Top subframe bushing broke off in chassis. How to remove

[BaltimoreBimmer]

If you can't bang it out from the top and end up having to drill it out I wasn't saying use a giant bit to drill the whole thing out, most likely close to a .25 bit . Drill multiple holes around through the outer wall till it's only connected by thin pieces of aluminum. Like looking at a cylinder of a revolver. Once you get there they will just break out pretty easily

that makes more sense, thanks for clarifying for my slow self. That would be a more desirable approach than a dremel. I will have to worry about going too far with the drill bit so that I don't go into the chassis. Luckily my other side came out clean so I can use that as a depth reference.

[gart]

If you can't bang it out from the top and end up having to drill it out I wasn't saying use a giant bit to drill the whole thing out, most likely close to a .25 bit . Drill multiple holes around through the outer wall till it's only connected by thin pieces of aluminum. Like looking at a cylinder of a revolver. Once you get there they will just break out pretty easily

[BaltimoreBimmer]

thanks for the input guys,

Here's what I am dealing with on the inside:



zooming in:



so as you can see, definitely a lot in the way compared to a coupe/sedan

I got my dad to give this a look and he also suggested perhaps a slide hammer. I think I will end up going with what gart said with the drill bits, however I can't see myself finding a drill bit that large (or a drill to hold it!) and my old man has the biggest of drill bit indexes (used to run a machine shop)

On second thought, first I will attempt to get a lag bolt screwed up in there from below, and then fish in a metal rod from above and try to hammer it down:





however, there is a significant bend required to make this work, so I am thinking the rod will give way before the bushing does - here is what the bend looks like:




So I'll attempt that, and then worst case scenario I will have to just drill it out I suppose. Very nervous about scoring the chassis side though

also nru, I always wear proper PPE, perhaps a bit overboard:



the other side came out clean, so I guess I can slowly drill it out and deal with the scoring :( I highly doubt the rod smashing method will work

[nrubenstein]

Carbide bits are your friends for this.

WEAR EXCELLENT EYE PROTECTION. I CAN NOT STRESS THIS ENOUGH. CARBIDE BITS PRODUCE RAZOR SHARP METAL SHARD DEBRIS.

[gart]

Having gone through this in my convertible I'll chime in. What if did was start with a small drill bit from the bottom and drilled around the bushing stepping up in bits till I was close to the thickness of the bushing. Go slow and as varg said you will know when you are through the aluminum. Then I used a small screwdriver and pick to break out the pieces. Wasn't actually that bad and didn't mess up where the bushing sits. You may want to grind it flat and center punch to get a better start. Mine broke further up so I had a rough surface to start with. Let us know how it goes

[ThatM20Guy]

I had to do what varg said to get my bushings out. Thread in a 5/8 (?) lag bolt into the bushing and then I dropped a 3/8 extension and pounded the shit out of it until it dropped.

If you have no access bushing from the top you could maybe use a slide hammer if you have enough room.

[varg]

Not really viable as I have a convertible. Practically no access from above. Perhaps something similar from below?

What? You don't have enough access to do this? I could've sworn there wasn't anything in the way of this hole in my stripped out convertible parts car.

Is it a bad idea to slowly grind away the metal remains with a dremel? Is it realistic to do that and not mar the chassis? Or have they basically formed together as one now.

Not a bad idea but it will take forever. Fairly easy to tell once you've broken through the aluminum to steel though. Yes, they're fused together, it's a perfect galvanic cell.

[BaltimoreBimmer]

You can try to thread a big bolt into it (make it self-tapping by cutting angled slots into it) and pound on it from the inside with a drift, this is how I got mine out, though they didn't break off. Use a die grinder to get whatever is left out.

Not really viable as I have a convertible. Practically no access from above. Perhaps something similar from below?

Is it a bad idea to slowly grind away the metal remains with a dremel? Is it realistic to do that and not mar the chassis? Or have they basically formed together as one now.

[varg]

You can try to thread a big bolt into it (make it self-tapping by cutting angled slots into it) and pound on it from the inside with a drift, this is how I got mine out, though they didn't break off. Use a die grinder to get whatever is left out.

[BaltimoreBimmer]

Hi. Have a convertible. Bushing broke off in my car. How the hell am I going to recover this?