Axle bolt with 14 mm hex head, 85 ft-lbs + 180°

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How long a breaker bar do you estimate I'll need? I'm thinking 3 feet minimum, or I'll ruin my neck and back which aren't doing great at the moment. Don't wanna end up like Pablo...
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How long is the working area of the bolt ? (That's face of the nut to face of the clamping surface).

What's the thread pitch ?

root diameter of the bolt ?

It's (pretty) obviously yielded in it's final condition. Not reusable.
 
"It's (pretty) obviously yielded in it's final condition. Not reusable."

Think Shannow may be a bit confused, know I certainly am. Are you saying head reqires a 14mm socket? or it's a 14mm bolt?(if so,what's socket size? If you are refering to tightening to 85ft/lbs., then an additional 180deg to tight, I don't believe either will withstand that much torque. What's this part of?

Bob
 
Not confused at all.

There are materials that will handle those loads, and the longer the bolt/stud, the less stress is imposed on the fastener.

I think the specs aren't right for any sort of reasonable application.

But if it's correct, then it's almost certainly yielded, unles it goes from one side of the car to t'other.
 
the diff fill plug on my w123 MB is a 14mm allen socket. It is a dissimilar metal from the diff, and as such, gets stuck extremely hard with use and every time I try to change the lube, its really tough.

I use a 24" breaker bar, 1/2" drive (its just what I have, thus why I use it), and I press on it with my legs, as I cant get it in the gap (car is on the ground) with my arm strength. I checked it and it needs more than 75 ft-lbs to get it to move...

So 3' + is a good idea. If its safe, a standard 24ish length one with leg power ought to do.

JMH
 
Originally Posted By: Shannow
How long is the working area of the bolt ? (That's face of the nut to face of the clamping surface).

What's the thread pitch ?

root diameter of the bolt ?

It's (pretty) obviously yielded in it's final condition. Not reusable.


It's an M14 rear wheel axle bolt with a 14 mm inner hex head: the one on the blue box
The specs you want to know I can check once I have the bolt.

Most of the suspension-related bolts on my Audi are torque-to-yield and one time use (Waiting for a comment, Gary!). A new axle bolt comes with the bearing kit.

Just wondering if a 3 foot breaker bar will be long enough to add a 180° turn beyond 85 ft-lbs. 85 ft-lbs is obviously no problem...
 
I'll check when I get home (did up a spreadsheet where the pertinent details are input).

Assuming that the working part of the bolt is around 3", you'll need every bit of the three feet. (870N on 2'6" was the calced value for a 12mm cross section).
 
Cool, can't wait to see what you figure out. I suppose I should also get a 5 foot steel pipe.
 
still need the effective length and pitch.

thread looks pretty fine, so the torque will come down some.
 
I have had torque-to-yield fasteners on many German cars that required such specifications. In fact, the engine mount hardware on my current VW uses such a fastener.

For a bolt that size; a 3 foot bar should be more than adequate for this job. Naturally, the material type and physical dimensions of the bolt play a major factor.

VW's 130mm X 14mm with 1.5mm thread pitch engine mount bolts are easily installed with the additional 180º of torque. Sometimes they feel great and other times you'll swear you just stripped the threads... but they always turn out perfect.

I wonder why they use that type of fastener?
 
They use them because if the material specs are right, the yield point (and the movement thereafter) is pretty predictable.

STRESS-STRAIN.jpg


see how on the elastic portion of the stress (load) strain (stretch) part of the curve, a small amount of movement is a lot of change in load. Once the yield point is reached, it's sort of flat for a long time.

So if you've got a clamping load (as opposed to one that adds load along the axis of the fastener), torquing to yield gives a fairly predictable result.

You can't use them again, as when you take off the tension, the curve runs back to a stretched zero, parallel to the elastic line...thereafter there is no apparent yield.

A stretch gauge is also repeatable, but not as "generic" as a torque to yield.
 
I can rent a Powerbuilt Bearing Removal&Installation tool set (costs $129 online) for $6 per day from Kragen. I might also need a hub puller, if the hub is damaged. I can rent that tool also.

How hard will it be to get the hub out with a hub puller? This is the original hub and it's been in there for 11 years. What size breaker bar will I probably need? Is this something I should give a shot myself, or does it require a ten foot pole and three sumo wrestlers? Will my 6 foot/190 lbs frame be sufficient?
 
I use a Craftsman 1/2dr 18in breaker bar with a deep socket as a lug wrench for each vehicle, and can easily break loose the 90 to 100 ft/lb lug nuts on any of them with one hand. I'm not that strong, but I do work out on a regular basis. If you don't then a 24in breaker bar should still do fine, otherwise consider having someone else do it as you might tweak something.

Applying force in situations like that isn't much different than doing something like a deadlift, which is the most common strength training exercise that I do. I find free weights best for what I want from my time in the gym, and find deadlifts to be the most practical exercise to do, considering putting kids to bed, loading bags of concrete in a vehicle, building rock walls, changing tires, shoveling ice and snow, etc. If your exercise ends up being the most stress that you typically apply to your body then 'real life' isn't a problem. You keep you core body strength up, and learn to keep tight abs and glutes with a properly arched back when doing something.
 
100 ft-lbs with a 14" breaker bar is handtight to me.

I thought I was talking about pulling off or pressing out the hub. Apparently I was talking about lug nuts (have wheel bolts, by the way). Sorry to waste anybody's time by asking the wrong question.
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Anyway, I forgot to mention it, but I rented the wheel bearing removal/installation tool ($129 deposit and $6 rental fee for one day) from Kragen two weeks ago and replaced the left rear wheel bearing on my Audi. Luckily the bearing came out in one piece and the hub was still good.

The job took me two hours at leisurely speed. The drive axle and the bearing came out easily. Getting the new bearing in was no problem either. I froze the bearing before installing it, but I doubt this was necessary. This is the first wheel bearing to go bad on my car (160k miles/11-1/2 years).

It's nice to be driving without a helicopter chasing me.
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Here is the old 75 mm (OD) F A G bearing with a quarter dollar for size comparison:

rear_wb_160k.jpg


Dust seals removed and bearing degreased. Water and dirt had gotten in. The balls show pitting and they have worn grooves into the race. The old bearing is now a paperweight and impromptu defensive weapon on my desk.

rear_wb_160k_2.jpg
 
Originally Posted By: moribundman
Dust seals removed and bearing degreased. Water and dirt had gotten in. The balls show pitting and they have worn grooves into the race. The old bearing is now a paperweight and impromptu defensive weapon on my desk.

Here's what the Audi service manual has to say about the matter:
Feuer und Wasser kommt nie zusammen
Kann man nicht binden sind nicht verwandt
In Funken versunken steh ich in Flammen
und bin im Wasser verbrannt

FWIW
 
Originally Posted By: Aldaris

Here's what the Audi service manual has to say about the matter:
Feuer und Wasser kommt nie zusammen
Kann man nicht binden sind nicht verwandt
In Funken versunken steh ich in Flammen
und bin im Wasser verbrannt

FWIW


Audi sure know how to make a philosophical and poetic, yet unhelpful, service manual.

(Google Translate)
Fire and water never comes together
Can not bind are not related
In spark absorbed I stand up in flames
And I am in the water burned
 
Actually, it says:

Fire and water don't ever come together.
Can't be bound, aren't related.
Submerged in sparks, I am ablaze
And I have burnt in the water.

(Tenses don't follow rules due to poetic freedom).

PS: That ain't Schiller or Goethe, Zauberflöte.
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