Dislocated my upper control arm shaft- how to fix?

[Michael L.]

Guys,

I recently completed the resto on my 69 L46 coupe and my son has been road testing it for me. He called a couple of days ago because the steering went wonky and he feared something went wrong. When I get to where he pulled over I popped the hood and found that the drivers upper control arm had dislocated. Fortunately, it didn't result in a catastrophic failure and serious car damage. I think that it was torqued properly but the end bolt obviously backed out allowed the shaft to dislocate. see the attached pic. I'm thinking that I might be able to shift the wheel forward to allow the shaft to be inserted back into the bushing. I can then re-insert the bolt and this time I'll loctite it. Anyone have any suggestions or advice on this? Ever see this? thanks for any input.

Mike

dislocated upper ctrl arm.jpg

[David H.]

Re: Dislocated my upper control arm shaft- how to fix?

Michael

Photo of other side and complete (both sides in one image) please.

Dave

[Thomas N.]

Re: Dislocated my upper control arm shaft- how to fix?

Michael
The issue is that the shaft is unable to retract back enough into the other bushing to allow the room to engage the end you are showing to slide into the bushing. When you install the bushings, the shaft needs to be in position and press the bushing in and engaging the shaft at the same time. If the bushing is complete (inner sleeve and all) you are going to need to remove the upper a arm, and the cross shaft and press out the bushing and reinstall. It appears that the inner sleeve of the bushing is missing, which should be bonded to the bushing.

Your son is great! It was good thinking on his part when he felt something wrong and pulled over. I know of many that would of kept driving. You raised him well!

[Mark E.]

Re: Dislocated my upper control arm shaft- how to fix?

How could this scary failure happen?? Perhaps a bushing shifted or popped out (which from the photo, it clearly didn't) allowing the cross shaft to come out? Or maybe the bushings are not fully seated? Or the A-arm suffered a structural failure, allowing it to flex enough under load for the cross shaft to come out?

Check the A-arm for cracks or other defects that could cause this failure. And check that the bushings are properly installed and fully seated.

It's best to remove the A-arm from the car to check and repair this.

Carefully inspect the rest of the suspension and steering also.

[Michael L.]

Re: Dislocated my upper control arm shaft- how to fix?

OK. For the removal of the A-arm, I read in the CSM the process for removing the upper control arm and it doesnt seem to address the front spring at all. When I installed the a-arms, granted it was with just the bare chassis, but it was a total project to get the spring compressed to install the a-arms. What do I do with the spring when I take the upper a-arm off???

Mike

[Michael L.]

Re: Dislocated my upper control arm shaft- how to fix?

sorry I just looked over my assembly pics (it's been a while since I did that part) and realized that only the lower a-arm contacts the spring and that's why the spring isn't addressed in the upper a-arm removal process. that obviously makes removing the a-arm light years easier than I thought and that's what I'll do. I'll also take and post pics of the whole a-arm as well as the passenger side for comparison.

FWIW I had both upper and lower a-arms restored and the ball joints riveted in by one of the vendors, not certain which one (maybe Bair's?) so I didn't assemble the pivot shafts. It's possible I forgot to torque the end bolts once the car was at ride height. The restoration process was so slow and took nearly 20 years that much of what I did I have long since forgot. I will definitely check the passenger side after this tho. the lowers were definitely torqued.

Mike

[Thomas N.]

Re: Dislocated my upper control arm shaft- how to fix?

It would be nice to see a closeup of the bushing. It doesn't look like there is an outer metal sleeve like a factory bushing. Usually a factory type bushing has a metal inner sleeve, a metal outer sleeve, and rubber bonded between them to form a single unit. Hard to tell from the picture and my eyes that spend way too much time in front of a computer. Could these be polyurethane type bushings?

To me, the safest way to remove the spring is to remove the shock absorber and put a piece of threaded rod up through and compress the spring. I'm enclosing a link to a you tube video showing the process. You can access and turn the nut from the inside of the engine compartment with an installed body on the frame. https://www.youtube.com/watch?v=K0COGAbOdi0

Hope this helps!

[Michael L.]

Re: Dislocated my upper control arm shaft- how to fix?

Thanks Thomas. That's how I installed the springs, but again I don't believe I need to mess with the spring if I only have to do the upper a-arm.

100_0549.jpg

[Thomas N.]

Re: Dislocated my upper control arm shaft- how to fix?

