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Discussion Starter #1 (Edited)
What's Up Guys,

So I'm in the process of replacing my control arms and bushings this weekend and while sifting through the previous DIY's I noticed a lot of people were having trouble separating the FCABs from their aluminum carriers. You can buy pre-pressed bushings if you want, or you can save yourself about 50% by separating the bushings yourself and reusing your old carrier.

I figured I'd share a trick we use in forced induction to remove firmly seated steel bearings from aluminum s/c housings. Simply put, the "trick" is to put the entire assembly in your oven.

The carrier is aluminum. The bushing itself is mostly steel and rubber. Aluminum is a softer metal and will expand slightly faster than the steel bushing. This will allow you to separate the parts with minimal effort. This method has advantages over using a blowtorch since it will heat the entire part uniformly instead of creating hot spots which might damage the metal. Also, no special tools are required other than a mallet, a chisel, and a vice (or a beefy set of locking pliers) so cost is minimal.

DIY:

1) PREHEAT your oven as hot as it will go. About 500 degrees should do it.

2) Give the parts a quick scrub with soap and water to remove any traces of grease or oil that may give off fumes when exposed to high heat. A soapy Brillo pad works well.

3) Assemble all your tools and test fit your vice/locking pliers before heating the parts. You don't want to waste time fumbling with equipment and letting the parts cool off after you remove them from the oven.

4) Place parts in the oven for a 15 minute heat soak. Placing them on a pan keeps everything together and easy to handle.


5) Remove parts from oven with care, THEY WILL BE HOT. Get a FIRM grip with your locking pliers and give the bushing a few solid whacks with your mallet. It should start sliding until it's flush with the carrier.


6) Next, set the part in your vice and use your chisel to tap out the black rubber guts of the bushing. Do this first. Once the guts are removed then start tapping on the outermost steel ring that remains in place. The interior of the bushing is essentially a steel cage coated in rubber. It's very strong. It will probably come out in two pieces as shown in the pic below. Knocking these parts out first will allow the the outermost steel ring the give it needs to slide out. Keep tapping until it pops out.







The clock on the oven tells the story. After a 15min heat soak I got the first bushing tapped out in about 5mins. No cutting, grinding, metal bending or makeshift Home Depot tools required. Time is of the essence with the this method. You will get about 8-10mins of work time after each heat soak. If the parts seize up and stop moving when you tap on them it means they have cooled off and shrunk. Try returning them to the oven for another soak and giving it another shot.

That's pretty much all there is to it. Good luck!
 

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Discussion Starter #4
very cool!

Question: When replacing the bushing do you reheat the carrier to get the new bushing to fit in place?
I didn't need but you certainly could. I manged to coax the new bushings into place with the mallet while the parts were still warm.

Conversely, I suppose you could put the new bushings in the freezer over night to shrink them a bit prior to installation as well. That might sound crazy but we do it with bearings. It's all the same principal. A chilled bearing will drop right into a warm carrier so easily it may even seem too loose.

When everything returns to room temp Zeus himself could not pull them apart!
 
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