Rear Trailing arm NUT size..

[Kraftwerk]

What size is the rear trailing arm (banana end) Nut # 33 in Bentley Manual says M14 but that is the thread pitch, I just need to know what wrench fits that nut. Is it a 22mm?

Thanks.



(sent from the Sears Parking Lot..)

[boyt911sc]

JT,

M14 is the nominal bolt diameter and this means it is a 14-mm x n (thread pitch number). The size of your wheel lug bolts is 14-mm x 1.5 (thread pitch). The three (3) most common thread pitch in our 911 are 1.0, 1.25, and 1.5. HTH?

Tony

[DRACO A5OG]

To the Chassis, Torsion Plates or Drop links? If the Last two 19MM

[JRSIII]

I suspect he's talking about Items 4/6 in the diagram below. These are M14 and should take a 22 mm wrench. Note I haven't personally verified this, but that's what google says. The other two bolts DRACO is referring to are M12 and do in fact take a 19 mm wrench.

[hangar21]

My car is an 87 & is (22MM). I had to drill, grind & saw to remove nut & bolt (see pic) because PO had banana arm replaced after accident. Nut had "rounded" Edges & was a PITA to remove. I bought a 22MM socket at Loews (cobalt?) and cut (shortened 1/4") it on my lathe, this helped with clearance issues when reinstalling. Re-installing was much easier! Hope this helps.
Terry

[Kraftwerk]

Thanks.

Wow, this NUT is really stuck - - AND hard to access. I am sure the other side of the car will be just as difficult.
Now I know why people say the rear suspension is harder to tackle than the front. (front is done)

Hangar21.... I think I am going to have to do what you did and cut down / fabricate a shortened socket... there is not a lot of room on the nut side, so the shaved socket sounds like a good plan. Unless anyone else out there has some kind of magic tricks up their sleeve... I am totally stuck ~ the shock tower nut is disconnected, the trailing arm is removed, the axel is 1/2 off so I am REALLY stuck... I can't even roll / move my car at this point, so its not like I can simply bring the car to an 'expert'.
Crap, I am really 'up the creek', the learning curve just got steeper!

HELP!

Since misery loves company, this thread is really good: Another trailing arm bolt removal question

and this one : Trailing arm monoball installation


The other thing is working with jack-stands really makes you want a lift, in fact, it justifies owning a lift.
Everyone with a lift you should pat yourselves on the back right now.

[hangar21]

I'll be able to measure & take pix of my socket (tomorrow). Your welcome to borrow. I had to use a drill & then a Grinder on my dremel tool to remove bolt head (PITA). Then I used a punch to "drive" bolt toward transmission-far enough to expose nut. Now comes the most laborious part! With the nut & bolt exposed, I duct taped one end of new hack saw blade & began the slow process of cutting the nut off. This took a long time! I recommend to saw " slow & steady" & take lots of rest breaks! It will eventually work & with nut removed you can use a screwdriver to push the bolt back into the Banana arm. You can remove the entire Arm. FYI-I had everything removed, shock, brake disc, torsion plate & drive axle. My car was on Jack stands, I would have given anything for a lift! Hope this helps!
Good luck,
Terry
(817) 480-0635
hangar21@me.com

[Kraftwerk]

yeah, take a picture of the socket would be interested to see that.

[chris_seven]

Once you have it in parts there are a couple of ways to help with the problem in the future.

There are two style of Metric Fine Nyloc Nuts- P Type which is 16mm high and uses a 22mm AF spanner

The second is a T Type which is 12mm high and also uses a 22mm AF spanner.

It is relatively easy to find the T Type in a A4-80 Grade Stainless Steel which would normally be used with a Grade 8.8 Bolt and should be strong enough.

With a suitable ceramic grease they should be relatively easy to undo the next time round.

The other nut that works is a K-Nut - prevailing torque type nut.

The M14 x 1.5 versions are 12mm high and use a 16mm AF spanner - very strong with a 23mm dia flange to spread load.

For use on our Rally Cars we make Titanium Bodied Monoball with a 5/8" diameter bore spherical bearing and a spacer to allow us to use a 9/16" diameter AN Bolt.

We use a grip length so that both sides of the mounting clevis engage with the 'grip' of the bolt and then use an Imperial K nut.

