Changing a set of 'sealed for life' bearings

Trailer Guy · 14 March 2012, 20:20

I did a thread on how to change a set of taper roller bearings recently and Nick Hearne asked if I could do one the next time I changed a set of 'sealed for life' bearings, so here you go

I recently did a service and bearing change for Steve Hall (member on here) and he generously agreed to let me post some pics up for everyone's benefit.

Anyway, 'sealed for life' (SFL) bearings are a bit of a misnomer, as they're certainly sealed, but not to the exclusion of water ingress. They're fantastic bits of kit for cars and caravans, but not so good for trailers that get dropped in the drink on a regular basis. In my experience, even the ones labelled and advertised as 'waterproof' generaly aren't.

So if you run SFL bearings it's still advisable to check them on a regular basis - listen for rumbling, check for overheating etc. One of the down sides of SFL bearings is that you can't easily service them, i.e. strip them, clean them, repack with grease and reinstall them. If they're gone, or going, it's best just to replace them....

So remove the drum; usually a large hub nut, with no split pin. They're generally done up to around 280Nm, so make sure you do some press ups in the week leading up to it. Then remove the rear circlip (a pair of ratcheting circlip pliers are useful):

Then flip the drum over and press the bearing out from the front, pressing towards the rear / back of the drum. Place a large socket between the press and the bearing face, so it distributes the force more evenly:

Then you'll have the bearing out (on the left) and the new one to go back in (one in the oiled, protective wrap on the right):

Then just do the reverse to install the new ones. Easy as that! With the one shot nuts (no split pin) make sure you replace it too when you replace the bearings.

If you haven't got a press lurking about then you can (though it's not pretty or quiet) replace the bearings by giving the socket, you've put on top of the bearing, a ruddy good thump with a large hammer. It's not ideal, as it's possible to damage the bearing, but if you're in a pinch it may be the only option.

Nick Hearne · 15 March 2012, 13:13

Thanks for that, I have given up on restoring mine & weighting for a new axle to arrive!

Smithyyy · 15 March 2012, 23:30

Just in case anyone finds it useful to know, one of these dealt very happily with getting the SFL bearings smoothly out of my hubs - not too portable, but nice to have the capability to change the bearings myself at home anyway (and one of those "sure it'll come in handy for other jobs" buys... :-) )

6 Ton Industrial Hydraulic Workshop Garage Shop Press | eBay

(I found one slightly cheaper, at £60)

Then a 40" breaker bar from elsewhere on ebay shifted the hub nut nicely as wel...

Boats&Outboards · 16 March 2012, 00:04

I've just wasted £350 on a 20T press after being told that's what I'd need

Still it will come in handy when I need to have somebody's balls on a platter

Peter @ Boatsandoutboards4sale ~ askboatsandoutboards4sale@sky.com ~ 07930 421007

Downhilldai · 16 March 2012, 11:07

Quote:

Originally Posted by Smithyyy

Then a 40" breaker bar from elsewhere on ebay shifted the hub nut nicely as wel...

Yep, I recommend using a 3/4" drive power bar & socket for this job, as a lot of 1/2" ones simply aren't up to the job.

Smithyyy · 16 March 2012, 19:31

Sorry Peter! But then I'd noticed Trailer Guy seems to use a hand-operated version, which is presumably cheaper and more portable than my hydraulic jobbie so I'd had similar teeth gnashing ... on the other hand one day there'll be some completely rusted in old mother of a bearing for which a 20tonner will be just the job!

Agree with downhilldai a 3/4" drive is best, I'm using a 3/4 - 1/2" stepdown as I already had the 1/2" socket in the hubnut size and all my other sockets are 1/2" or less - it's worked so far but the loads involved are impressive, I should have just got a 3/4" socket instead

Of course the final pieces of kit you need for a proper job are a meaty pair on circlip pliers - as you can see above it's a hefty old clip even if not rusted in - and a torque wrench able to handle the 214Nm or whatever it was to put the new hub nut on (or its a case of working out what weight you need standing on the end of that breaker bar but I suspect getting it right is probably quite important). Clearly you end up spending more than it would cost to pay someone to do it for you - but you get (a) satisfaction doing it yourself (b) tell yourself you make it back in the long run, (c) [the real reason] lots of shiny new and meaty tools to play with and satisfy your "if you can't fix it get a bigger spanner" instincts!

