Wheel Bearing Replacement

[Damian]

Quote "http://www.al-ko.co.uk/braking-maintenance.htm

That's another page on Al-Ko's website which refers to annual maintenance of checking brake lining thickness through the back plate inspection hole.

That advice is totally pointless if they also require the drum to be dismantled."

Yet again you are quoting what the caravan owner can do to his braking system as a matter of the limited maintainence he can do, as to go any further needs the kind of tools not normally owned by the average owner.

 

[RogerL]

Why would the owner need to check every 12 months through the inspection hole IF every 12 months a workshop needs to dismantle the drum.

The one task is pointless if the other is going to be done.

 

[Damian]

Looking through the inspection hole gives ONE aspect of the brake condition, and that is how thick the lower shoe pad is.

It gives no indication of the state of the upper shoe, nor the web of the shoes, nor the state of the drums inner friction surface, nor of the condition of the reverse mechanis, retaining springs, adjuster or shoe sliders.

As stated previously, you must do what you think is right, I will do what I know to be right.

 

[Martin_E]

Roger,

Can you actually tell me that you could 100% say by looking through the inspection hole that the break shoes are not starting to delaminate or break up, I would find it very hard to believe that this is possible, this would only be one reason for taking the drums off.

 

[RogerL]

Damian/Martin

Why would Al-ko issue such a "pointless" recommendation for owners to carry out AT THE SAME FREQUENCY as a full internal inspection.

If Al-Ko published nothing and we were debating the relative merits of different maintenance regimes then a difference of opinion would be inevitable - BUT - Al-Ko publish a specific maintenance task, which the trade says isn't enough.

There's a clear difference of opinion between Al-Ko's published requirements and the trade's requirements - so who do we believe, Al-Ko who design, engineer and build the brakes or the trade?

 

[RogerL]

Martin - why do caravan brakes need much more rigourous maintenance than car DRUM brakes - the internal linkage is slightly different to allow auto-reversing but there's no automatic adjuster to clog up with dust and there's no hydraulic cylinder which might leak - caravan drum brakes should need less attention, not more.

 

[Damian]

As quotes from the Al-KO site seem to be thing to copy and paste (for some users)I thought Roger may be interested in this one:

"For your own and other road users safety, It is important to ensure your braking system is correctly adjusted and maintained.

We recommend that this task is carried out by your local AL-KO Service Centre. Their workshop engineers have received extensive training by AL-KO service personnel and are equipped to ensure your caravan is road worthy and safe.

For safety reasons, and to comply with the impending EU regulations, we now only supply brake shoes to our Service Centres in complete axle sets (ie 4 shoes per single axle). During your next service, if your brake shoes are found to be worn - a new set of shoes will be fitted to each brake drum"

As stated previously, and now becoming boring, the instructions in the handbooks are for those who want to do "something" to give them peace of mind that at least the lower shoe has some friction lining on it.

Car brakes are used a lot more than caravan brakes, and it is the LACK of use which can cause more problems than over use.

However, this is the last posting on this matter that I will be making.

I know what is right, I know what is the safest route to take and will continue to follow the requirements of Al-Ko to their service technicians.

I hav eno idea what point Roger is trying to make, all I do know is that looking through a very small hole in a backplate of a braking system is not of any real use whatsoever.

 

[RogerL]

The point I'm trying to make is that Al-Ko shouldn't publish an annual requirement to inspect without dismantling IF the real requirement is to inspect annually after dismanltling.

If Al-Ko gave consistent advice, there would be no discussion.

It's for Al-Ko to have the last word - I'll abide by it.

 

[Sedo]

Can I just say, bearings can actually degrade from standing still.

If, as in some cases the caravan is stored near to a source of vibration, e.g. main road, heavy industry etc., it can cause the bearing (ball, rollers etc.) to shimmy on the outer and inner race.

This in turn produces ripple in the races and the moaning you sometimes hear.

I've had to replace bearings in industry for the same reason in machines in a similar situation, you just don,t get the bearing life you should.

Just a thought.