[hangar21]

Pic of "normal socket (1 1/2") next to my modified socket (1 3/16").
Terry

[Kraftwerk]

"We have tools to fix tools"

Thanks Terry, just what I imagined.. determined to get this nut off.

chris_seven, Thanks for the nut-information. Had to look up "prevailing torque type nut" and "Imperial K nut" also known as a Surface-Bearing Lock Nut ( found info here: http://www.fastenerexperts.com/lock-nuts/ )

So, a smaller bolt, eh? with a sleeve... ever had any issues with that? I was thinking about shortening the bolt by cutting it, just to be able to get the socket seated and the wrench in there.

Titanium Bodied Monoball : I think we need to see a picture of that!
Thanks guys..

[chris_seven]

9/16" diameter is 14.28 so is a little larger than the stock 14mm diameter and why we use a 5/8 NMB Stainless Steel Bearing.



Sorry about the crummy photo.

The housing is 6AL4V Grade 5 Titanium.

The NMB bearing is press fitted against a shoulder with the interference, hence radial compression specified by NMB.

It is retained using a Smalley's Double Spirolox Stainless Steel Retainer (Don't like Snap Rings).

The bearing and the Spirolox are pre-fitted.

The weather seals are Seals-It parts and the misalignments spacers are hard anodised 7075-T6 Aluminium Alloy.

We supply shims to adjust the width of the Misalignment spacers to deal with the variation on width of the torsion bar brackets.

We also retain the Monoball in the arm using a Smalleys' Spirolox Double Retainer instead of a Snap Ring.

And we supply shims to make sure of the correct fit in the arm.

All of the internal and external shims are also stainless steel.

[Kraftwerk]

Thanks chris_seven,

Larger bolt than stock seems wise. Smalleys' Spirolox Double Retainer : had to look that one up, too.
Nice kit. You had me at Titanium.

[chris_seven]

The main benefit of the AN bolt is the 'grip' length which you can buy in 1/16" increments.

This means you can arrange the bolt length so the shank fits though both sides of the clevis on the torsion bar tube.

The Porsche bolt us the thread through one side and the shank though the other.

I do understand that providing it is all torqued up tightly this is OK as the clamp force is sufficient but on Gravel Rally cars I just like the extra security.

[donporfi]

Is it possible to break that nut with a nut splitter ?

[Kraftwerk]

I would say no, it's a BIG nut and maybe its flanged besides there is not a lot of room to access the nut. A ratchet wrench does not even fit in there, even w/o a socket. The '84 and later cars have more room between the bolt and the tranny so you can actually use 'normal' tool to remove it. imagine that! I am thinking with the SC a partial engine drop is the only way, besides cutting.

[bugstrider]

Thread bump on a good topic. I'm at this stage of removal and looking at a good solution for removing the nut from the bolt. The bolt head is 22mm on our car and I will assume it's the same on the nut.

Thinking on a usable solution, has anyone taken two 22mm box wrenches, using the enclosed side and cut the head off and then weld that piece to the other 22mm head? Essentially, creating a double thick enclosed box wrench? Thinner than a socket but still deep enough to get a bite on the bolt.

[bugstrider]

Originally Posted by hangar21

Pic of "normal socket (1 1/2") next to my modified socket (1 3/16").
Terry

If you could just confirm that you were still able to get the socket into the confined space between the nut and transmission?

Cheers

[Kraftwerk]

...Yeah, well, if there was a way I could talk you out of this I would....this has been a particularly frustrating stumbling block on my rear suspension re-fresh. The amount of space / angle-of-access is different on each side, everything except the size of the nut presents a new problem. On the passenger side I cut-down a socket so it would be lower -profile and fit in there with the wrench attached then I went at it with a leverage pipe attached to socket wrench after liberal spray of Penetrol 24 hrs previous. . It took a could of days (!) to figure it out but when when I finally loosened the nut the sun shone brightly down and a fresh breeze seemed to fill the room. Then I moved on to the drivers-side where there is even a bit less room and it is VERY close to fuel lines (!) accelerator pivot, clutch cable. The only real advice I can give is that this would be way-easier if you dropped the engine transmission, thats what the pro's do, I am sure. This project is NOT in 101 projects book for a reason...it's damn-near impossible!
Ha! ha!!
Let us know how it goes..

[Kraftwerk]

Heres a link to (an Instagram post) of how I modified the socket:

https://www.instagram.com/p/BMZbbLDA18h/?hl=en&taken-by=frequently_jt

short film...harsh soundtrack.