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Discussion Starter #1 (Edited)
The rear upper suspension arm, sometimes called the radius arm or “Link assembly - rear suspension upper” as listed in the parts catalogue, acts as a pivot and is one of the main parts of your rear suspension. At one end it is bolted into the rear subframe, at the other end it is bolted to the rear hub via the upper ball joint and between the two is where the bottom of the shock absorber is bolted to.

This part probably takes the most force when bouncing along potholes etc.

It is no surprise then that when the oil filled rubber bush at the subframe end starts to fail you will get a quite distinctive knock as you go over potholes and speed humps etc. You should get a distinct, sharp knock as the suspension is shock loaded and you will probably be able to hear which corner it is coming from.

To confirm where the knock was coming from you can jack the car up and rock the wheel. I often do this but the wheel obscures most of the things you are trying to see. Because of this I knocked up a tool to allow me to rock the hub without the wheel in place.

It is just a piece of bar with a piece cut out of the centre to clear the hub nut and 2 holes drilled in for the wheel bolts. Make sure the length of the bar is short enough to clear the wheel arch.







By rocking the hub and putting your hand on bushes and joints you should feel any excessive play.

Using this method I found the Upper arm bush to be the problem.

As this part is not able to be re bushed, you need to buy a complete arm with bush.

LH (nearside) arm is part no RGD000930 while the RH (Offside) arm is part no RGD000920

This is a fairly straightforward job if you have the right tools.

First of all jack the car up, secure on axle stands and remove the wheel.



Now give the nuts and bolts a clean and a good dose of release oil, such as PlusGas (Not WD40), as this will help you remove the parts easier.



Try not to get any oil on the brake disc, if you do then wipe off the oil with solvent such as brake cleaner.

Use your jack under the hub (NOT THE DISC) and compress the suspension just enough to not lift the car off the axle stand.



This will release some of the load off the bushes and bolts, making it easier to remove the parts. You can adjust the amount of compression to suit by raising or lowering the jack, but try not to lift the car off the axle stand.

Now remove the nut holding the bolt through the subframe bush, but leave the bolt in place for now. Both the nut and the bolt are 19mm.





Remove the bolt holding the bottom of the shock absorber to the arm using a 15mm socket. Try to use the jack to get the best position so that is not too much weight on the bolt.



Now remove the nut from the upper ball joint using a 19mm spanner.



I thought I would get away with just using the spanner, but the ball joint started turning, so I had to use a torx key to hold it steady.



The fact it turned was actually a good thing at it broke the tolerance fit on the tapered ball joint. If this doesn’t happen you will need a ball joint splitter.

Now you can withdraw the bolt from the subframe.

Spot the design error.



If the bolt goes in this way round, you have to drop the anti roll bar slightly as it is in the way.

You only need to remove the 2 x 13mm nuts holding the anti roll bar, which gives you enough room.





Now, using a screwdriver, or similar lever, move the spacer out of the way.





Which will give you enough space to manoeuvre the upper arm around the spring/shock absorber.





If you have ABS then you may need to unclip the lead from the sensor from the small fork like bracket that you can see on the last pic just below my hand. It simply pulls out of the bracket.

You may also need to remove that bracket and fit to the new arm if you have bought new.

I am replacing with one that I had on a spare subframe.

Manoeuvre the replacement arm into place. I placed the spacer in place and pushed the bolt just enough into it to hold it while I jiggled the new arm in. When you get it roughly lined up you can push the bolt further through until it emerges at the other side of the subframe bracket and put the nut on but don’t tighten it.



Place the threaded part of the top ball joint through the arm and lightly tighten the nut to hold it in place. Now use the jack to line up the arm and the bottom hole of the suspension and screw the bolt through the arm, but don’t fully tighten yet.



You then need to compress the suspension again to just before it lifts off the axle stand. This is called preload.

This is essential when tightening any suspension bushes as this is the position it will normally sit when the wheel is on the ground. If you were to tighten the bushes without compressing the suspension, when you were finished and the car was lowered onto the ground the bushes would constantly be under torsion, even at rest, and this would cause premature failure of the suspension components. It can also cause the suspension not to sit properly.