Tom

 

[colin-yorkshire1]

sorry guys but i dont understand the point being made in respect to sealed for life bearings and brake assemblies just because a hub assembly HAS a sealed for life bearing does not mean the whole hub including brakes are sealed for life and maitenance free, only the bearing is sealed not the whole hub. my fishing barrow has sealed for life bearing too but thst does not mean the wheels dont have to come off to mend a punture.

the reason alko and for that matter some car maintenance books dont metion stripping down the hubs and the practice of using one shot hub nuts and dust covers is to disuade the average owner from doing any maitanance and leave it to the pro's however the expierienced diy'er with a few extra tools would have no trouble doing the work.

taking the hubs off a 100 times would not effect the durabillity of the sealed bearings alone the only problem is if the inner race is seized onto the stub axel then the bearing is destroyed removing the hub this can be avioded by the use of a little HMP or copper grease on the stub axel on re assembly.

I have done this job a dozen times on different cars and a couple of times on the van the new nuts and hub caps are available from a local workshop for about a tenner and my brakes will be done in the next couple of weeks before I take the van out in the spring because I noticed last time the van was used the brakes squealed on overrun.

colin

 

[JimC]

Hi Colin

Quote-: taking the hubs off a 100 times would not effect the durability of the sealed bearings alone the only problem is if the inner race is seized onto the stub axel then the bearing is destroyed removing the hub this can be avoided by the use of a little HMP or copper grease on the stub axel on re assembly

That is what I believe has happened with mine.I can't prove it but I think the previous service agent did not clean and lubricate the stub axle.

Regards Jim

 

[Sedo]

Jim

The bearing could be siezed or just and interference fit.

To be designed to be drawn on and off regularily, one would think they would be transition fits or at best light interference, the problem, as you probably know, is that the inner can eventually 'slip' round the shaft if the fit is too slck.

Lubricating the shaft can exacerbate this.

That's why we come back to the old problem of competent people, and that's why people like Alko insist on servicing at recognised service outlets.

I must have fitted and removed hundred if not thousands of bearings in my life and I've seen them removed and fitted in all different styles, hammers and drifts, screwdrivers, mallets, pullers, presses et el.

Once when asking if a bearing fit was too tight, the answer was 'yeh, we need a bigger hammer'.

So I for one can see exactly where Alko or anyone in the situation is coming from,

If you think the dealers have the skill and finesse to fit the bearing properly then trust them.

You could ask how they fit the bearings in the hub, sealed for life is like any other bearing.

Tom

 

[readcaravans]

as one of alko`s approved service centres for over 10 years, i can say that hubs are required to be removed when completing an annual service. this is fact, and for the reasons which damian has gone to some considerable length to explain.

 

[Guest]

Without trying to upset anyone I was amused at the 'blurbs' on ALKO' webpages.

For example:

We now supply over 80% of the caravan market, with a technologically advanced chassis concept, which is unsurpassed in terms of quality, reliability and performance.

Chassis supplied to the UK Caravan Manufacturers are designed using the latest CAD packages in our Engineering Department, here in the UK.

Yes, they certainly do supply the majority of the industry, but 'advanced technology??'. The braking system is taken from the very earliest brake systems ever used and is a combination of rod linkage and Bowden cable. My dad's 1932 Riley had that. The chassis uses a torsion design which I remember was available on Morris Minor's in the early 50's. Nut held brake drums were standard on Volkswagen Beetles from the late 40's. They also used a steel torsion suspension system which lasted well into the 60's, before they decided it was out of date.

Before anyone starts throwing me in the 'sin bin' again, I do accept that the chassis is effective, and they use modern materials, but I also do think they are being a bit 'tongue in cheek' with their self esteem. I am not quite sure how a CAD design package will improve a Bowden cable, but you never know.

After all, this is the same Company that stated that shock absorbers were not required on their 'advanced chassis' but now fit them to improve handling.

To conclude, I am happy with my van and its ALKO chassis, but as for being that much better technically, than my old 1970's van with its Peak chassis, in many areas I am not so sure..

 

[Martin_E]

Roger,

If you are not happy with the information that has been given on here by reputable service engineers then why not send an email to Al-Ko perhaps they could confirm what you have been told.

 

[RogerL]

Martin - I did that in 2008 and posted the response in this thread on 25/2/10.

I don't understand why Al-Ko's website still just recommends annual EXTERNAL checking - what's the point if annual INTERNAL inspection is needed.

It's a waste of time/money to do the external inspection !!

