XM lower front swinging arm bushes

[noz]

After having gone through yet another pair of tyres on the front of the 2.5TD it was time to do some further investigation.

Last time the fault was easy to diagnose, both front strut tops were completely shot. I replaced them and thought that the problem had gone away. Certainly the tyres took longer to wear but wear they did.

On the nearside tyre there was still 1-2mm of tread left on the outside edge but the inside edge has worn down to the fabric.

Jacked the car up and tried to rock the wheel up and down first. There was some movement but not masses. Then I rocked the wheel horizontaly from side to side. There was loads of movement. Crawled under the car and got someone else to rock the wheel. All the movement was coming from the larger of the two bushes on the lower swinging arm.

Has anyone replaced these before? Am I going to need the services of a hydraulic press? What sort of job is it?

any help appreciated as usual.

cheers

noz

[rosspa]

The following is an extract from my diary (2.1 TD XM):
Ran front of car up ramps, and as I intended to disconnect the o/s drive shaft, I slackened the drive shaft nut first and then jacked and put on axle-stands. Removed both front wheels. Replaced n/s track-rod end and disconnected bottom ball joint. This was very difficult and required considerable heat and hitting with a lump hammer in conjunction with a ball-joint separator, but it finally gave up and the removal of the bottom wishbone was then straightforward. The bush replacement was quite difficult. The pair of bushes were removed by cold chisel and lump hammer, knocking the right-angle flanges outwards all around until they were almost parallel with the body. At this point, they would start moving. The single rear bush required the outer cylinder and rubber part removing, leaving the bush inner cylinder. This was then hack-sawed almost through longitudinally, being careful not to mark the wishbone shaft. Finally, a chisel was applied to the cut to split the remains of the bush which was then easily drifted off. This slit cylinder was then used to drift the replacement bush into position. A large vice was used to squeeze the first of the bush pair into the other end of the wishbone. The second bush of the pair was also squeezed into position using the vice and a suitable (similar in diameter to diameter of rubber portion of bush) large socket as a spacer.
The wishbone was then refitted to the car and finally tightened up when the suspension was in the normal position.
The o/s wishbone was straight forward as far as bush replacement went, but after getting a pleasant surprise at how easily the bottom ball joint separated, one of the rear bolts holding the wishbone bush clamp was seized solid. After applying oxy-acetylene, it finally came out, covered in white corrosion from the lower wishbone clamp half. This cast aluminium component came away in two parts, extensively corroded, it should have remained in position. The rest of it was left in position, still holding the anti-roll bar bush. Since replacing it meant dropping the rear of the sub-frame, I carried out a repair using plastic metal and used the same to reattach it to the remaining portion still on the sub-frame. I bolted it in position using the new wishbone bush to mould the plastic metal to the correct shape while it set.
I also replaced the outer drive shaft boot taking the opportunity to clean and repack the CV joint. I then refitted the drive shaft to the hub and strapped the boot in position. Finally, I refitted the hub lower ball joint to the wishbone and refitted the wheels, jacked of the axle stands and left overnight for my repair to cure.

As a post script to the above, the car drove much better and quieter after the above repair and I went on to do a further 40,000 with no problems. I would not, however recomend the plastic metal repair. In this case I had no option, and I reasoned that even if the repair failed, THe wishbone would still be held safely in position.

[noz]

Thanks Rosspa,

There's been a development in the sense that I've tried to start the job. The lower ball joint wasn't a problem since I've got a proper scissor-type splitter which never fails to do the job. I also managed to remove the bolt fornthe front bush. However, when I tried to remove one of the three mounting bolts for the rear bush it sheared next to the bolt head.

The problem I have now is that the remaining part oof the bolt left attached to the alloy casting is fouled in the other part of the casting and I can't remove it. I would need to lift the whole assembly clear of the chassis but it's proximity to the bulkhead prevents this.

One of the bolts must screw into a steel keeper and I've got this to move no problem. However the third bolt is also into the alloy casting and I fear that it will shear also. If both have sheared I'll be alble to hacksaw through the bolt nearest the roadwheel no problem but I fear not being able to access the rear bolt.

If I can get the whole assembly out I can easily repair it on the bench with some OxyCetalene but if I cant even get it off the car then I'm snookered.

