Hi all,

I am still learning how to do the basic stuff so he goes another dumb question.





THis is my front hub with the middle dust cap removed. I want to check my bearings and possible change them. Can somebody provide an idiots guide to checking, removal and assembly. Oh and answer the below, thanks!

1) Whats this nut head type in the middle and do I need a special socket? Once I remove it, and take the caliper off, will the disc and hub just come off allowing access to the bearings?

2) How do I get the disc and hub apart? Its held on by 4 bolts but There does not seem to be enough access to get a socket on due to the shape of the back of the disc?

3) Any obvious pit falls or problems I need to consider?


Thanks again guys.

Biz

Checking for adjustment...
With the wheel on, hold the top and bottom of the wheel and feel for any play by rocking the top/bottom in and out. You should have the very sligtest bit of play. They are tapper bearings and that play is essential.
Adjusting...Remove the split pin and the lock tab/washer behind it. With pliers (socket isn't needed) tighten the nut untill all the play has gone and then back off (undo) the nut half a flat and feel for slight play. This is best felt with the wheel on. Refit the tab and fit a new split pin (or the old one if you didn't butcher it).

Checking for wear...
Once adjusted spin the wheel and listen for rumbling. Placing your hand on the upright you can often also feel the rumble of a worn bearing. No Noise and it's OK

If those two things are OK then I'd leave well alone. You'll do well to visually spot a worn bearing race (only the outer can be seen anyway) and you stand a good chance of getting grit in that'll wear it. However if you insist...

Stripping down...
Remove the caliper, split pin and ock washer. Undo the hub nut. pull out the outer bearing (put it somewhere clean). Pull off the hub/disk assembly. The disc removes with 4 bolts from the back. The inner bearing needs the seal prising out (carefull not to distort it) then the bearing comes out. Wipe out the grease from the hubs and inspect the outer races for pitting. The inner aces can't be seen as the rollers are held on them in cages. If reusing the bearings, wipe them down with clean grit free rags and repack with fresh grease. Don't overdo the grease. It requires space to do it's job Fill no more than 1/2 the space around the bearing and hub. Anymore and it won't circulate, wear prematurly and leak out. Please dont stuff the cap full of grease.
If you're fitting new bearings you need to press out the outer races from the hub. A press and the correct arbours is the adeal way. A drift and hammer will do it working bit by bit around the race. Mind your knuckles. Refitting is the reverse but be carefull not to damage the bearing surfaces or get the races "cocked-over". Warming the hub and freezing the races can help but shouldn't be needed. then refit the disc, pack with grease and refit and adjust. Cleanliness (despite all the grease) and correct adjustment will make then last.

To get the old bearing outer shells out you can struggle with a drift, however if you have a welder a little bead on weld on the running surface will cause it to contract and drop out.

If the inner race is jammed on the shaft then carefully grind a flat upon it, as you get very close to the shaft you will see the metal change colour, once you are this close you can split and remove.

These are good for 100k miles so remove, wash out with petrol and repack will probally surfice, you will need a new grease seal for the back.

Pack with LM grease.

The nut is a castle nut.

When tightening I prefer to torque to around 30lb, keep spinning the hub when doing this it should bind slightly, then back off a flat.

Regards Mark

I've never struggled to get Cortina hub bearings out yet, the race is quite an easy fit with lots of lip to knock it out from the back and sticking a welder to put a "run" on it in there is not an easy task you will more likely weld it into place. If there is no play in the bearings don't mess, you will need a new split pin. Remove the calliper, get someone to watch you who knows what they are doing if you are worried about c0cking it up.

1. The nut head is a locking cover secured by the split pin with an ordinary nut underneath

2. When the centre nut is undone remove the big keyed washer just behind it and pull the hub off. Put something on the floor to catch bits and stop them picking grit up.

3. The inner race will fall out but the outers are left in. If you fit new bearings don't use the old outers. Put the hub face down on a solid surface and tap the lip of the bearing with a punch and hammer alternating round the perimeter. Knock the new outer all the way down to the seat when refitting with a suitable size drift or socket

As Pete says they are no bother to remove but looking at the pictures it looks as if it has already been done properly.

Adjusting these adjustable taper bearings needs to be set properly to get the clearance right, nip it up too tight and the bearing will over heat and could seize solid.

As you I would advise that as you just check for excess play or noise when you spin it and only adjust if you have excess play.

If it ain't broke don't fix it

[Edited on 21/1/12 by britishtrident]

Cheers guys, great help. Ill check again tomorrow but I think the play that I felp is ment to be there after reading your responses.

Any advice on getting the 4 bolts of that hold the disk on? Do I need a thin walled socket?

To get the disc off of the hub you need to remove the caliper without disconnecting the brake hose, remove the split pin , the pressed steel locking nut , the hub nut and the hub disc assembly. Lay the hub assembly in an old wheel if you have one , then use a normal socket to remove the bolts after unlocking the lock tabs if fitted. Reassemble in reverse order, IIRC the bolts are torqued up to 65 lbs ft or 90 NMs but check. I always find the best way to adjust the hub nut is to use a socket and tighten by hand pressure alone