ZX Front Wheel Bearing - 3 Spanners? Mon Derriére!

Chlorate · Unread post by **Chlorate** » 06 Sep 2011, 19:16

So my MOT is due to expire soon, and my nearside wheel bearing is quite noisy now.
Since I'm going to Brighton tomorrow I decided to pop the swivel hub off and bring it with me so I can swap the bearing in the Formula Student workshop, I have access to a nice floor press there.

Haynes put the job down as 3 spanners out of 5, alarm bells began ringing as the last 3 spanner job was an utter nightmare that lasted 3 days!

Anyway, jack her up remove wheel, go to remove driveshaft retaining nut - 35mm nut, globbits - biggest I have is 32 - ah well need to go to a factors anyway to get a bearing, they didn't have one... Halfrauds it is, drat 36mm impact socket will have to do.

Finally got the sod off after standing on the and of my knuckle bar - wish I had a scaffold pole or a rattle gun....

Brake caliper and disc off, more nice tight, awkward bolts.
Track rod balljoint nice and easy.

Bottom balljoint is held on with 3 nuts and bolts that have transformed over the years into RBoKs (Rusty Bits of Kack). Torx headed.....
One immediately rounded off as soon as I looked at it, out come the mole grips.

On to the strut clamping bolt, nut came off nice and easily - bolt has fused into the upright. Half an hour of soaking with penetrating fluid and heat goes by still no go...

Out comes the hammer, a bit of gentle persuasion and the car reluctantly gave up her upright.

Small puddle of gearbox oil on the floor where the inner CV came free from the gearbox

... Will need to look into that later.

Also the retaining circlip also seems to have become one with the upright, so I'm soaking that overnight to see if it'll come loose.

Hopefully I'll have the new bearing pressed in tomorrow though, then I can get along with all the other things that'll need looking at.

The perils of owning a 17 year old car eh?

Ah well she's worth it.

-Alex

Featch · Unread post by **Featch** » 06 Sep 2011, 19:55

Ah the BoL You don't need to take those three bolts out holding the lower ball joint (sometimes they're riveted!). After taking the clamp bolt out the taper separates easily if you push the bottom of the hub inwards as you tap in a joint splitter.
Make sure your driveshaft splines haven't damaged the gearbox oil seals.

Is great to get a nice quiet car back, you don't realise just how noisy bearings gradually get till you change them.

Chlorate · Unread post by **Chlorate** » 06 Sep 2011, 19:59

Given that the upper clamp bolt is still firmly seized into the upright I'd guess the bottom one is probably a similar story. But yes in hindsight it would be easier to pop it off the taper.

Live and learn.

-Alex

Featch · Unread post by **Featch** » 06 Sep 2011, 20:35

You can actually leave the strut attached and just take out the two bolts holding it at the top. Makes it a bit awkward manoeuvring the whole assembly round a press but a much quicker way I reckon.

Unread post by **CitroJim** » 06 Sep 2011, 21:10

You often need to give the retaining circlip a bit of an idea about coming out using a hammer and punch.

I get one end free by punching it into the middle of the bearing so that I can get a small pry-bar under the end and then lever it out a bit at a time. Once an end is free of the groove and away from it a small pry-bar will successfully lever it from the slot. Eventually it will give up the fight and pop out. Mind though as it my well fly. Eye protection is advised.

It will end up very mangled and unusable again but that's no worry because the new bearings should come with a new circlip too.

Chlorate · Unread post by **Chlorate** » 06 Sep 2011, 22:41

Thanks for the tip Jim, had a feeling a good hammering would help. Was worrying it was never coming out.

May try the home made mole grip circlip pliers one of the techies at uni made.

Chlorate · Unread post by **Chlorate** » 07 Sep 2011, 19:04

Well that was entertaining.

It took 2 hours of hammering, prizing, spraying and obscene language but the retaining circlip was liberated from the upright.