Why do we do it to ourselves?...................

cheers

noz :cry:

[rosspa]

Noz,
I sympathise with you entirely, It sounds like you are experiencing exactly the same problems that I had, with my car it was the o/s was the problem, extensive corrosion of the aluminium lower half clamp. Although the steel bolts are a clearance fit, the swollen aluminium oxide, causes them to be held in a vice like grip. It is all to easy to shear off the heads. Luckily, in my case, the use of oxy-acetaline and copious plus-gas eventually got them moving. I had to heat the bolt heads to red! Doing this eventually breaks the corrosions grip. In my case, however, the aluminium piece broke at the front outer bolt position, and as the bolt that had sheared, I could remove the top steel clamp and remove the remains of the bolt from the steel half. I couldn't, however remove the remains of the aluminium part. without lowering the sub frame rear. My solution was to clean the remaining parts of the aluminium part and repair, with JB Weld epoxy 'liquid metal' the part in situ. I then re-assembled the wishbone, complete with new bushes, before the epoxy had 'gone off'. I reasoned that as the whole assembly was in effect clamped anyway, that there shouldn't be a problem, even if the epoxy failed.
Anyway, good luck with your problem and I hope that this has been of help. The lesson is to check your rear sub frame mounts (that all bolts can turn OK- carefully!) and to protect the area with waxoyl or similar, to avoid the corrosion problems.
Cheers- Paul

[noz]

Paul,

I sheared off the bolt closest to the wheel first. So I decided to take it easier with the inboard one since getting at it after shearing would be immensely difficult. I tried all sorts of releasing fluid to no avail. Having got it off now, I understand why. The corrosion happens in two locations, between the steel bolt and the alloy casting and between the steel bolt and the steel cap. The penetrating fluid just cant get in to do it's job.

Heat is my favourite trick for anything rusty. However, there are a few flammable things very close to the point requiring the heat. I made up some heat shielding from some aluminium sheeting and got the OxyAcetelyne out. I heated the bolt and the steel casting from the top. I managed to set fire to the protective plastic bag on the end of the steering rack and the small hydraulic return tube just below. The bag's no loss but I'll have to joint the return tube otherwise I'll have LHM all over the drive (again).

After heating, the bolt came out no problem. This probably means, in my case at least, the worst of the two corrosion points was the steel bolt to steel cap joint. So now I have one bolt fully removed as normal and one bolt left in place minus the head. No problem I thought, just lift the cap up a little and hacksaw through the rogue bolt in place. No such luck, the cap wouldn't budge. I hit it with a cold chisel for half an hour but only succeeded in splitting the alloy casting. It seemed to split in a different place to yours Paul. Mine split about half way between the two bolts. Even then I couldn't get it off the car. The length of the sheared bolt left in the casting fouled the chassis preventing removal. I lifted the whole assembly enough to get a hacksaw blade underneath and shortened the bolt enough to get the whole thing off the car.

Even in the vice, the bolt proved stubborn to remove. I heated the steel cap end first and managed to get it off the bolt by rotating the whole thing. Now I was left with part of the sheared bolt in the alloy casting with the threaded part sticking out where the steel cap used to be. I heated the bolt from both ends until cherry red but still had to hammer the bolt loose. I had to drive it all the way with a punch. The corrosion had a really good grip of the bolt, no wonder the head sheared off.

Replacing the bearings was a doddle. I used a chisel to remove both parts at the front end of the arm and a hacksaw to remove the rear bush. I pressed in both front bushes with the vice and tapped onthe rear bush with a lead mallet till it measured 330mm.

I haven't put the arm back on the car yet, I was waiting for a break in the weather. (Doing all this outside because the garage is full of CX at the moment.) I need to find a joint for the return tube and a replacement M10 bolt.

That's tomorrows job. Although the worst is definitely over. I agree with the philosophy of the broken casting. It's all clamped in place by the cap and will do cemented into place.

I'll give you an update when I'm finished.

Cheers

noz 8)

Hi Noz,

Sorry to have to send a private message on the public board; I know it's bad form etc but despite going in through Internet Explorer, I cannot get the blasted security system to accept my name and password. This is a known problem for AOL users................. I can post publicly, but not privately. Tell me, does anyone know why a general interest board like this needs online security? Anyway, if you remember I have a rather sorry BX TZD. Taxed and with MOT it just needs a repair/replaced diesel pump to make it mobile. A friend of mine said he's have it, but last I heard he was about to go off to France on short notice on an indefinate visit, so unless he picks it up by the end of this week it's yours if you want it. It's free, but you'll either have to come and collect it or pay delivery cost. All electrics work (including drivers electric door mirror), it had a new timing belt fitted last year and a new clutch the year before.

Have fun,

Jim.

Jim,

Sorry about the logging in bit, I'm not entirely convinced it's an AOL problem since there's more than you with the problem. Do you have a firewall? If so check the log just after you've tried to log on to the forum and check what it says. I use Norton System Works with an integral firewall and there are many reasons why it stops the logging on process. How high is your security settings especially for cookies? Try temporarily switching off your security and try to log on (remembering to switch it back on when you're finished !).

What year is the BX. I might be interested. What sort of timescale do you need it removed by? I'm stuck for the next couple of weeks.

cheers

noz 8)

[noz]

oops,

where's that darned cookie when you need it?

noz