I've no doubt that trade contributors are just repeating information given to them on Al-Ko courses - so why do Al-Ko give different advice to owners? Or is it only me that can see the pointlessness of doing both an external and internal inspection?

 

[gary]

Knowing you Roger, I would guess you know the brakes on your van fairly intimately? how many fellow caravanners can say the same?

I would say then 'the trade' are not simply following ALKO's advice, because like most caravanners they don't know what yours or any other set of brakes are like, the only way they can find out is to remove the drums and inspect them intimately!

Anything less would be sub standard, simply as that!

 

[RogerL]

Still doesn't answer the question why Al-Ko don't mention internal examination againt "Annual Maintenance" on their website or Owner's Handbook.

Why don't Al-Ko tell owners clearly what needs doing and how often?

Accurate service schedules aren't rocket science - my car owner's manual tells me the cambelt needs changing every 60,000 miles - it doesn't tell me how do do it but so what at least I know to get it done. Al-Ko simply do not tell owners that their brakes need internal examination every year.

I'm not arguing about what should or shouldn't be done - I'm arguing about the continued discrepancy between Al-Ko's information given to owners and the information given to the trade.

 

[xtrailman]

Will some please take the dogs bone away?

 

[SteveW77]

Several years ago, a young man who used to be my apprentice took a job at the local Volkswagen dealership. He was told he would have to undergo a 3 month trial. At the end of three months, he was called in to the office and his work was reviewed. The only point they raised was the fact that he had drawn 2 split pins on every service he had undertaken. He was asked for an explanation and when he replied that he removed the rear hubs for inspection and cleaning, he was told that it was not on the service schedule and as such was not authorised. He was told that in future he was to do only what was on the service schedule, no more & no less. He was also asked to pay for all the split pins he had used. He told them in no uncertain terms what they could do with their split pins & their service schedules. He like me was not prepared to put his name to any safety aspect with out carrying out a thorough visual examination.

Steve W

 

[colin-yorkshire1]

hi roger

I think the reason the inforamtion is different to the trade is because alko (and by the way it is not just alko some car manufacturers do the same) dont believe that the owner "joe public" should do any maintenance on the brakes that should be left to the service engineers only.

this assumes that the van will have the brakes done when serviced profesionally so all the owner is required to do is have a quick look at the lining thickness, stating that the hubs are sealed for life with maintainance free bearings and a once only use nuts re-enforces the belief that the hubs do not need to be removed.

if they gave all the information on how to do the maintenance to the owner via the service manual then joe the dope may well strip the hubs down incorrectly and damage the parts or not rebuild them right. so its better the owner doesn't know.

 

[RogerL]

Colin - I'm not suggesting they publish HOW to do it - just publish what needs doing.

 

[JTQ]

Being very perverse Roger the trouble is they publish exactly what to do, then tell their agents that's not at all the right thing to do!

It would be better just to have said "take it to the dealers every year", and not as they do publish the details of what you have to do.

Are we seeing two sides of Al-Ko, the German principal and the UK satellite who have experience that the published method is not enough?

What ever, what a mess of miss leading and conflicting information, so un-German.

 

[Gafferbill]

.....It is very easy to design a drum brake that allows easy maintenance.

In fact most vehicles that still have drum brakes, have the facility to tap the drum from the hub after the wheel and two small retaining screws have been removed.

Whether the wheel bearing is a 'sealed for life type' is irrelevant.

Since Alko have designed their wheel hub and brake assembly the way they have would suggest that the assembly does not require regular maintenance considering the annual mileage of most caravans.

Remember that the tow car does most of the braking.

As a case study my caravan with an Alko chassis has travelled 41500 miles from new.

The only brake maintenance that has taken place is adjustment to the operating cable, greasing of the overrun mechanism at the hitch and regular inspection.

The brakes are still in 'as new' operating order.

I fully appreciate that those who pay a mechanic to service their caravan expect the mechanic to take responsibility for his work.

The mechanic may feel he has to service the brake assembly to cover himself.

Alko's design has made an easy job a lot harder if this regular maintenance is indeed necessary!

 

[SteveW77]

In fact most vehicles that still have drum brakes, have the facility to tap the drum from the hub after the wheel and two small retaining screws have been removed.

In my experience, most vehicles with drum brakes do not have this facility, a few have, but most modern vehicles with drum brakes are in fact have a similar arrangement to Al-Ko.

Steve W