I like to use it to start compressing the spring a little, so when you separate the upper ball joint from the spindle, it is contained and doesn't go flying. You would then remove the upper A-arm and then unload the spring. You have the rod and items already. You don't have to. It is all personal preference.

The way I'm seeing things, you are going to need to get the upper a arm off of the car to fix your issue. And you will need to compress the spring to put it back together.

[Leif A.]

Re: Dislocated my upper control arm shaft- how to fix?

It would be nice to see a closeup of the bushing. It doesn't look like there is an outer metal sleeve like a factory bushing. Usually a factory type bushing has a metal inner sleeve, a metal outer sleeve, and rubber bonded between them to form a single unit. Hard to tell from the picture and my eyes that spend way too much time in front of a computer. Could these be polyurethane type bushings?

To me, the safest way to remove the spring is to remove the shock absorber and put a piece of threaded rod up through and compress the spring. I'm enclosing a link to a you tube video showing the process. You can access and turn the nut from the inside of the engine compartment with an installed body on the frame. https://www.youtube.com/watch?v=K0COGAbOdi0

Hope this helps!

Michael,
Obviously, something went painfully wrong here. As Thomas stated, the bushing in your picture is missing some of it's parts. I've had the end bolts back off before but even if they fell out you wouldn't have failure as yours appears. If the bushings had been correctly installed, the metal sleeve of the bushings wouldn't have allowed the shaft to come away from the control arm...there just wouldn't have been enough room for it to fall out.
Pictured below is a upper control arm bushing. Compare it to what yours looks like and you'll see what we're talking about.
Again, glad your son was smart enough to pull over and he's OK and the car will be OK.

[Jeffrey S.]

Re: Dislocated my upper control arm shaft- how to fix?

Michael,
That type of failure is very scary. It happened to me on my '69 some 30 years ago, long before the restoration phase of my ownership began. I had installed polyurethane bushings (I know, I know!). The only thing holding these together was the end bolt which unscrewed itself and wham. The main reason I'm posting is to tell you that when you remove the upper control arm you need to support the lower one when you disconnect the steering knuckle from the A-arm. I just use an hydraulic jack. The other thing I can tell you is that getting the a-arm out past the studs can be a challenge. If you can knock the studs out of the frame it's OK. It's been a while since I have done this so there are probably other things I have forgotten.
Jeff

[David M.]

Re: Dislocated my upper control arm shaft- how to fix?

All chassis and drive train fasteners get a light application of blue removable Loctite then torqued with a NIST calibrated torque wrench.

[Duke W.]

Re: Dislocated my upper control arm shaft- how to fix?

You can remove the upper A-arm without touching the spring. Put the front end on jackstands, either on the frame front jack points or under the lower A-arms. Loosen the rear upper A-arm bushing bolt. Remove the cotter pin from the upper ball joint stud and loosen the upper ball joint nut to the last couple of thread turns on the stud. Then use a BFH to whack the side of the knuckle next to the stud bore. The shock should cause the tapered stud to loosen, then remove the nut, separate the stud from the knuckle and carefully lay the knuckle over until it reaches the limit of lower ball joint travel, and better yet, figure a way to tie it up so it doesn't rotate the lower ball joint to the limit of travel.

Then you can remove the upper control arm shaft from the frame. Be sure to record the number of shims on each stud.

I can't tell from the photo, but something looks funky about that bushing. If this bushing is defective or the wrong part you better check the other one on that A-arm and also carefully inspect the other side upper A-arm for integrity and correct bushing.

Duke

[Mark M.]

Re: Dislocated my upper control arm shaft- how to fix?

Michael, it's not worth any short cuts. Spring needs to be compressed a little more than cars weight offers for safety and to remove and reinstall upper arm over top rubber bumper. A good spring compressor is easily found. I've seen springs pop loose and it's dangerous.

[David H.]

Re: Dislocated my upper control arm shaft- how to fix?

Just a WAG as to what has happened.

Installer drove BOTH bushings into control arm before realizing cross-shaft should have been inserted first.

Then, removed bushing inner sleeves, now allowing cross-shaft sufficient clearance to slide up and into bushing.

Bubba at work: Who drives these cars anyhow? And washers plus end bolts will keep everything together!

BTW: what does other side control arm upper, and both sides lower control arms look like?

I'd take that suspension completely apart and see just what you've got. Did the same folks do rear suspension as well?

Dave