Rear arms
 

Hi everyone,
Yesterday I took my car at mgr expert and unfortunately we discovered that rear arms are about to go, I knew they would need doing at some point I just did not expect it that soon amazing what one winter can do. And the news got worse as the top bolt on the drivers side which seemed to be the one worst one was ciesed on so it seems like I'm going to need a trailing arm the rear disc back plate and a hand brake cable on top so the expense is going to be great my problem is that I can't really afford or justify such an expense with this coronavirus craze going on in the world at the moment so I'm baffled as how to take things forward. I don't think that this is something I can DIY tools or ability wise. If you any suggestions or experience with this issue please let me known !

Hello Thanos,
Get onto the DGMRS website (see traders on this forum). Matt and company can sort out all your parts needs. Rgds M.

Which trailing arm do you need - left or right?

which bolt is seized? The one that goes through number 3 here
https://rimmerbros.com/Item--i-GRID001553

cant the ends of the bolt be cut away, arm removed and then the bolt hammered out? You may need a new bush but surly not a trailing arm and back plate.

macafee2

It's the right

I think its number 3 my MGR expert said the way the trailing arm is shaped makes it impossible to press in a new bush in the press so it's easier to swap the trailing arm

You could either buy a new RH arm for £190 ish - or refurb the existing arm by fitting a new bush.

I can't see why he says bush #3 can't be changed because there's nothing blocking access to it. Bush #2 is trickier because of the curve of the arm, but it can still be changed with MGR tools. RAVE (page 64-10 Repairs) shows them being used - one to push the old bush out and another to press the new bush in. There are six tool ID numbers.

https://www.the75andztclub.co.uk/for...cf509350a0.jpg


Your man is right though - it's easier to fit a new arm (but not necessarily cheaper).

Just to clarify the bit in blue below - are you 100% sure he's not talking about the upper arm to subframe bolt (#3 here)? That's the one that usually causes trouble - not the trailing arm bolt(s).

Sorry yeah that's the bolt I meant not the trailing arm one.

ok so does that mean you don't need a trailing arm and back plate, good news I hope:)
However I'm now unsure of the issue. I know the bolts can seize in the captive nut causing it to become free
but from what I've read that can be sorted but the sub frame needs removing.
While they are under the car check these https://rimmerbros.com/Item--i-GRID001554 item 6, they are no longer available from rimmers so if starting to rust get them cleaned and painted.
I've changed these on both my cars
part number KHV100020

macafee2

I'm probably missing something here I think anyway If I'm being honest I can't see an easy way out of this and to put this right it going to cost pretty much the value of the car so is It worth it that's my concern and as I mentioned before I can't really justify an expense like that with what's going on in the world at the moment so may have to stay without a car for a little while till things calm down it doesn't feel safe driving it like this I'm surprised it did not come up on the mot but again they didn't look nowhere near as bad a few months ago

yes those upper arms are duff and your right not to be driving around.

How much have you been quoted and what does the quote include?
In the left had picture one of the "washers" can be seen at the top, get all 4 checked

macafee2

Left arm, right arm trailing arm disc back plate hand brake cable I usually shop around for the parts myself he fits them so all in I think in the £700 area and I only scrapped my other 75 which had arms and everything in perfect condition 2 days before discovering this massive face palm

why do you need a trailing arm?

£700, ouch

macafee2

For comparison , I recently had both upper arms replaced at a local respected garage ; I supplied the parts and they charged me £160 for labour . They said the job was problem -free ! They had the car for about 5 hrs and a courtesy car was included in the price . I got the parts from Rimmers , but I believe DMGRS are currently supplying a pair for about £160 .

I fitted one upper arm at the side of the road last week for a local member.

The job was made trickier as he had attempted to undo the pivot bolt with a bi-hex socket and knurdled the head.

Removal of the old arm, and fitting of the new one took me around an hour and a half, on my back with the car on axle stands.

If we break down an estimated £700 bill, a pair of arms are £240 (retail), and on a ramp the job will take no more than two hours assuming the rose joints are OK, and another hour if both rose joints need to be replaced.

So a maximum of 3 hours labour, and a maximum of £300 in parts........err I would look elsewhere if I were you ;)

And no you don't need trailing arms either :cool:

Brian :D

Not an expert then, if you are talking about the rose joint on the outboard side of the upper rear arm, a competent person with the correct tools car change this part in about.........well the last one I did took 15 minutes to remove and refit the new joint ;)

Brian :D

Sorry for all the confusion after having a good look around its bolt number 4 that's sieced on and that's why I was told I'll need the trailing arm

Chop the head off it and drive it out with a drift.

see posts 4 and 20, "same" advice
In fact you may not need to remove the head, drift the bolt out with nut still on for as far as you can then remove nut and drift/hammer the bolt all the way out.

macafee2

You will not be able to drift the bolt out, so in light of that here is the definitive answer to the problem ;)

Chop off the bolt, remove the upper arm, then belt the middle out of the bush with a mash hammer, it will not resist I promise

Of course you will have bought your new rose joint bush, if not.... phew you won't need to break the bank, as the identical part is fitted to E46 BMW rear suspension, so treat yourself.........LINK

Now comes the interesting part, without further dismantling of the rear suspension, buy yourself one of these.......LINK, I'm sure I don't need to elaborate on how this is used, or do I?