Now you need good old Mr torque wrench, or probably a couple as the torque settings are from 22Nm to 100Nm.



The sequence you tighten in is up to you, but I started with the upper ball joint which is 19mm and a torque setting of 54Nm. A new Nyloc nut should be used.



You may need to use the key and spanner until the tapered shaft starts to “bite” otherwise it will just keep turning. If you need to do this, just do it until you start feeling a bit of resistance and then finish off with the torque wrench.





Next, using a 15mm socket and a torque wrench set to 100Nm, tighten the lower shocker bolt.



And lastly, using a 19mm spanner on the bolt side to stop it turning, use a 19mm socket and a torque wrench set to 100Nm to tighten the main bolt through the subframe.



While the suspension is compressed, don’t forget to retighten the anti roll bar clamp 13mm nuts to 22Nm.



If you did unclip the ABS sensor lead from the arm earlier then remember to clip it back into position.

You can now lower the suspension (assuming the axle stand is still in place), refit the road wheel, remove the axle stand and lower the car onto the wheel.

The job is now done and just needs you to take a test drive to check everything feels OK and your knock should be gone.
 

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Discussion Starter #2
Forgot to mention. If anyone does ever find an alternative to buying the complete arm then let me know, such as a new bush to press in.

They are not available as far as I know, but someone might know different.

I know Adam looked into it too and couldn't find anything.
 

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But you can tell Clive was doing the work within a stones throw of Ashington, he even had to put locking nuts on that 2 spoke ;)
 

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Discussion Starter #6
The locking nuts are threaded closer to the end of the nut, whereas the normal ones wouldn't start on the thread.

Also, remember that I don't live that far from Bedlington. ;)
 

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I am just wondering if this may be the cause of my clunking noise. Cannot replicate the clunk whilst jacked and no obvious play anywhere else to be seen.

Great 'How To' and I may well be able to do this assuming the parts are available?
 

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mg_zt_t
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I thought this was going to be about the radius arm when i started reading.
Has anyone done a service on these? are they serviceable I.E. bushes.
 

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As an addendum to CCJ's how to, the bush is now available and can be changed rather than purchasing a new arm.

The bush part number is either a Firstline FSK7484 or Borg & Beck BSK7484.

I recently purchased the Firstline FSK7484 bush for £18.19 off fleabay :)
 

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Discussion Starter #13
As an addendum to CCJ's how to, the bush is now available and can be changed rather than purchasing a new arm.

The bush part number is either a Firstline FSK7484 or Borg & Beck BSK7484.

I recently purchased the Firstline FSK7484 bush for £18.19 off fleabay :)
Cheers Dart.
 

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As an addendum to CCJ's how to, the bush is now available and can be changed rather than purchasing a new arm.

The bush part number is either a Firstline FSK7484 or Borg & Beck BSK7484.

I recently purchased the Firstline FSK7484 bush for £18.19 off fleabay :)
Cheers Dert, that's saved me quite a few pennies as I will be doing both sides.

Couldn't find any on the bay at the moment but did find them on Amazon:

http://www.amazon.co.uk/FSK7484-FIRSTLINE-LINK-ASSEMBLY-QUALITY/dp/B00R3APVVS/ref=au_as_r?ie=UTF8&n=248877031&newVehicle=1&s=automotive&submodelId=16621
 

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Cheers Dert, that's saved me quite a few pennies as I will be doing both sides.

Couldn't find any on the bay at the moment but did find them on Amazon:

http://www.amazon.co.uk/FSK7484-FIRSTLINE-LINK-ASSEMBLY-QUALITY/dp/B00R3APVVS/ref=au_as_r?ie=UTF8&n=248877031&newVehicle=1&s=automotive&submodelId=16621

Not quite as cheap I got mine for but at only 14p more expensive that's still a good price :)

For benefit of others if looking on fleabay just search FSK7484 it will bring them up, just 1 left at the price I paid, others are same price as Amazon or higher :)
 

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Hi everybody! Great howto, usefull and well explained, thank you CJJ and everybody else has contributed! Now, I plan to do this job, but I would like to have some further clarification about doing and undoing the ball joint. I never had to do whit that staff and I wouldn't like damage something. Particularly, I didn't understand the part about the tolerance fit. Also, I thought if you use the torque wrench on the 19mm nut, as CJJ does at the end of the rebuild process, the whole ball joint should turn around... Maybe I'm wrong. Also, I'm not english so I might have misunderstood something.
Cheers everybody and thanks in advance!!!

