Banana/trailing Arm bolt is too damned short....

Ryan1938 · 10-06-2023, 09:16 AM

I recently bought a '70 that has been a race car most of its life. Sometime in the 80's, the car was imported to the US, raced some more, and then the owner (Larry Wilson) decided to put it back on the street. During this process, he lost interest and I ended up with the car.

Anyway, I've been putting it back together the past few months and it has been going quite well.

However, this morning I was under the car messing with the suspension and getting everything prepared for an alignment and corner balance when I noticed something kind of scary. Essentially, the bolt that holds the banana/trailing arm onto the torsion bar tube is too damned short on the passenger side. Both sides have been reversed so I can get them out without pulling the motor... but yeah, the bolt on the passenger side isn't long enough to engage all of the threads on the lock nut.

I really don't wanna take the rear suspension apart... Can anyone think of any easy way of replacing that bolt without tearing everything apart? The bushings on both sides look fine...

boyt911sc · boyt911sc's Garage

You will get better response regarding your predicament if you post some pictures.

Tony

Dpmulvan · 10-06-2023, 10:11 AM

If nuts are on the inside you should be able to change them out, otherwise you’ll have to cut the old bolts off and replace.

Ryan1938 · 11:57 AM

On closer examination and after some research, I'm thinking whoever threw this together cut the bolt shorter as torsion bar tubes in '70 didn't have the reliefs in them to allow a longer bolt to get through from the opposite side. Check it out:

I just don't think they left enough thread for comfort...

I wonder if these would work for me:

https://www.wevo.com/Products/SuspensionProducts/WevoSuspensionProducts-EZPins.htm

***

Also, is it safe to take the existing bolt out if I wedge something between the banana arm and it's housing in hopes of keeping it aligned for when I put the new pin in?

Sorry for the stupid questions...

75 911s · 75 911s's Garage

I think your alignment will be fine. The WEVO pins are an elegant solution. I would proceed with those.

stownsen914 · 10-07-2023, 10:04 AM

It's hard to tell from the picture how many threads are protruding on the bolt, for the nut to grab?

Ryan1938 · 10-07-2023, 10:56 AM

Quote:

Originally Posted by stownsen914

It's hard to tell from the picture how many threads are protruding on the bolt, for the nut to grab?

Zero threads are protruding. It’s a solid two threads from being flush with the nut.

jimtweet · jimtweet's Garage

It appears to be the right bolt, BUT the wrong nut. The nut should be a shallow/thin lock nut. It’s also what I believe is called “JIC” where it’s a smaller circumference.

Bolt should be 22mm and nut should be 19mm

I won’t be back in my shop Till tomorrow but I can send pic

boyt911sc · boyt911sc's Garage

Quote:

Originally Posted by jimtweet

It appears to be the right bolt, BUT the wrong nut. The nut should be a shallow/thin lock nut. It’s also what I believe is called “JIC” where it’s a smaller circumference.

Bolt should be 22mm and nut should be 19mm

I won’t be back in my shop Till tomorrow but I can send pic

Jim,

Are you sure it is a M22 bolt used in 911 trailing arm? The SC and Carrera 3.2 trailing arms are only using M14 bolts. Hope it was a typo.

Tony

Ryan1938 · 10-07-2023, 01:09 PM

Quote:

Originally Posted by boyt911sc

Jim,

Are you sure it is a M22 bolt used in 911 trailing arm? The SC and Carrera 3.2 trailing arms are only using M14 bolts. Hope it was a typo.

Tony

Oh man... that would be GREAT... I haven't placed my order for the EZ pins yet.

THANK YOU!

phelix · 10-07-2023, 01:14 PM

Quote:

Originally Posted by boyt911sc

Jim,

Are you sure it is a M22 bolt used in 911 trailing arm? The SC and Carrera 3.2 trailing arms are only using M14 bolts. Hope it was a typo.

Tony

Is he referring to wrench size rather than the thread diameter? Would seem to be the case…

Ryan1938 · 10-07-2023, 01:16 PM

Quote:

Originally Posted by jimtweet

It appears to be the right bolt, BUT the wrong nut. The nut should be a shallow/thin lock nut. It’s also what I believe is called “JIC” where it’s a smaller circumference.

Bolt should be 22mm and nut should be 19mm

I won’t be back in my shop Till tomorrow but I can send pic

I meant to quote you, but was too slow... In any case, confirmation with a pic would be great as I haven't ordered the EZ pins yet...

jimtweet · jimtweet's Garage

Quote:

Originally Posted by phelix

Is he referring to wrench size rather than the thread diameter? Would seem to be the case…

Yes wrench size

jimtweet · jimtweet's Garage

Seen both of these styles used not sure which pertains to the correct year, along with a washer