B20 front wheel bearings

[DavidHill]

I have found a bit of play on one of my front wheels when i jack it up and try to wobble it from the 12 to 6 o'clock positions...so I have ordered a new set of SKF front wheel bearings from Bearing Boys (for both front wheels ).  How easy are they to fit?  I assume i remove the brake drum with a puller, the bearings are held by the brake drum and I then push out each bearing from it (the inner and outer)...or is it more complex than that? - any special tools required?

[will]

Hi

When you have taken the brake drum off.
The bearings are held in place with ring nut which you will need a tool
to remome.

[DavidHill]

Many thanks Will, I assume the ring nut is castellated, so i can make up a tool from an old socket...do you know what size the ring nut is?
kind regards
David.

[ColinMarr]

You may not need any special tools. See diagram attached. Take out the split pin and undo the big nut holding the whole assembly on the stub-axle. In my experience the drum can then be pulled off by hand without any special puller. The inner bearing is held in with a castellated ring that is probably too big for any socket spanner. First, lift out the wire locking-ring (if fitted) and most likely you can loosen the big ring (in red on diagram) with a few taps with a brass drift. It needn’t be tight – the tightness will be given by the big nut. There will probably be witness-marks on the big ring where this has been done before. The bearings should then be eased out using a brass drift or a suitable socket. Happy days!  

[will]

I am told the club has the tool or your friend JK may
have one.

[DavidHill]

Many thanks Colin and Will for the advice and the very useful diagram. the brake drum came off easily with my puller and then i could drift off the large special nut at the back with a few taps of a heavy hammer and drift.  so now need to visit the "Mens Shed" I belong to in Isleworth to use the hydraulic press to take out the old bearings and put in the new ones.  The bearings don't seem to have any play in them, but hopefully they are the cause of the slight movement when i wobble the wheel.

[chriswgawne]

The play you refer to might therefore be in the sliding pillars, not the bearings David?
Chris

[DavidHill]

Hi Chris,

Yes good point, I guess I will find that out once I have changed the bearings!

[chriswgawne]

"I have found a bit of play on one of my front wheels when i jack it up and try to wobble it from the 12 to 6 o'clock positions....."

Your opening phrase set off my train of thought David. Worn wheel bearings would exhibit wear whatever position?

Chris

[DavidHill]

successfully fitted the new bearings to both sides this weekend. all went smoothly, although on the pax side the retaining nut was tight so i had to create a tool to properly engage in the castellations, rather than just use a drift.
the good news is that has fixed the wobble...so thankfully it was the wheel bearing and not the sliding pillar...

[chriswgawne]

A good result then David and nice to see you used sealed bearings. I do the same on front wheel bearings these days.
Chris

[Zetaman]

Nicely illustrated too.
I've found it can be very difficult to detect wheel bearing wear within the bearing only. 
Only a tiny bit of wear can result in the noticeable "play" you detected with the leverage of the wheel or drum. 
As Chris says it could be elsewhere but fortunately was not.  A car with kingpins may show it up there.
If I may, I shall use some of this experience in the Aurelia Workshop Manual?

Paul

[williamcorke]

Just doing this job now and am wondering if the locking nut on the left hand side drum is left hand threaded. I don't want to apply force in the wrong direction, and it is on pretty firmly (50 years of rest will do that to a nut). Can you recall from your recent experience, David?

[ColinMarr]

From my ancient experience, I am sure it's a conventional right-hand thread, Colin

[williamcorke]

Thank you Colin, you were right.

Here's my removal set-up, using the modified immersion heater spanner I made for the Aprilia. The Aurelia has the same nut.