Or you ring Trailer Guy who by all reports does a great job and who as we see on here is helpfulness itself and ask him to do it - and hope he doesn't mind this detour into DIY land... assume if he did he wouldn't have posted the description anyway - thanks TG!

Boats&Outboards · 16 March 2012, 19:36

Never mind. It's not just used for trailer bearings anyhow so it's not wasted more invested

Peter @ Boatsandoutboards4sale ~ askboatsandoutboards4sale@sky.com ~ 07930 421007

Trailer Guy · 05 April 2012, 23:41

Quote:

Originally Posted by Smithyyy

Or you ring Trailer Guy who by all reports does a great job and who as we see on here is helpfulness itself and ask him to do it - and hope he doesn't mind this detour into DIY land... assume if he did he wouldn't have posted the description anyway - thanks TG!

Hi Smithyyy, that's very generous of you. Of course I don't mind the detour! I'm a firm believer that forums are here to help like minded fools out and if I can put a bit of information up here that stops just one poor bugger being stuck at the side of the road for four hours (or worse) then my time's been well spent.

Anyway, as a nicely timed example, I did a service on a chaps' trailer the other day. His brakes and bearings, on both sides, were pretty well seized on and I had to use one of the hub pullers to get them off (on the left of the first pic). As I did the bearing collapsed, leaving the internal race stuck on the shaft. But not for long obviously

I've also posted up a pic of my 3/4" torque wrench (rated to 395Nm) to give you an idea of the equipment you should think about if you're doing this on a regular basis. Worryingly, I know a few trailer places that don't have them, so Lord knows how they torque the hub nuts up correctly.

Anyhow, feast your eyes!...

Drum etc (with part of the shoe inside it)

rollers that had fallen out of the bearing:

Race stuck on shaft:

3/4" torque wrench (btw, that's a 3/8" ratchet next to it, for size comparison):

robbo1 · 20 April 2012, 20:19

Hi Trailer guy.
have you ever changed a set of sealed for life bearings on a Brenderup unbraked boat trailer? It's not very obvious how to remove the hubs.

Trailer Guy · 20 April 2012, 20:54

I'd have thought so

From memory it's just a case of taking the dust cap off and undoing the nut, but it's possible you have something a tad more interesting.

Pop a pic up, once you've removed the dust cap and I should be able to point you in the right direction.

Rokraider · 20 November 2012, 15:42

TG, in your view, what is the best hub bearing / brake setup you have come across that will survive dunking in salt water on a regular basis? I am going to build a new trailer for the Pac 22 and have been looking through the 4x4 stuff to see if anything could be adapted from that area, but have not really found anything suitable yet.

Trailer Guy · 20 November 2012, 21:30

If it was me, personally building something from scratch that I was going to keep for a long time, then I'd invest a bit of money and time. Disc brakes, stainless running gear etc.

However, going for 'off the shelf' stuff, in my humble opinion, Alko are still better than Knott. Others may disagree, but my points are:

There's no carrier shoe, so less to rust and seize.

They were the first to come out with stainless cables and they've now stepped it up again, by coating the stainless inner with plastic. Also the fixings are stainless now too - the nuts etc. These are all moves in the right direction.

You could also have the shoe linings brass riveted to the shoes, helping to stop them delaminate.

If you don't like the idea of the 'sealed for life' bearing units then you can have axles made with taper roller bearings, that are serviceable, but run on Alko brakes. Indespension do this.

Does any of that help?!

mick · 20 November 2012, 21:54

Quote:

Originally Posted by Rokraider

TG, in your view, what is the best hub bearing / brake setup you have come across that will survive dunking in salt water on a regular basis? I am going to build a new trailer for the Pac 22 and have been looking through the 4x4 stuff to see if anything could be adapted from that area, but have not really found anything suitable yet.

What about some sankey axles they have disc brakes