Marco (from Italy)
 

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Hello Marco,
I'm not sure what CJJ meant by 'tolerance fit'. Tolerances only really matter if the ball joint shaft has a parallel (constant diameter) shaft. Tapered shafts will always make a good tight fit into the hole they are in if the hole is also tapered and the shaft is pushed in far enough. Perhaps he meant to say 'taper fit' or 'interference fit' (same thing in this case - the taper shaft an hole are in intimate contact)..
My experience with ball joints is that they never want to come apart. There are two types of tool to split the balljoint away from the hole in which it fits - one looks a bit like a wedge-shaped fork with two prongs (you hammer it into the gap between the balljoint rubber and the arm it fits into to prise them apart), the other type has two arms/levers on a pivot/hinge and a jackscrew which you turn. It levers the balljoint out of the hole.
As for the final step of torquing the new balljoint, CJJ does say to tighten the new nut down onto the balljoint shaft a little bit to start, using a spanner and a torx allen key. What this does is (the nut) pulls the tapered balljoint shaft into the tapered hole in the arm, until they lock together. At that point the balljoint shaft will be stopped from rotating (when torqueing the nut) by friction within the hole in the arm in which it is now fitted. If you're not familiar with taper joints/fits, they are used a lot for the shafts of large industrial drills for example - the shaft of the drill has a very slight taper on its diameter, and when it is pushed firmly into the drill chuck hole with the same angle of taper, the two lock together very effectively with no other fixing needed. It's just held in with friction. In fact it takes a special tool and a hammer to take the drill out of the taper hole in the drill chuck when you want to change drills!
 

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Thank you very much nocturneblue! Now it's all much clearer. Anyway, work is in progress; I have set the arm free except for the ball joint connection and I already bought the tool (the second you described) that is supposed to be delivered monday or tuesday. Is the process of removing/refitting the bush somewhat complicated? The question is to buy the whole arm equipped with the bush or only the bush.

Cheers and thank you again!
Marco
 

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Hello Marco,
I have not replaced this particular bush so cannot speak from experience. I have worked on replacing the bush for the lower engine tie bar though (when I polybushed the tie bar then replaced the polyurethane bushes with rubber once again). The problem is that the rubber bush has a metal sleeve which is an interference fit in the arm. To remove it you must press the bush out by pressing on the outer metal sleeve with something suitable (a suitable diameter metal tube accompanied by either an hydraulic press or with a big hammer ;0) This may require a LOT of force. Or maybe you can cut through the outer metal sleeve with a hacksaw, though the rubber, from inside out, but the that looks difficult on this particular bush as it's not large enough to get a saw inside I think. Then to get the new bush back in you need to adopt similar pressing techniques.
When I replaced the bush on the lower engine tie-bar I did so using a suitable diameter metal tube and a heavy hammer but found it hard to get the bush fully back into the arm. The best tip I can give you if trying this without an hydraulic press is to cool the bush in a freezer for a few hours and heat the arm into which the bush goes - then hammer the bush in very quickly, before the arm can cool and the outer sleeve of the bush can warm up ( things expand when hot and contract when cool so theoretically it is easier to get the bush into the arm if the arm is hot and the sleeve is cold). Easier said than done though. If you get it wrong, you're stuck and will need to get a garage to finish pressing it in for you. There may be MGTF owners who have done this on other owner websites - the T-bar etc.
 

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I'll wait to have the part in my hand then I will decide what to do. Maybe using a vise could help. And if I fail I can always give up and buy a brand new arm (a couple, since I plan to do the job on both sides).

Next week we'll know!
Thank you and good night!
Marco
 
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