Broken LCA pivot mount!!
Yikes!!! As others have said, it's not uncommon for this to happen.
This is going to be the biggest issue. With such a large hole it will be harder to line everything up than if you just had the welds break. Is the other side intact?
If the other side is intact, you can take measurements from it. What I would do is press the pivot pins out of your LCA's. Then you can install the pivot pin back into the pivot tube, so you can use a level and a square on the back of the LCA pivot to get the pivot tube back into the right spot, comparing the angle on the LCA pivot to the other side to ensure it's lined up right. Once that is done you can tack weld it into place, and go about reinforcing the area around the tube. I reinforce the LCA pivot tubes on my cars for this exact reason. The first time I did it I used a Firm Feel K-frame reinforcing kit, which includes all the gussets you need for the whole K frame. Since then I just make my own out of 1/8" or 3/16" steel. The pivot tubes can be reinforced with a heavy duty washer from the hardware store, you want to get one that has a 1-1/8" inner diameter. The HD washers in that size are almost 3/16" thick and work great, you just section the washer so it sits flush with the top of the K frame and then run a bead around the inside diameter, just grabbing the outer edge of the pivot tube with the weld. Done correctly it doesn't interfere at all with the LCA pivot, so it won't change anything regarding the alignment or suspension movement. You do have to be careful, if you burn through the pivot tube you'll obviously have to clean the inside of the tube so nothing interferes with the pivot. A couple of pictures of the K's in my Duster and Dart
As far as the LCA pivots go, as already mentioned they need to be pressed out. If you have a 12 ton press at home that will work, or you'll have to take them somewhere. Depending on how wiped out the bushings are sometimes they'll just pull out, I've actually had the arms fall off the pivot pins before when I pulled the torsion bars. You can also use a torch to melt the bushing, but that gets pretty messy.
As for reinstallation, it depends a lot on whether or not you're going to stay with rubber bushings or go to polyurethane or Delrin. Rubber is actually the most difficult as it will require removing the old outer bushing shells. Poly and Delrin are more expensive because to really do that right you need adjustable strut rods and greaseable pivot pins. There are pros and cons to all of them, it just depends on how you're going to use the car and what your own abilities are to do alignments and things like that.
I took a bunch of pictures when I installed the BergmanAutoCraft Delrin LCA bushings in my QA1 lower control arms. A lot of that process is the same, as the Delrin bushings also require removing the old outer bushing shell. I use a large tap for removing the shells, it makes pulling the shells super easy. Here's the post in my build thread
My "new" '74 Duster- or why I need a project like a hole in the head
And a couple pictures of the removal process...
The LCA, pivot pin and bushing assembly completely disassembled, this was done by pressing the pin out with a 20 ton press. Everything separated cleanly as these were all new parts. Be sure if you do the pressing that the LCA is properly supported so you don't bend anything.
Threading the tap in
Pressing the shell and tap back out. You can see the plates under the LCA, the other thing underneath it is a really large nut from a Dana 44 assembly that just happens to be larger than the outer diameter of the bushing shell but smaller than the end of the LCA, so it supports it perfectly.
The shell after removal. After that the reassembly is a bit different because of the Delrin bushings.
Yikes!!! As others have said, it's not uncommon for this to happen.
This is going to be the biggest issue. With such a large hole it will be harder to line everything up than if you just had the welds break. Is the other side intact?
If the other side is intact, you can take measurements from it. What I would do is press the pivot pins out of your LCA's. Then you can install the pivot pin back into the pivot tube, so you can use a level and a square on the back of the LCA pivot to get the pivot tube back into the right spot, comparing the angle on the LCA pivot to the other side to ensure it's lined up right. Once that is done you can tack weld it into place, and go about reinforcing the area around the tube. I reinforce the LCA pivot tubes on my cars for this exact reason. The first time I did it I used a Firm Feel K-frame reinforcing kit, which includes all the gussets you need for the whole K frame. Since then I just make my own out of 1/8" or 3/16" steel. The pivot tubes can be reinforced with a heavy duty washer from the hardware store, you want to get one that has a 1-1/8" inner diameter. The HD washers in that size are almost 3/16" thick and work great, you just section the washer so it sits flush with the top of the K frame and then run a bead around the inside diameter, just grabbing the outer edge of the pivot tube with the weld. Done correctly it doesn't interfere at all with the LCA pivot, so it won't change anything regarding the alignment or suspension movement. You do have to be careful, if you burn through the pivot tube you'll obviously have to clean the inside of the tube so nothing interferes with the pivot. A couple of pictures of the K's in my Duster and Dart
As far as the LCA pivots go, as already mentioned they need to be pressed out. If you have a 12 ton press at home that will work, or you'll have to take them somewhere. Depending on how wiped out the bushings are sometimes they'll just pull out, I've actually had the arms fall off the pivot pins before when I pulled the torsion bars. You can also use a torch to melt the bushing, but that gets pretty messy.
As for reinstallation, it depends a lot on whether or not you're going to stay with rubber bushings or go to polyurethane or Delrin. Rubber is actually the most difficult as it will require removing the old outer bushing shells. Poly and Delrin are more expensive because to really do that right you need adjustable strut rods and greaseable pivot pins. There are pros and cons to all of them, it just depends on how you're going to use the car and what your own abilities are to do alignments and things like that.
I took a bunch of pictures when I installed the BergmanAutoCraft Delrin LCA bushings in my QA1 lower control arms. A lot of that process is the same, as the Delrin bushings also require removing the old outer bushing shell. I use a large tap for removing the shells, it makes pulling the shells super easy. Here's the post in my build thread
My "new" '74 Duster- or why I need a project like a hole in the head
And a couple pictures of the removal process...
The LCA, pivot pin and bushing assembly completely disassembled, this was done by pressing the pin out with a 20 ton press. Everything separated cleanly as these were all new parts. Be sure if you do the pressing that the LCA is properly supported so you don't bend anything.
Threading the tap in
Pressing the shell and tap back out. You can see the plates under the LCA, the other thing underneath it is a really large nut from a Dana 44 assembly that just happens to be larger than the outer diameter of the bushing shell but smaller than the end of the LCA, so it supports it perfectly.
The shell after removal. After that the reassembly is a bit different because of the Delrin bushings.
