Lower control arm issue

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supertruck

supertruck

Unretired Old Fart stock car racer
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Attached photo shows my left side LCA on my 73 Dart Sport. You can see that the LCA is not seated all the way onto the pivot shaft. I rebuilt the entire front suspension using the PST Super kit. Everything went together well except for the LCA not seating all the way on the pivot arm. The passenger side does not have this issue. At first I thought that the torsion bar might force it to seat once I installed it, but no luck. Except for the PST parts, everything that went back in is what came out. Idid add the LCA reinforcement plates to each arm, but they were welded per the PST instructions. Any ideas on what is causing this LCA not to seat?
LCA driver's side.jpg
 
I did my E body and getting ready to do my A body.
I pressed LCA bushing onto the pin first.
Then press the pin / bushing assembly into LCA.
Also I noticed A and E pivot pins are different.
I welded the box plates on too... No problem.
It looks to me you used Poly bushings... Did you remove the old sleeve from the pin
 
Dfr360cuda said:
Did you remove the old sleeve from the pin
Click to expand...

That's what I was thinking when I saw it.
The directions you wrote are great for OE bushing replacement, but poly is a little different because it all just slips together.
They are really tight if you leave the sleeve on the pin, then they like to squeak if you force it on anyway.
 
I removed the stock bushing sleeve from the LCA before installing the poly bushings. The new pivot shaft fits snug but not tight by any means. Guess I'll have to disassemble everything, then retrace my steps and see when the arm pulls off the shaft.
 
When I rebuilt the LCAs for my Challenger I used poly bushings, and the original inner sleeve stayed on the pin, the poly bushings weren't "stepped". That's why you can buy 2 different types of pins, 1 turned down for rubber with the inner sleeve and the other full diameter the entire length for poly (or the even more solid nylon ones). The peices with poly bushings pushed together pretty easy, but I found they would also allow the LCAs to shift back and forth between the pin and the torsion bar while driving. For my last couple rebuilds I've used rubber for that reason. Adjustable strut rods helped keep everything in place as well.
 
Thought about the adjustable strut rods. Figured they were more for alignment issues than for correcting a problem like mine. Are you glad you got yours? At first I thought maybe the LCA warped when I welded the reinforcement plates but both arms side by side look good so I don't think it's that.
 
I'm thinking about going with rubber also if I can't fix this.
 
Yep, really happy. I got the ones from Reilly Motorsports, and they adjust to take out the bind that sometimes happens during the suspension travel. No bushings into the K-frame either, they have solid "pucks" and a flexible joint.
 
I have never used poly bushing in the lower control arms, but it has been my understanding that when you do use the poly bushing you need to leave the outer shell in the lower control arm and the inner shell on the pivot shaft.
 
694spd said:
I have never used poly bushing in the lower control arms, but it has been my understanding that when you do use the poly bushing you need to leave the outer shell in the lower control arm and the inner shell on the pivot shaft.
Click to expand...

The directions that came with mine said to remove the inner sleeve.
 
When I did mine recently there was a bit of rubber in the torsion bar hole that prevented me from getting the torsion bar all the way home. Might help to check??
 
694spd said:
I have never used poly bushing in the lower control arms, but it has been my understanding that when you do use the poly bushing you need to leave the outer shell in the lower control arm and the inner shell on the pivot shaft.
Click to expand...

I've used poly bushings on all of my cars. The ones I've used all required both the inner and outer shells to be left in place. That said I use greaseable pivots on mine and not stock pivot pins, but the diameter of of the stock pins with the shells on is the same.

I also use adjustable strut rods on all of my cars. The original strut rods were a "one size fits most" situation that worked ok because of how much play there is in all the rubber bushings. If you go to poly you eliminate a lot of that play, and the strut rod has to fit the car more accurately than most of the stock ones did. I've had no issues with the poly bushings on any of my cars.
 
The PST instructions said to remove both the inner and outer bushings. I did notice that the pivot pin on the passenger side fits tighter than the one on the drivers side. In fact, if I pick up the driver side by the pin, the LCA will fall out, it's that loose. Guess if I can't diagnose it, I can switch to a rubber bushing on that side, which I hate to do cause I wanted the poly all around. Not having experience with the adjustable strut rods, I don't know if that can be used to force the LCA back on the outside, and forward on the inner side. By the way, both arms were blasted and cleaned so there's nothing that might be stuck in the torsion bar seat as Scott9990 suggested. Thanks for all the help guys.
 
If you've removed the bushing shells, buy a set of Peter Bergman's delrin LCA bushings. You'll still need an inner sleeve though if you reuse the stock pins.

Bergman Auto Craft - Home of the Modern Muscle Car

I have yet to see a poly bushing that didn't need both the inner and outer shells of the old bushings to install. Maybe PST is doing something different now, but all the ones I've seen in the past need the old shells in place, only the rubber is removed.
 
One of mine looked like that too after it was snugged in. It's been like that since 1999, 125,000 plus miles. It aligned just fine.
My new pins were a slip fit into the PST bushings as well; hasn't been an issue. The shanks on My new pins were the same size as the factory pins with the inner shells still on them.All pins seated properly in the 340 Duster K. All pins, dimensionally were close to identical. I barely gave the odd appearance a second thought. I put a little extra grease in the T-bar socket, and drove it home with the T-bar.I was an alignment tech at the time, and the alignment was not affected. It seemed to stay there. I haven't looked at it for many years, so cant say where it is today.
 
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After all this, I'm guessing I should have at least kept the outer shell in place. When removing the old rubber, the inner shell stayed with the old pivot pin, so I don't know how I could have reused that one with the new pins. Waiting on a response from PST now so I'll see what they say.
 
From the pictures that you posted here as well as on the FABO site. It looks as though the pivot shaft is not completely seated. To start when using the lower control arm bushing in POLY you will need to re-use your inner and outer sleeves from your control arm bushings. In many case when you press our the old bushing and pivot shaft the outer sleeve will stay in the control arm. You may need clean out any residual rubber using a heat gun and wire brush. once that is cleaned out you can install the new poly bushing. Then you will need to install your pivot shaft. Now I do see that you purchased new pivot shafts and when using the poly bushing you will need to reuse the inner sleeve. Now in the front end kit. There should have been two rubber lower control arm bushing supplied. We supply those for that purpose. Meaning to sacrifice for their sleeve. Or in some case customers like to use the rubber ones for the lower control arms. Once you have the sleeve installed on the new pivot shaft then use the polylube supplied and grease the shaft and press it into the lower control arm. All of this will be a press fit.

I would disassemble and look for obstructions to start. Please lest me know how you make out.

Thanks
James From
PST Marketing
1-800-247-2288
 
Thanks James. I did see the two rubber bushings in the kit, wondered what they were for. I'll have to use them. When I disassembled the old pieces, I burned out the rubber and the inner sleeve stayed on the old pivot shaft so it's toast. I also removed the outer sleeve so I'll be starting from scratch with the rubber ones you supplied.
 
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