Only to walk over to the press and wonder how the copulating heck I'm meant to support it to press out the hub flange...
Then Kevin the technician walked in and told me it was quittin' time.

Is there a trick to it? As usual the BoL is fantastically vague about the whole thing.

Unread post by **KennyW** » 08 Sep 2011, 22:11

Chlorate,

How similar is the front wheel bearing to the Xantia model

As I have just done my front bearing on mine with relative ease

Kenny

Chlorate · Unread post by **Chlorate** » 09 Sep 2011, 00:15

I should imagine they're similar but not exactly the same. ZXs have conventional McPherson struts with coil springs and dampers as opposed to the Xantia's lovely hydropneumatic system. (Wouldn't a hydractive Volcane be nice?)

I should imagine the major difference is mine is 4 years rustier with questionable service history

addo · Unread post by **addo** » 09 Sep 2011, 01:07

Same hub is apparently in a lot of Blingos up to the middle of '98.

Chlorate · Unread post by **Chlorate** » 09 Sep 2011, 01:26

Not surprising, the Blingo is one of few cars based on the ZX platform. Makes it quite easy to source spare parts.

Isn't the C2 loosely based on the ZX as well?

Unread post by **CitroJim** » 09 Sep 2011, 06:35

Chlorate wrote: Only to walk over to the press and wonder how the copulating heck I'm meant to support it to press out the hub flange...

Yep, the BoL is its usual self...

No press is complete without a load of steel bars of various thicknesses and other odd items of circular hard material to act as mandrels that will allow the hub carrier to be packed out, be supported and sit flat on the press bed to allow the bearing to be pressed out.

Old bearings make good mandrels.

Just use the appropriate packing under the caliper flange ears and the flattish surfaces more or less opposite that is good enough to take the seven or eight tons of force needed.

It is vital the hub carrier is supported flat and at a right-angle to the press tool so that the bearing is pressed out square. If not, it can be difficult as the press will be trying to press out at an angle.

Press out the hub first using a suitable mandrel.

Then using a suitable mandrel on the inner race press the bearing out. One inner race will be left on the hub. Use a bearing puller on this to remove it.

When pressing the old bearing be ready for the whole thing going off with an almighty bang when the bearing lets go. It can be scary...

Keep an old bearing as a useful mandrel for pressing the new bearing in. Only press on the outer race of the new bearing. This is easy to set up as the face of the hub carrier is flat and can rest directly on the press plate

When pressing the hub back in, use a mandrel on the press bed to support the opposite inner race as it may pop out and thus the bearing will be ruined.

Gosh

There's more to pressing bearings than I realised until I started writing this!!!

Hope that helps a bit. Pictures are needed really...

the_weaver · Unread post by **the_weaver** » 13 Sep 2011, 21:39

Do most people hammer the swivel hub downwards, to get them off? I was wondering whether it might damage the bearing at the top of the strut? I think somebody mentioned this in a previous post. Are the top plates strong enough to take the hammering? Does anybody use a puller to get the swivel hub off?

Paul

Chlorate · Unread post by **Chlorate** » 13 Sep 2011, 23:54

Used what I had.
I did wonder whether or not it'd do some damage up there, but since it's got to support a fair bit of weight as well as bump loads etc it should be plenty strong enough. As for the bearing it's almost certainly a taper roller job. But we'll see when it's finished.

citronut · Unread post by **citronut** » 14 Sep 2011, 07:57

i always give the side of the eye on the hub/carrier that the swivel pin goes through, a couple of sharp blows with a little (honest

) hammer,

this breaks the tapper joint of the swivle pin, then just leaver the arm away,

although on the ZX like the pug 306 i normaly un/bolt the swivle mounting plate from the arm, this works 99% of the time,

as for damageing the top mount this is very unlikely as it is not directly conected to the strut leg, but via the shocker plunger and coil spring,

so there wont be any shock wave getting that far up the strut,

also you dont simply bash the arm downwards to actualy break the swivle pin joint/hold, do this as above,

regards malcolm