Caravan Brake Servicing Risk

ben66 replied on 27/06/2019 07:02

Posted on 27/06/2019 07:02

Both me and my partner attended separate Practical Caravanning training' courses in Evesham put on by the Caravan and Motorhome Club and led by a very informed and entertaining guy called Vaughan. On both he suggested that because Caravan brakes operate differently to car brakes we'd be wise to ensure that any brake servicing we get done is done by a caravan mechanic rather than a normal garage mechanic because the latter don't usually know that caravan brakes are different. .All well and good we thought however we then found it impossible to find a caravan servicer available to check our brakes prior to our holiday so we booked it into the same place that a 'knowledgeable' bloke on our caravan site was having his brakes tested. 

Ever since we've been concerned about Vaughan's advice however when I google about how caravan brakes work and I think I know the difference between van and car brakes, I cant see how not knowing the difference could lead to a car mechanic doing something during the testing that could lead to a real adverse impact - I don't see what the real risk is.

The only thing i can think of is as follows....

He might test the brakes as the caravan moves forwards and, providing they work correctly, he then ticks off that test.

He then tests the brakes as the caravan moves backwards and to his surprise he finds that they don't apply.

At that point he might be driven to ask around/google and ultimately finds the answer and so then proceeds to complete the test with that knowledge or he might adjust the brake more and more until,. even in its collapsed position, the shoes can reach the drum and they work and he then ticks of that test without re-testing the forward operation.

I don't know if it is possible to adjust the brakes so that they could be applied even from a collapsed position but if it were and he did that, I would have thought that as soon as the van moved forwards and the brake release switch spring restored the shoes to their non-collapsed position, it would be impossible to pull the van any further forwards by hand such that you would immediately know there was a problem.

Maybe you might pull it forwards with a car but even then i would have thought you would feel that the van wasn't freely rolling.

What I can say is that I didn't notice any issue when I towed it back from the garage however when I set it in place on the caravan site, I didn't have any need to pull it forwards by hand so I will be checking that when I next visit.

So please can anyone advise what the risk or risks are of having a car mechanic test caravan brakes - what could he do wrong that could then have a real consequence?

Please note I only took it to the garage to test the brakes and nothing else.

thanks

Ben

 

 

 

MollysMummy replied on 27/06/2019 09:54

Posted on 27/06/2019 09:54

Maybe Vaughan should just stick to testing/training people & leave the mechanics to mechs. Any mechanic will be able to see the difference in operation between a hydraulic slave cylinder drum set-up of a car and that of the all mechanical lever & rod set-up of a caravan. 

Milothedog replied on 27/06/2019 10:37

Posted on 27/06/2019 10:37

I think if Vaughan  knew what he was talking about he would of also made people aware of the limited reuse procedure for the hub nuts on modern caravan chassis, a far easier mistake to make by someone not in the know. 

As said above, he should stick to what he is skilled at.

compass362 replied on 27/06/2019 10:54

Posted on 27/06/2019 10:54

I would imagine most members(like me) that tow have a company/dealership or a independent service engineer to do all the mechanical /tech stuff for them.... I may be wrong. 

My job is to fill the fresh water , empty the grey water & of course the toilet needs seeing to.

My OH doesn't have a job or anything to do with our caravan.... other than enjoying the holidays... when ive towed us to our destination. 

Is there any other way to caravan.... but enjoy your holiday. 

Wildwood replied on 27/06/2019 15:51

Posted on 27/06/2019 15:51

My feeling is that virtually all brake adjustment is done professionally as part of a service by a caravan engineer. Unless he is doing it as a favour for a friend, I cannot see a car mechanic doing this, but it is a point.The difference is that caravan brakes are not activated by the brake pedal but are overrun models. The brake is applied when the towing vehicle slows down and the caravan pushes against the tow ball and depresses a valve. I would have thought that any good car mechanic would see this, but mistakes are possible.

The actual mechanism in the hub is similar to many cars, so adjustment there should not be a problem. It is basically knowing how to set the overrun mechanism correctly that could go wrong, which in all probability might mean the brakes were less effective.

