Brakes on a road trailer

[Little Star]

Hi Everyone

Has anyone had any experience of changing the braking system on a boat trailer from hydraulic to cabled brakes? Any advise would be welcomed

 

[sarabande]

Hydraulic do not require the mechanical force of over-run to operate the brakes. Overrun or actuation of towing vehicle's brakes triggers the barking.

Cable brakes need an overrun system to provide the brake function.


So if you change, you may well need a new damper/overrun unit. That can be expensive as they are usually integrated with the hitch. A change to cable will also need some form of auto-reverse system built in to the brake drums.

www.knottuk.com/fileadmin/.../KF085_-_Spreadlever_Brakes.pdf‎

I think it is going to be expensive.

 

[VicS]

Hydraulic do not require the mechanical force of over-run to operate the brakes. Overrun or actuation of towing vehicle's brakes triggers the barking.

Cable brakes need an overrun system to provide the brake function.


So if you change, you may well need a new damper/overrun unit. That can be expensive as they are usually integrated with the hitch. A change to cable will also need some form of auto-reverse system built in to the brake drums.

www.knottuk.com/fileadmin/.../KF085_-_Spreadlever_Brakes.pdf‎

I think it is going to be expensive.

My cable operated brakes do not have any form of autoreverse system in the hubs ( they are bog standard Mini rear hubs with the cables operating the handbrake linkage.) There is a lever on the coupling which manually disables the overrun operation for use when reversing.

 

[Avocet]

Is the OP in the UK? If so, he'll be bound by the "Construction and Use" Regulations. Their requirements vary (as far as brakes are concerned) depending on the age of the trailer. As there is no compulsory registration scheme for small trailers in the UK, it's all a bit of a joke because nobody will know how old the trailer is. TECHNICALLY, they should have an identity plate on them quoting (among other things) the year of manufacture (or more correctly, date of first use)! That will determine whether or not it needs auto-reverse brakes with a damped coupling, or whether simple "spring-over-run" would be sufficient.

Some good stuff on here:

http://www.ntta.co.uk/law/

 

[lw395]

We looked into this.
Changing the entire running gear for parts from a caravan chassis was one option.
Change axles complete.
Change hitch.
Connect with cables.
Anything else looked like a lot of detail work.
We didn't do it in the end, the US trailer went for too much on eBay and we got a good deal on a UK one.

 

[Little Star]

Thanks for feedback already....like you lw395 mine is a US trailer for a 1992 Catalina 22...the hydraulic brakes dont work as yet but am told all it needs is the cylinder from a Morris Minor! but even if i fix it I'm not sure it will be legal.....told it wouldn't be and also as I would be towing with a Volvo V70 which can take it I want to be sure I can stop! so maybe better to look round for another trailer

 

[Bilgediver]

Hydraulic do not require the mechanical force of over-run to operate the brakes. Overrun or actuation of towing vehicle's brakes triggers the barking.

Cable brakes need an overrun system to provide the brake function.


So if you change, you may well need a new damper/overrun unit. That can be expensive as they are usually integrated with the hitch. A change to cable will also need some form of auto-reverse system built in to the brake drums.

www.knottuk.com/fileadmin/.../KF085_-_Spreadlever_Brakes.pdf‎

I think it is going to be expensive.

This might not be the case if you by a Regal or a Binliner which comes complete with trailer from the good ol USA No connection with the car system
as the master cylinder is on the trailer and actuates on the overrun. Seems our road techies hate them so they are not accepted in the UK . Maybe the OP
has such a USA trailer. See lots of them confned to a life in marinas.

 

[mtb]

I hired a big trailor some years ago which had a home made hydraulic system fitted it was rubbish as they'd fitted cables to the master cylinder ( Triumph ) expecting the braking force to be enough !
A morris minor master cylinder wouldn't be big enough would it, I did have a yank caravan which had electrical operated brakes which worked really well the EU pen pusher mob seem to like trailer laws that just don't add up
I got pulled years ago the officer didn't have a clue yet still tried to nick me but lost the will when I argued stating just because a new load of laws have come along why would I now be breaking the law with the same trailor which was legal before

cheers
mick

 

[Avocet]

Thanks for feedback already....like you lw395 mine is a US trailer for a 1992 Catalina 22...the hydraulic brakes dont work as yet but am told all it needs is the cylinder from a Morris Minor! but even if i fix it I'm not sure it will be legal.....told it wouldn't be and also as I would be towing with a Volvo V70 which can take it I want to be sure I can stop! so maybe better to look round for another trailer

Definitely illegal in the UK, I'm afraid. Whether or not you'd get stopped is a different matter, of course!

