snapped all strut mount bolts- mystery

[Mark(The Miser)UK]

Interesting...
So the bolts weren't the problem that you thought was there with  the strut hanging low, as the bolts were broke by you in serching for the problem.

I always thought the problem you describe is down to the top strut mounting/bearing wearing out in any event; at least that is the case on a Quantum.

All bolts broke in roughly the same place, even thoughr there are 2 styles of bolt. No nuts moved along the bolt, yet even in boat anchors, nuts usually shift off the protected thread part at least partly.

Possible Causes
I think you may have forgotten which way the nut undoes and actually tightened them off. You wouldn't be the first

Did someone put 'nut lock' on the threads?

Did you use air tool to remove them? If so that could make it easier to get the direction wrong...

[92EcoDiesel Jetta]

cant help on the PN right now, but ONLY use the proper bolt. I use an airgun to install and remove those bolts and have been doing it for 16 years. I have NEVER seen what you have happen with an OEM bolt in that particular location on that particular model. The upper bolts you had were junk. the smaller shank bolt isnt really all that much smaller, but it does help. If the car is bent or other major problem, the OEM camber bolt will not compensate enough.

Are VW dealer bolts the only proper bolts? How about these from GermanAutoParts?

http://www.germanautoparts.com/Volkswagen/Jetta/Suspension/308/2

You say the upper bolts were junk. Note that the bottom bolts with a full shank also snappedd in exactly the same manner. Same junk?

If you can get me the VW parts numbers for the top and bottom bolts (and nuts since I'd need them) that'd be great.

[92EcoDiesel Jetta]

Mark,

The nuts were turned in the correct direction to loosen- 100% certain! 

It is possible there is thread lock but do you think thread lock is stronger than steel of a M12 bolt?

No air wrench. I was using a 1/2 drive ratchet with a 16" pipe for extra leverage.

[R.O.R-2.0]

Mark,

The nuts were turned in the correct direction to loosen- 100% certain! 

It is possible there is thread lock but do you think thread lock is stronger than steel of a M12 bolt?

No air wrench. I was using a 1/2 drive ratchet with a 16" pipe for extra leverage.

rattle gun would have probably broken them loose.. its the big ratchet, with the long lever on it that made them break..

impact torque breaks the rust loose, just straight, twisting torque wont loosen much rust..

[vanagonturbo]

lower bolt- N 019 551 2
upper bolt-N 101 740 02

I dont think you necessarily need to buy them from the dealer.. jsut as long as they are OEM

[92EcoDiesel Jetta]

lower bolt- N 019 551 2
upper bolt-N 101 740 02

I dont think you necessarily need to buy them from the dealer.. jsut as long as they are OEM

Thanks for the p/n's!

Is the upper bolt a camber adjusting bolt?

1stvwparts.com has them although the lower bolt is called a screw and the upper is called a bolt. Why is that? Can you double check the p/n's?

Can you get me the p/n for the nuts also? I will need 4 of those .

SCREW [Part# N0195512]
List Price:$2.90 
Your Price:$1.77 

BOLT [Part# N10174002]
List Price:$3.90 
Your Price:$2.38 

[vanagonturbo]

Well, funny thing about ze germans. Lots of times they call bolts screws. I did double check the part #s before I posted them. I can post the nuts in the morning. Keep in mind that the camber adjustment bolt is VERY similar to the other bolt. It does not have any eccentric adjustment it just has a smaller shank to allow for more movement of the spindle with respect to the strut housing. I have seen situations where two 'camber' bolts were needed on one spindle.

Its also possible that the description of the part has not been entered in congruency with what it actually is. I know the guy that runs 1stvwparts. He is a buddy of mine and he will take care of you for sure :thumbup:

[92EcoDiesel Jetta]

OK, I'd need the p/n for the smaller top nut also.

I figured out why the top hole in the knuckle was smaller than the bottom hole. Well, it was and wasn't!

After cleaning off the the broken top bolt with the smaller shank and looking at it with a magnifier, I noted that it had an eccentric shank (basically a cam) and tried to figure out how it works and saw that it could not work the way it was. Then I looked in the upper hole of the knuckle with a light and a magnifier and saw that there was an eccentric bushing inside! That was the missing part that made the eccentric shank work.

If the top bolt didn't break in half, the bushing would have been pulled out when the bolt was removed. Because the bolt broke in half, the bushing was left in the knuckle when the smaller shank pulled out, causing my confusion of the top hole being smaller than the bottom.

I ground down one of the broken 12 x 1.5 mm bolts to the shank and used that as a punch to drive the bushing out. I thought it was metal but closer inpection reveals it is plastic, probably nylon. It has a split in it and that makes sense, that's the easy way to put an eccentric bushing onto a captured eccentric shaft (captured by the bolt head and thread). Anyway I am glad I figured this out because it was driving me crazy.

[vanagonturbo]

all 4 nuts are m12. perhaps I am not making it clear enough?

[Mark(The Miser)UK]

Can you take one of the pieces of bolt with the nut on and putting in a vice, will the nuts come off? The exposed thread looks from here in pretty good condition, so it is a bit of  a mystery.

The torque required on these bolts, or at least similar ones on a' Quantum' are between 48 and 52 lb ft.  ONLY.

I have an ex brotherinlaw who would quite happily apply this kind of torque to an M6 valve cover bolt, and 100lbft + via a half inch drive socket set to an M10 lock nut.

[92EcoDiesel Jetta]

all 4 nuts are m12. perhaps I am not making it clear enough?

It's clear now! So the VW top camber adjusting bolt must be a much simpler bolt than the eccentric sleeved bolt that I broke, which looks like a much more expensive bolt. At $2 from VW, I doubt it's the same type. How does it work then? Does it have a separate washer on the nut end.

Are these bolts stretch bolts, one time use only?  

The broken top bolts are marked LE 12.9
The broken bottom bolts are marked ABC 10.9

From what I found searching the web, 12.9  is the strongest metric grade made and is alloy steel, hardened and tempered. Interesting the bottom bolts are one grade lower. They should also be 12.9

[vanagonturbo]

The increased strength of the top bolts is due to the fact that they are smaller in diameter. Neither bolt is a torque to yield. They can be reused multiple times.

Nut-N 903 237 04

[92EcoDiesel Jetta]

Can you take one of the pieces of bolt with the nut on and putting in a vice, will the nuts come off? The exposed thread looks from here in pretty good condition, so it is a bit of  a mystery.

The torque required on these bolts, or at least similar ones on a' Quantum' are between 48 and 52 lb ft.  ONLY.

I have an ex brotherinlaw who would quite happily apply this kind of torque to an M6 valve cover bolt, and 100lbft + via a half inch drive socket set to an M10 lock nut.

I will play with getting the nuts off the broken stud after I get my Jetta back together.

[92EcoDiesel Jetta]

The increased strength of the top bolts is due to the fact that they are smaller in diameter. Neither bolt is a torque to yield. They can be reused multiple times.

Nut-N 903 237 04

Thanks for the p/n. I picked up a set of the camber bolts and nuts from RapidParts, not a VW delaer but a VW Audi shop in NY. I thought only VW dealers stocked VW parts? They were 10.9 grade though. I have 2 bottom bolts a friend gave me from an 85 VW and they are marked 12.9. Seems to be a lot of variations in what grade bolts were/ are used

[Fredrikkk]

Why not just get regular M12 bolts and nuts? That's what my friend did, and it still works