have to find a spot for them in my boxes, I have many!

Then I FORGET where I put that little bitch and spend way too much time looking for it.

Now, when I see a tool that has value to me (like a tiny little pipe wrench) I just have to buy it...

Wait til you get to be 78. You'll forget 10x as much.

But again, as I said earlier, there are few things that make you feel better than desperately needing a rare tool - and remembering that you have one!

Keeping my eye out for a 6' pipe wrench now.....

GN

Wait, wuuuut? Why else would we want to work on cars???

Picked this one up somewhere. Not 4" looks like a 6"

Still pretty cute.

Click to view attachment

"You gone on keep telling yourself that, sweetheart."

And there you have it folks. And now he has it. Another tool for the collection