 

[Lakesailor]

A Morris 1000 master cylinder will be operating 6 slave cylinders. A close coupled trailer will probably have leading/trailing brakes, so be operating 4 slave cylinders. It would depend on the bore sizes.
However a Morris 1000 is a very strange master cylinder to try and fit into a system. There are many more better suited and cheaper.

As hydraulic brakes are not legal on UK trailers it is of no consequence.

The cheapest way to get legal brakes is to buy a caravan chassis (or two) probably £100 to £150 each. If you have four wheels you have to have brakes operating on each wheel if the GTW is over 750 Kgs. The problem would be that you would be stuck with the width of the caravan axle beam as the rubber suspension is not limited to the end of the axle, like Indespension-type units. That is, you can't chop the axle.
Despite this a caravan chassis will still give you a legal tow hitch and brake back plates which could be fitted to your existing hub carriers. The thing to be careful of is that many caravans have fairly low Gross Trailer Weights (1000kgs/ 1300kgs) so the hitches may not be suitable.

 

[William_H]

OP is not too clear on the hitch type. I fitted hydraulioc brakes to my trailer many years ago. I bought an over ride hitch which couples to a supplied single cylinder master cylinder. Note most later cars have dual system master cylinder with 2 cylinders. so no good. Possibly why Morris master cylinder is a choice but also depending on bore size. The wheel units were from a locally built holden car of 1960 vintage. Which suited the stub axles and wheels. One trick I did do was turn up nylon pistons for the wheel untis after the Ali ones corred so much resulting in barkes jammed on. (brakes have been since dismantled and removed due to very limited towing distances and infrequent use now) Not legal I know.
Back to OP if he wanted to go to cable brakes then i imagine this same hydraulic over ride coupler could be used to actuate the cables. It is all a matter of mechanical advantage. Yes this coupler has a metal section that can be dropped in to stop the coupler compressing when reversing.
Here in Oz electric brakes are the go for heavier caravans and boats. Although sometimes we see vacuum assisted or controlled cable brakes. Both systems can provide break away braking and braking controlled by the driver. They often have an adjustment control so the driver can improve the onset of trailer brakes compared to car brakes. Electric trailer brakes seem to be OK in dunking under watrer or at least no worse than hysdraulic or cable brakes.
Probably doesn't help OP and does not address the legalities in UK.(olewill waffling again) good luck

 

[Avocet]

...The cheapest way to get legal brakes is to buy a caravan chassis (or two) probably £100 to £150 each. If you have four wheels you have to have brakes operating on each wheel if the GTW is over 750 Kgs. The problem would be that you would be stuck with the width of the caravan axle beam as the rubber suspension is not limited to the end of the axle, like Indespension-type units. That is, you can't chop the axle.
Despite this a caravan chassis will still give you a legal tow hitch and brake back plates which could be fitted to your existing hub carriers. The thing to be careful of is that many caravans have fairly low Gross Trailer Weights (1000kgs/ 1300kgs) so the hitches may not be suitable.

Actually (and I appreciate this is splitting hairs somewhat), it still wouldn't guarantee legality. What the C&U regs say is that the braking system "...shall satisfy the requirements of..." (and then it goes on to quote the EC Directive or the ECE Regulation. You'd have no "documentary evidence of compliance" if push came to shove. It's true that provided the all-up weight of boat and trailer was within the maximum weight on the caravan's chassis plate AND you used the entire, unmodified braking system from the caravan, you'd PROBABLY comply, but as soon as you start mixing bits from two caravans, it gets extremely difficult to prove.

All that said, I doubt the police would go into that level of detail unless there was a fatality.

 

[Lakesailor]

Yes. That is true. Unfortunately. Of course as the age of any of the components and the trailer cannot be certified it'll be difficult to show that you need to comply.
Hydraulic brakes certainly don't though.

 

[Little Star]

So hydraulics are defintaely illegal in UK and therefore I've got two options. spend the money (how much???) adapting the trailer which otherwise is very sound or buy a new or secondhand one. only really be towing it at the beginning and end of season so want to limit cost obviously. new would be too much....just taking a quick look and i think i'm lookingv at at least 2-2.5k. Any ideas best place to find second hand trailer for 22' lifting keel boat?