I've got a Vectra B rose joint tool, for which I machined up a deeper mandrel to accommodate the longer 75 bush, however I would have probably bought the tool in the link if it had been available at the time.

So, no need to start dismantling any further, if you wanted to be creative, after bopping the middle out of the bush, you could hacksaw through the outer part left in the trailing arm, then simply drift it out, remove the boot from the new bush, then after cleaning out the hole in the trailing arm, pull it into place using threaded bar, and a suitable size socket, or even the old bush housing with a big washer.

It's up to you, with the tool I use, the whole operation will take you less than ten minutes, I'm sure improvisation may take longer, but the end result is a whole lot cheaper and more satisfying than paying for an unnecessary part.

Brian :D
____________

Hi Brian.
Hope you & your are keep well & safe, even better to see you are posting fantastic information once again than you. :bowdown:

Great info here thanks a lot ! I'll speak with my MGR expert about this approach see what he says (I'm not really equipped for this job to do it at home)

He'll still need to get the upper arm to subframe bolts out without the causing the captive nuts to start spinning, which they're likely to do if the bolts are very rusty.

The RH upper arm captive nut on mine started to spin because I didn't soak the protruding tip of the bolt with penetrating oil before I started. I should have lowered the subframe first (to gain access).

Here are the upper arm captive nuts - they're not visible from any other angle. If they start to spin the bolts won't come out and you'll have to take the subframe off.

https://www.the75andztclub.co.uk/for...a47fa2ecca.jpg

The lower arm captive nuts can be seen from underneath - access is easy.

https://www.the75andztclub.co.uk/for...a49e3a49ab.jpg

Lower arm pair again - closer (split) view

https://www.the75andztclub.co.uk/for...a4d4f6b200.jpg

More access through here (arrows)

https://www.the75andztclub.co.uk/for...a500d78695.jpg

For reference, here's a full view of top side (not visible from under the car).

https://www.the75andztclub.co.uk/for...df7618730d.jpg

And this is the bottom side.

https://www.the75andztclub.co.uk/for...df717e3f66.jpg

Here's the tip of the RH upper arm bolt protruding from the captive nut (on a new subframe). De-rusting the tip and bombarding it with penetrating oil is the key.

https://www.the75andztclub.co.uk/for...dfcf245104.jpg

....... :wot:

I found that you can spray plus gas through the plastic straw attachment, right onto the protruding bolt threads via the gap shown in the pic to the left and underneath the arrow, over the weld. Moving the can and straw in and out as you spray creates a wide arc of lubricant/freeing liquid.

True, but you can't get a wire brush* onto the thread. It really needs both - i.e. wire brushing, then repeated bombardment with PlusGas.

* Mini wire brush with steel bristles.

I've done fifteen pairs of arms now and never needed to resort to subframe removal.

The trick is tighten first, before attempting to slacken, which breaks the rust hold without stressing the cage securing the captive nut, and as soon as the bolt starts moving, switch immediately to 3/8" drive sockets, which allows much greater "feel" and if the bolt starts to tighten, reverse the ratchet and tighten the bolt once more.

Lots of plusgas through the hole in the bottom of the box section of the subframe, and I tend to use a mini maglite, an incandescent one not an LED so you can spray the penetrant directly onto the end of the bolt.

If the bolt is attempted to be wound straight out, it will almost certainly end badly, working this bolt patiently will pay off in as much as the resultant work of subframe removal can be avoided completely ;)

Brian :D

Brian - once the new bolt is back in*, what do you think of spraying the protruding thread with Dynax S50?

(*After it's torqued up)

I'd say it's an excellent idea Simon, I always spray cavity wax in when I do the job to prevent the exposed end of the bolt corroding ;)

Brian :D

I think I may go a completely different route I'm trying to see if I can source a subframe with everything bolt on to it from Greece they tend to fairly rust free from there and just swap the whole lot instead is there any difference between models I know that non v6 post project drive cars had the rear anti roll bar deleted but this shouldn't matter right ?

https://i.imgur.com/jjuLwGm.jpg

I reckon you could do that, however a little expensive perhaps, and the logistics of having it shipped may prove problematic at the moment.

The job itself is fairly straightforward, and only requires a limited amount of tools to carry out the work.

Who are you using in Coventry?, perhaps Lates may be a better bet perhaps?

Drop him a line HERE

Brian :D

The parts I would most likely get for free ( family friend owns a rover shop there ) they don't really need those parts there as they almost never rot is just the logistics of getting them here which is the issue. I use gavin mg rover repair here for almost 2 years now and I have nothing but good things to say about him. Thanks for the recommendation though!