Pulling the caravan on a flat surface would not tell you if there was a problem, as the overrun will not operate. It would let you know if the brakes were binding, but if you have been on a run with the caravan this sounds unlikely.

MollysMummy replied on 27/06/2019 16:05

Posted on 27/06/2019 15:51 by Wildwood

My feeling is that virtually all brake adjustment is done professionally as part of a service by a caravan engineer. Unless he is doing it as a favour for a friend, I cannot see a car mechanic doing this, but it is a point.The difference is that caravan brakes are not activated by the brake pedal but are overrun models. The brake is applied when the towing vehicle slows down and the caravan pushes against the tow ball and depresses a valve. I would have thought that any good car mechanic would see this, but mistakes are possible.

The actual mechanism in the hub is similar to many cars, so adjustment there should not be a problem. It is basically knowing how to set the overrun mechanism correctly that could go wrong, which in all probability might mean the brakes were less effective.

Pulling the caravan on a flat surface would not tell you if there was a problem, as the overrun will not operate. It would let you know if the brakes were binding, but if you have been on a run with the caravan this sounds unlikely.

Posted on 27/06/2019 16:05

no valve involved in a caravan brakes. When the over run operates, it pulls a rod which in turn pulls various levers & fulcrums which pushes the shoes outwards inside the drum

DaveandVicki replied on 28/06/2019 09:05

Posted on 27/06/2019 10:54 by compass362

I would imagine most members(like me) that tow have a company/dealership or a independent service engineer to do all the mechanical /tech stuff for them.... I may be wrong. 

My job is to fill the fresh water , empty the grey water & of course the toilet needs seeing to.

My OH doesn't have a job or anything to do with our caravan.... other than enjoying the holidays... when ive towed us to our destination. 

Is there any other way to caravan.... but enjoy your holiday. 

Posted on 28/06/2019 09:05

I refer to the previous answer from my learned friend. laughing

0001 replied on 28/06/2019 10:01

Posted on 28/06/2019 10:01

Perhaps it may be that a caravan engineer uses a  torque wrench when fitting the new hub nut and wheel nuts and all the mobile engineers I've used take you round and re torques the wheel nuts in your presence and gets you sign they have been done and I prefer to have the gas, electric etc checked at the same time so now my 2019 sticker is emblazoned on my A frame so you and I know it should be safe and after our freinds wheel came off their van some years ago we both now carry our own torque wrench.  

 

MollysMummy replied on 28/06/2019 10:22

Posted on 28/06/2019 10:01 by 0001

Perhaps it may be that a caravan engineer uses a  torque wrench when fitting the new hub nut and wheel nuts and all the mobile engineers I've used take you round and re torques the wheel nuts in your presence and gets you sign they have been done and I prefer to have the gas, electric etc checked at the same time so now my 2019 sticker is emblazoned on my A frame so you and I know it should be safe and after our freinds wheel came off their van some years ago we both now carry our own torque wrench.  

 

Posted on 28/06/2019 10:22

None of which really is anything to do with AN Other car mechanic not having the knowledge/ability to work on caravans' brakes ...... 🤔

And I don't like stickers emblazoned on anything 😉

Dorset Diver replied on 28/06/2019 10:33

Posted on 28/06/2019 10:01 by 0001

Perhaps it may be that a caravan engineer uses a  torque wrench when fitting the new hub nut and wheel nuts and all the mobile engineers I've used take you round and re torques the wheel nuts in your presence and gets you sign they have been done and I prefer to have the gas, electric etc checked at the same time so now my 2019 sticker is emblazoned on my A frame so you and I know it should be safe and after our freinds wheel came off their van some years ago we both now carry our own torque wrench.  

 

Posted on 28/06/2019 10:33

And the purpose of the torque wrench is?  

Tinwheeler replied on 28/06/2019 11:19

Posted on 28/06/2019 11:19

The OP asked “So please can anyone advise what the risk or risks are of having a car mechanic test caravan brakes” 

In my opinion there are far more risks involved in letting caravan dealership ‘technicians’ play with the brakes.