Rear Subframe Problem - Radius arm bracket bolts sheared
Turbo Mini Forums

Hi guys,

Had a bit of trouble a few months back when I removed my radius arm brackets and 4 out of the 8 bolts sheared and left the studs in the thread. I have spent so much time trying to extract them etc with no luck and am getting fed up now...running out of ideas. Like I said it's been months since I removed it to give it a clean up and I wish I'd never bloody removed it now. I just want to get it back on it's wheels now after being on axle stands for so long!!!!

I'm contemplating a new subframe but they are so bloody expense. Does anyone have any experience with the non-genuine frames and their quality? My car is only 1995 and I know people with older minis with subframes in good nick, can't believe such a new model has a shitty subframe.

Does anyone have any recommendations for fixing the problem or just general suggestions?

Thanks

Mike

Lots of heat on the subframe and a stud extractor maybe, lots of weld on what's left of the bolt and weld that to a nut, drill and tap the stud and tighten it into the hole instead of removing, Or just drill the thing out completely and retap to something bigger or fit a helicoil/other insert. Depending on what you have to hand and how creative you're willing to get, the possibilities are pretty endless! Good luck for the removal!

When I've got sheared bolts I build a chunk of weld with a MIG then grip onto it with a pair of mole grips and rotate it out.


I've never had a problem fitting non-genuine subframes or any concerns about the quality. I've fitted three within recent memory and also have one on my project car

The only thing I would recommend is to give them a really good coating of chassis black or similar to protect them in the future.

All of the frames where bought from my local All Parts.

mig is a good bet if you have enough to weld onto,

the head does somthing to the rust so they'll come undone.


also another thing Ive done is welded a nut to a washer, and drilled the old thread out big enough to let the nut in and weld it in place.

Thanks a lot for the replies, very helpful!

Well, 3 are studs left in the thread....and 1 is an attempt of drilling out the stud and nut big enough to get a new nut in there and weld it up - I'm not sure i trust the strength of it though!

I have tried with 2 different stud extractor kits to remove the studs and the first stud extractor sheared itself when trying to unwind the stud (some stud extractor!!!!) The second heavy duty stud extractor kit, the threads on the extractor just disintegrated as I tried to extract the stud - couldn't believe two different stud extractors couldn't remove the buggars or weere at least robust enough to give it a good go!!!

That mig option I haven't tried, I will give that a go in the next few hours and report back.

As for the captive nut I need to replace completely, whats the strongest and best way to go about it? I think I get your method Joe C, but is the washer then not prominent on the face of the subframe, sitting above the surface?

Cheers

Mike

Edited by Mowen123 on 2nd Feb, 2014.

drill the hole so the washer will just fit through the hole, screw a long bolt in so you can hold it in position to tack it, then seam round it and buzz the weld flat.

use a thick washer though,

When welding with the mig, crank the power up and try to get the whole pool a nice cherry red, you'll have a better bet then, just try not to weld the stud to the captive nut lol.

Open it up from the rear with a grinder.
Grind or smash out the old welded nuts.
And weld in new ones.

If grinded perfect..the piece that came out..can be welded back in..

Offcourse only possible with the frame removed from the car.

I did 2 subframes like that a few months ago.I replaced the nuts for fine thread m8.

Non-genuine subframes are fine to fit.. often no problems. Paint is poor as mentioned above.
But some frames do not line up as nice as an Original.
So the car's wheels are out of line..as can be seen when you drive behind.
In dutch we say..it hit's the road like a crab..
And if you've ever seen a crab walking in a straight line you know what i mean..-)

It's a little car .... eating big money

on the subject of migging, Ive found tig is really good for this as you can heat the stud withou addin more material,

I'd probably start with a small pilot hole and work your way through the drill bit sizes, I think as long as the washer is as thick or thicker than the subframe and you get really good weld penetration it should be okay once ground back flat as Joe suggested.

try twatting the sticking out stud ( if it is sticking out) you might pop the welds off the captive nut so it leaves a hole to start with,

otherwise knock it back flush with a grinder, centre punch it and pilot drill with 2mm then work up, go gently woth the pilot drill, if you break that off you wont be drilling it out!

Worked a treat, got one of them done. Just 2 left to do now.

Persistence usually pays off !

You're right, all done now! I had given up on that subframe, after my many previous attempts to repair it...I'm glad some of you had some fresh and helpful ideas.....saved me a lot of money in the end repairing that one!

Glad you got it sorted bud!