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By worf
#48174
In the Link Pin / Rocker Bar thread someone asked for posts on how to R&R them. I finished pressing new bushings into an rear LCA set before Christmas. It'd been 6-ish years since I last did that and spent non-trivial time re-figuring out how to do it.

So, this thread is as much a how-to thread as it is a how-I-did-it thread so that the next time I can reference it. :burnout:

I'll make a couple posts a day, until I've covered everything.

First, besides the shop press I used the tools below.

The most important is the bushing press set:
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I ended up buying a longer threaded rod for the biggest one 'cause the one's in the kit are too short by about 6" for doing the "coil-over pin" bushings.

Next, the pass-through ratchet set:
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Last, some random press pieces:
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Last edited by worf on Thu Jan 07, 2021 1:43 pm, edited 1 time in total.
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By worf
#48178
Oh.... and a normal bearing separator.

First up are the link pin bushings. Order doesn't matter. This is just the order in which I did them.

Prologue:

In the case of the control arms pictured, they required external restoration and the client wanted new bushings. But since Mark's replacements weren't available originally, I had to 'work around' the link pin bushings. Years ago I was really concerned that pressing out the link pin bushings might result in destroying them. I never do something unless I have an acceptable 'back out' plan. Since they were NLA I never tried. But, with Mark's replacements there's so worry.

Of all the bushings, the link pin bushings are the easiest to R&R. In the future I'd not hesitate to remove the link pins to refinish the control arm even if the plan was not to replace them. They go in and out smoothly. This 928, in particular, since every other part of the work on it has gone sideways, I would have expected the original bushings to fight and self-destruct on the way out. Nope. Like buttah.

Before you start, set your control arms down in the "as installed" orientation and note how each old link pin is "angled". It's possible to install them 180° from the proper orientation. I applied paint marks to each control arm and and new bushing using a different color for each side so that I could line up the arm and bushing on the correct side with the correct orientation. (Note that in this case, I put marks on masking take since the arms had been refinished. If you are going to press out the bushings, then refinish the arm, you'll have nothing but your pictures to guide you. Make sure that they are good pictures.)

Procedure:

First, you have to have a press fixture that won't 'grip' the lip of the bushing. I used a new bushing to "set up" my bearing separator to the minimum separation that would allow the main part of the bushing to pass through.

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Then install the bearing separator between the lip of the old link pin bushing and the control arm housing. Place it on the press and press it out.

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Pressing in the new link pin is straightforward. Select a bushing press piece of the same diameter as the housing, lube up the bearing, and press it in.

However, remember that there's a bolt that goes through the link pin and that you could install the pin 180° the wrong way. So, before you start make sure the orientation is correct and that your bolt holes line up.

Also make sure you can see the hole while you're operating the press so that you know when to stop.

I put a thick piece of rubber between the press and the bushing so as to not mark the housing for the toe bushing.

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By worf
#48325
Next up: The camber bushing.

This bushing is harder to deal with because it's got a lip on both sides that "pops out" past the housing so that you can't get a press piece on the housing as is. I couldn't think of anything clever (if you can, let me know) so I just laboriously cut off one of the lips.

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After that, easy enough to press it out.

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By worf
#48462
Getting the camber bushing pressed in is a multi-step process. The first time I did this, I just tried to press the bushing in. That looked like it would rip the lip off of the bushing. No go. Ideally, you'd have a press piece that was a cone shape - big at one end and the same diameter as the control arm housing at the other - that would compress the lip on the way into the housing. After much googling, years ago, I was unable to prove the existence of such devices. So, I resorted to other means.

What I do is press the bushing into the 54mm piece.

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Then press it into the 52mm piece from the 54mm piece.

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And then finally into the 50mm piece. That's the diameter of the control arm's housing. What's shown below is the 52mm piece. When you press it into the 50mm piece you won't be able to get it all the way in. But, you'll get enough of it in that the press piece will be able to contact the housing.

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At that point you can attempt to use your press. If you've got a jig that can hold the control arm in the right orientation or are equipped with four arms then you can use your press. But, I don't and I didn't have extra arms to hold the control arm and also operate the press. At this point the bushing press set comes in handy.

The 54mm piece is just small enough to support the control arm housing but big enough to let the "lip" of the bushing expand.

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Once you get almost done the 50mm piece will pop off the end of the bushing ...

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... but you can go ahead and press the bushing through until the opposite-side lip pops out.

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By worf
#48463
Shifted wrote: Thu Jan 07, 2021 4:23 pm I'm not saying that this is a good idea, but it's not uncommon to burn out bushings with a torch. Personally, I wouldn't want to burn out the entire thing, but it might be worth considering using a torch to burn off just the lip.
I am aware of that "technique."

The list of items I'm willing to deliberately light on fire in my shop has zero length.
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By worf
#49244
Coil over pin bushings:

Two ways to get them out depending upon the scale of your press:
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Or you can use the bushing press set. The forward bushing is tough to do on the press because there's not much housing available to support a press sleeve. The technique below is also useful to remove the bushing non-destructively when you don't get it pressed-in square the first time.

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These bushings are tough to get in square. The best way I've found is to use an extra-long threaded rod for the press set and get everything perfectly lined up before your start pressing.
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By worf
#67217
Forgot to show final state (and a shameless bump to the top so that new folks see more technical stuff) :typing:

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One other thing:

When you press-in the two pin bushings err on the side of not-enough. When you bolt everything together those big washers at the end of the pins will "finish" pressing the bushings in as far as the need to go. Else, you'll have to press one or more of them back out just a tad to get everything to fit.

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Now, a thinking man or woman would test the fit on a bench and would make sure to use all three of the washers that go in there before declaring victory. :silenced:
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By Geza-aka-Zombo
#67336
Nice! Looks like a lot of work and some special tools. Would this be a service you are thinking of offering?
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By worf
#67367
Geza-aka-Zombo wrote: Fri Mar 19, 2021 7:29 am Nice! Looks like a lot of work and some special tools. Would this be a service you are thinking of offering?
Hadn’t thought about it but, no. Probably not. Was intended as a how-to, not marketing. Got a year backlog for clients as it is.

With shipping both ways it would probably be $300-400 per arm not including parts, ceramic coating and plating etc. For that x2 you can buy the bushing press set and a lot of beer. That, the separator and the gear wrench pass through ratchet is all you need. An x-Ton press just makes it faster. The bushings are about $600 per side IIRC.
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