13 replies to this topic

[whatsoneofthese]

Hello, please can you help, I am trying to find out what the bent arm in this picture as in needs replacing. I have told it is a control arm and I have also been told it is a training arm, the garage has told me I need to get it myself.  Mini Arm.jpg   41.93K   61 downloads

[Tamworthbay]

What car is it?

[sledgehammer]

It looks like a rear trailing arm - is it on a BINI ? 

 

edit - on second look , not trailing arm

 

control arm ?

Edited by sledgehammer, 22 March 2014 - 04:42 PM.

[Tamworthbay]

It looks like a rear trailing arm - is it on a BINI ?

Guessing it must be, if you look closely I think there is 'MINI' on the shock.

OP- this forum is aimed at classic minis but some people on here have both so may be able to help. If you need an answer quick you may have more luck on one of the BMW mini forums such as mini2.com

[OJM]

Hello, please can you help, I am trying to find out what the bent arm in this picture as in needs replacing. I have told it is a control arm and I have also been told it is a training arm, the garage has told me I need to get it myself.Mini Arm.jpg

It's a rear control arm from a BMW MINI. The trailing arm is the arm that goes from front to back, and what the hub attaches to. There are 4 rear control arms in total, which attach from the centre of the rear subframe to the top and bottom of the trailing arms.

[whatsoneofthese]

Thank you so much. I thought this was the case. Really sorry to upset anybody didn't realise this was only for classic mini.

[sledgehammer]

did they have a fault on them - snapping ?

 

seem to remember some on here before with a similar fault - but snapped 

 

& to the OP - no problem with coming on here - It's just we are used to old rusty mini's

 

and may not come up with an answer as quick as a BINI  / mini 2 forum

Edited by sledgehammer, 22 March 2014 - 04:48 PM.

[Tamworthbay]

Thank you so much. I thought this was the case. Really sorry to upset anybody didn't realise this was only for classic mini.

its no problem. Glad you got an answer. Good luck,

[tiger99]

There have indeed been numerous tales of BINI rear suspension snapping, for example in one of the car mags (Car Mechanics?) about two years ago. BMW have a record of being "economical" with stress factors and running things above the fatigue threshold, indeed some of the full-size saloons were notorious for failure of the rear suspension mounts, and they built a convertible with near zero torsional stiffness. Once upon a time, LJK Setright, the technical expert (and he was very, very good) at Car magazine, sadly now deceased, wrote an article which strongly hinted at issues with wishbone thickness and such like. I think he was also having a go at Audi, and I have seen some of them with rather thin suspension arms for the size of car.

 

I don't know the full extent of the problem, but will not be buying a BINI. I know a fair number of cars that NEVER have fatigue problems, unless abused or neglected in some way or allowed to become very rusty. The only way that I know of inducing fatigue cracking (which would propagate eventually to complete failure) in a standard Mini is to mess about with the front subframe mounts. Chrome plated bumper bolts, indeed various plated bolts, have been known to fail, but that is due to an improper plating process being used, causing hydrogen embrittlement. Minis have on occasion suffered broken tie bars (actually the bolt in many cases), steering column splines and ball joints, all very serious, but you will fine that in every single case, in a standard car, incompetent maintenance was to blame. We don't know if the BINIs that failed had been badly maintained or not.

[sledgehammer]

There have indeed been numerous tales of BINI rear suspension snapping, 

 

 

I'm sure someone came on here with one

 

but can't find it on the search

 

it was a control arm snapped on an early BINI

 

I had a lancia with a rotted rear control arm (think it was approx 2mm flat bent into a channel) (approx 5 year old car)

 

Lancias were the first eco cars - they melted back into the soil , quicker than you would want them to

Edited by sledgehammer, 22 March 2014 - 06:14 PM.

[tiger99]

Yes, Lancias, and there were other cars with suspension arms that rotted. More than I can remember, actually. Maybe Hillman Imps, and a lot more recent too. That could be a factor in LJK Setright's comment about wishbone thickness.

 

Some modern cars, such as the Ford Focus, have a pressed lower arm, with box sections formed for stiffening when the two halves are spot welded together. They are supplied only with bushes and ball joints fitted (maybe just ball joints, my memory is slightly vague), and although they are fairly well painted, and those I had did not rust significantly, they are the sort of thing that could go very rusty very quickly.I think that is why the ball joints are not officially available seperately, so after a decent life the whole thing gets replaced, before corrosion weakens it. Not too bad, as decent European aftermarket suppliers make them at a good price. The only ball joints available seperately are of dubious origin, best avoided, however ball joints were supplied as genuine spares and routinely replaced on FWD Cavaliers and such like (I don't think it was because Vauxhall mechanics were more clever than Ford mechanics, just the fashion of that era), and on those the arms did go rusty. I had to clean and paint mine, before fitting new ball joints. I know of someone whose VW Polo was rotten in that area, he now has a Focus.

[OJM]

There have indeed been numerous tales of BINI rear suspension snapping, for example in one of the car mags (Car Mechanics?) about two years ago. BMW have a record of being "economical" with stress factors and running things above the fatigue threshold, indeed some of the full-size saloons were notorious for failure of the rear suspension mounts, and they built a convertible with near zero torsional stiffness. Once upon a time, LJK Setright, the technical expert (and he was very, very good) at Car magazine, sadly now deceased, wrote an article which strongly hinted at issues with wishbone thickness and such like. I think he was also having a go at Audi, and I have seen some of them with rather thin suspension arms for the size of car.
 
I don't know the full extent of the problem, but will not be buying a BINI. I know a fair number of cars that NEVER have fatigue problems, unless abused or neglected in some way or allowed to become very rusty. The only way that I know of inducing fatigue cracking (which would propagate eventually to complete failure) in a standard Mini is to mess about with the front subframe mounts. Chrome plated bumper bolts, indeed various plated bolts, have been known to fail, but that is due to an improper plating process being used, causing hydrogen embrittlement. Minis have on occasion suffered broken tie bars (actually the bolt in many cases), steering column splines and ball joints, all very serious, but you will fine that in every single case, in a standard car, incompetent maintenance was to blame. We don't know if the BINIs that failed had been badly maintained or not.

Although there are a couple of stories of snapping arms (I've never actually heard of any until Googling for them just), it will be a very small minority. The main issue with the early MINIs are the power steering pumps failing, but again, in the grand scheme of volume of sales, it's a small minority.

[tiger99]

Well, ONE snapped arm is one too many, and shows the basic inadequacy of the design.

[Captain Mainwaring]

Well, ONE snapped arm is one too many, and shows the basic inadequacy of the design.

 

 

One dodge caliper is one caliper too many.

As an aside, My newish merc snapped it's front coil springs sat on the drive.....

Have you found a car with no problems yet? if so what is it?