How to bend this back to shape?

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FinalD
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Post Wed Jul 03, 2013 7:54 am

How can I bend this back to shape? It appears to be buckled slightly and looks like it'll foul on the diff bush which will likely result in destroying the bush and potentially another diff casing.

Image


Being the diff bush mount, there isn't too much space to swing implements. I tried with a hammer but there is not enough room really. I may try with a 3/4" extension bar (using it as a pin punch) tonight but more sensible ideas would be great. I don't have a wealth of tools with me here which doesn't help.
Last edited by FinalD on Wed Jul 03, 2013 8:41 am, edited 1 time in total.
Grrrmachine
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Post Wed Jul 03, 2013 8:12 am

:? Looks alright to me. Most of those lumps and curves are there to give strength to the mount, otherwise it would bend and flop all over the place (oo-er)
FinalD
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Post Wed Jul 03, 2013 8:40 am

The bit on the left looks like it is bending in towards the bush?

Different angle:

Image

The front side of the bracket appears to be bend backwards a little on one corner (exhaust side of the photo).
scjimbo
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Post Wed Jul 03, 2013 8:47 am

FinalD wrote:The bit on the left looks like it is bending in towards the bush?

Different angle:

Image

The front side of the bracket appears to be bend backwards a little on one corner (exhaust side of the photo).
Funny enough. I'm doing this job ATM. Mine is not bent like that. I would try gently bending it back with mole grips.
FinalD
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Post Wed Jul 03, 2013 8:53 am

scjimbo wrote: Funny enough. I'm doing this job ATM. Mine is not bent like that. I would try gently bending it back with mole grips.
I think it is as a result of, or aided in this result...

Image

Image


Needless to say I'm changing the whole diff thanks to this wonderful failure. I don't have any moles, might have to see if anywhere local has them when I'm on lunch today. Really want to get the diff fitted tonight (removed the old one last night).
maggspower
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Post Wed Jul 03, 2013 9:09 am

FinalD wrote:
scjimbo wrote: Funny enough. I'm doing this job ATM. Mine is not bent like that. I would try gently bending it back with mole grips.
I think it is as a result of, or aided in this result...

Image

Image


Needless to say I'm changing the whole diff thanks to this wonderful failure. I don't have any moles, might have to see if anywhere local has them when I'm on lunch today. Really want to get the diff fitted tonight (removed the old one last night).
I think these pictures start to tell the story. Looks like the first part to fail was the diff back plate, the diff bouncing around edited the diff bush which was still attached to the car resulting in the bent mountings.

Have a look at the rear beam bushes, I would suspect these are the real cause of the issues, if they are flopping about they will stress the diff bush.

Although the mounts dont look too badly bent, you may have trouble lining everything up so it fits. However if you can get the diff in place and some bolts in it, simply doing them up may pull every thing back into line, but like i said getting all the fixings in will be the problem. A pry bar may be your friend here.

HTH, good luck.
FinalD
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Post Wed Jul 03, 2013 10:27 am

The beam bushes were replaced about 6 months ago with Lemforder ones, I'll have a look at them but I don't think they are broken already. The car was driving OK until the half shaft bolts came out and sheered.

Everything was done up properly yet the 4 diff/beam bolts were loose and all of the half shaft bolts were loose. One side being loose enough for some to come out and others to sheer off in the output flange. Luckily that happened at about 3mph and not on the motorway. Everything is going to be replaced using medium thread lock stuff to ensure this doesn't happen again but I want to bend that plate back to shape. The two plates themselves don't look like they are out of position though so lining up shouldn't be too big an issue....the issue is I'm doing it on a driveway on my own. :mad:
daimlerman
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Post Wed Jul 03, 2013 6:15 pm

At a guess,your diff has been swapped or removed at some time in the past.

It's very difficult to get the four mounting bolts tight enough whilst laid on your arse under the car,so go back every six months and check the blighters for tightness.
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Post Wed Jul 03, 2013 6:19 pm

Just put a pair of big adjustable spanners on it use one to hold the bit that's streight still and use the other to pull the bent bit back into shape.
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appletree
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Post Wed Jul 03, 2013 6:19 pm

Just put a pair of big adjustable spanners on it use one to hold the bit that's streight still and use the other to pull the bent bit back into shape.
Image

You should never underestimate the predictability of stupidity

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Speedtouch
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Post Wed Jul 03, 2013 6:37 pm

Use either a length of wood or pry bar, or Stilsons to gently bend it back. Another way would be to use a length of threaded bar with nuts on, placed through the holes and wind the nuts in or out as necessary.
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FinalD
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Post Wed Jul 03, 2013 10:06 pm

Using a variety of tools I straightened it out this evening and got on with fixing the car...

Image



Used some medium thread lock on all of the bolts (diff mounts and fresh half shaft bolts) so hopefully they won't budge, I'll be checking them every month or every few hundred miles. The checking might be a bit over the top but as it didn't even last 6 months before I'd rather not be buying a new diff every few months. :P

Filled the diff with fresh oil too so should run ok, leaving it all to settle and will drive it tomorrow.


Having looked at the old bush and the bracket, it appears that the bracket buckled into the bush, cutting it open, spraying it's innards onto the underside of the car. What I'm not sure about is if that happened before or after the casing broke or not. Either way, hopefully it is now sorted.