 

[Lakesailor]

A hitch will be around £250 and brakes and suspension/hubs about £250 per wheel. Less than £1300. http://www.indespension.co.uk/Trailer-Parts/Braked-Suspension-Units/ISSU028.html

Once you know the spec of your existing back plates/drums it may be you can change the working parts without replacing the hubs or wheels.
I'd certainly do some research before jumping in to swapping.

 

[TangaraToo]

If you go down the route of converting yourself with second hand parts I would look for a horse trailer rather than a caravan.
They are always twin axle and normally rated at 3.5t. Once converted just swap the plat over.

 

[Avocet]

So hydraulics are defintaely illegal in UK and therefore I've got two options. spend the money (how much???) adapting the trailer which otherwise is very sound or buy a new or secondhand one. only really be towing it at the beginning and end of season so want to limit cost obviously. new would be too much....just taking a quick look and i think i'm lookingv at at least 2-2.5k. Any ideas best place to find second hand trailer for 22' lifting keel boat?

Depends how handy you are and what equipment you have at your disposal, really. I recently rebuilt my own trailer (not a boat trailer) and found a couple of brand new 1 tonne braked Avonride axles on eBay for £100 each. They were cheap (I imagine) because they were only 3' wide and who on earth wants a 3' wide trailer that can carry a tonne?! Depending on what your existing suspension units are like, maybe you can buy something like that and then just use the hubs and backplates on your existing suspension units?

 

[Little Star]

Thanks guys for the input ...this is realluy useful.
So take it whilst i am a reasonably competent DIYer when it comes to heavy duty stuff like trailers count me out. also if i'm going to spend the money i want to know it is legal so maybe means getting it tested?
Avocet/Lakesailor...you both sound though your up north....my boat/trailer is on Ullswater...do either of you have any recommendation who could do this work?

 

[Lakesailor]

This guy does lots of work on existing trailers. His prices seem on a par with internet suppliers. http://hornbys-trailersandtowbars.co.uk/contact-details#
He's a very nice bloke.

 

[Avocet]

I'm in North West Cumbria - about 40 miles from Ullswater, but I do all my own work, so couldn't recommend anyone, I'm afraid. HOWEVER, my "day job" brings me (peripherally) into contact with the vehicle conversion and bodybuilding industry. I'm afraid I don't have a huge amount of faith in many of them to know and understand the regulations. Perhaps you should stipulate that you ant them to take the trailer (when finished) for a voluntary (non-statutory) Individual Vehicle Approval test?

This is relatively new, and does NOT apply retrospectively to old trailers like yours, but it's a good way of getting a "Minister's Approval Certificate" from VOSA, that will confirm, beyond any doubt, that the trailer meets the CURRENT legal requirements. I didn't do that with mine, to be honest, and I think it's probably "over-kill". Also, in the case of a boat trailer, I'm not quite sure how you'd do it because things like the lighting requirements are based on the shape an size of the trailer (which will obviously be different when carrying a boat compared to when its empty). Chances are, most body builders or trailer makers you approach will say "you what, mate?!".

I wonder if another option might be to say something along the line of "please can you make this trailer comply with the Construction and Use requirements relating to braking, for an all-up weight of (whatever the boat and trailer combined weigh) tonnes and give me a receipt specifying that"? Although its the driver at the time who is responsible for the legality of the vehicle and trailer, at least then you've got an invoice and receipt for the work which shows you acted in good faith and had every reason to believe it DID comply, so you can get back at them should you be stopped!

What you actually need, is:

(i) Proof that the brakes themselves meet the requirements of Directive 71/320/EC (as amended) for the maximum weight of boat and trailer combined (and give yourself a safety factor). I've got a copy of a brake test report for the Knott brakes I used. Any bodybuilder ought to be able to get hold of that from the brake manufacturer).

(ii) Proof that the towing hitch is suitable for the maximum weight of boat and trailer combined. (There is usually a plate on it. The Bradley one I bought for my trailer has one).

(iii) Proof that the hitch is compatible with those brakes (I haven't got that, to be honest).

(iv) tyres with a maximum load capacity (between them) adequate for the maximum weight of boat and trailer combined.

(v) a breakaway cable (they're cheap and easy to get).

Chances are, if "plod" stop you, they'll only really look at the plate on the hitch and maybe the max load on the tyre sidewalls. If the axles themselves come with a plate on them (some new axles do) they might look at those. Obviously, the weight you're allowed to tow is limited by the smallest of the component capacities above (plus what your vehicle can legally tow).