Override brakes

[atouchofglass]

Greetings Everyone
OK confession time
I had no idea what over ride brakes were
Then one of the members said mine weren't working
So I wondered how many other novices out there have questions on how they work

So here is my understanding of how it works
The tow-hitch has a large spring in the body of the hitch which compresses when the car is slowing.
This allows a post at the back of the hitch to press onto/engage the brakes
The brakes being the ones usually engaged when using the handlever.

How'd I do guys?

Photos and more intelligent explaination are appreciated


Cheers
Atog
^{the not so mechanically minded}

[Deleted]

Atog, you're just about right on the money, you left one thing out. the bit at the back of the coupling pushes on the lever which is either mechanically or hydraulically connected to the brakes.
The big spring in the coupling MUST be of the correct rating otherwise if it is too stiff the brakes will not apply. For more info go to the Alko site and look up override couplings, from memory the springs come in 2000Kg rating and 1500Kg rating. so if you have a light van go for the lower rating spring, you will have better braking.

Frankidownunder.

[millard1399]

G'day atog, I can provide photos, but I dunno about a more intelligent explanation...

These photos show the mechanical override braking system...








Force "A" in picture 2 is created either by the weight of the van pushing forward onto the coupling (as in slowing down from speed), OR by the tow vehicle pushing the coupling backwards (as in reversing). The little "coupling lock" shown in picture 1 is flipped over onto the coupling shaft (the short black length behind the coupling) to prevent the coupling being pushed backwards when the towcar is reversing. Otherwise you would be applying the brakes on the caravan while you are trying to reverse your rig. However, you must ALWAYS remember to lift that coupling lock back out of the way of the shaft when you are intending to travel in a normal forward manner (otherwise you will be travelling with the caravan brakes inoperable).

Hope this makes sense.

cheers,
Al.

[Deleted]

Not the best van braking arrangement invented ... but probably better than nothing driven sensibly.

[philouise]

oh-i've got to add my comments.
never have i seen such a well set out diagram. well done.
also, sometimes a brake master cylinder thing sits near that fulcrum thing with a plunger thing that puts pressure on the fluid in an alloy hose that runs along the chassis to the wheels(instead of the cables).
woops, just noticed frankidownunder mentioned hydraulic.
o.k. -- i'm going.
Phil.

[millard1399]

Don't rush off, Phil! As a Franklin owner, you will be familiar with the hydraulic version of the overriding braking system. Franklin started putting that system on their vans back in the mid-1960s from memory. Was a big selling point at the time.

---------------------------------

I thought I'd post a close-up of that "coupling lock" so that people know what it looks like. I've seen a number of photos of vans for sale on that auction site, where the coupling lock fitting was missing. If you didn't realise a van was supposed to have one, you'd never be the wiser...



----------------------------------

Maintenance of mechanical override braking systems:

Quite apart from getting your friendly mechanic to overhaul the brake pads, machine the drums, make adjustments at the wheel, etc, there are things you can do as the owner to ensure the braking system is kept in a good operating condition. There are a number of moving parts, starting from the coupling and working back to the wheels, that should be greased or oiled on a frequent basis...



As well as that, you should check the cable for any fraying, and check the cable clamps behind the wheel hub to see if they are holding on tight.

cheers,
Al.

[Deleted]

Just wish to add a couple of photo's to this thread as it has some great information, the inner working of the over ride brake.

[Deleted]

Thanks so much for this. We just became the keepers of a 75 Arrow, and this helps a lot with maintenance and what to check. We see a lot of people in ads have added electric brakes. Is this a good idea? Also our caravan family includes what looks like an early Viscount Valiant. It only has the handbrake. Any thoughts if that arrangement is sucky and dangerous, and what to change? That one needs some work, so we can throw it into the shallow pit of ideas and money.

Cheers,
The Tinkers

[glennv]

In my opinion, electric brakes are the ducks nuts on larger vans for the following reasons.

1. They give you brake control of the van from the cabin of the car, meaning that if your van starts to wobble, you can flick the lever, apply a little bit of brake and pull it into line.

2. If using level riders / weight distribution hitches, hydraulic brakes require more inertia to activate, which may mean really no braking at all.

3. The newer controllers have push button boost, which means more braking gain can be applied by push button (say hilly country), but the ability to return to normal setting easily.

4. You don't get the sensation of the whack in the tail with lectric brakes.

But, be prepared to part with $2,500 if you have them installed (including controller). Less of course if you can fit them yourself.

[tim]

Hi I need some advice on brakes. I'm shopping for a largish (20'+) van, with not enough budget, so I've been looking at some fairly scruffy vans. A lot of vans of this size are unregistered and haven't been towed for a while. The last two I've looked at had what at first glance looked like mechanical over-run brakes, but on closer inspection it appears to be only a handbrake.






Is that unusual on such a large van. When did the law change to ensure that large vans had brakes?

I'm only planning on towing the van very occasionally, ultimately I would want to convert to electric brakes, but could these handbrake only vans be converted to mechanical over-run by fitting the correct coupling and a cable kit? 

Tim

[rebswa]

Dec 11, 2014 8:20:37 GMT 10 tim said:

Hi I need some advice on brakes. I'm shopping for a largish (20'+) van, with not enough budget, so I've been looking at some fairly scruffy vans. A lot of vans of this size are unregistered and haven't been towed for a while. The last two I've looked at had what at first glance looked like mechanical over-run brakes, but on closer inspection it appears to be only a handbrake.






Is that unusual on such a large van. When did the law change to ensure that large vans had brakes?

I'm only planning on towing the van very occasionally, ultimately I would want to convert to electric brakes, but could these handbrake only vans be converted to mechanical over-run by fitting the correct coupling and a cable kit? 

Tim

My guess is, as it has a handbrake, and it is not an override coupling it probably already has electric brakes.
And converting a handbrake to an override brake is not a good idea.

[tim]

Yes, its not an over-ride coupling, but I don't think there's any electric brakes, I couldn't see any sign of wiring emerging from the brake drum. Only the front axle is braked, the rear one has no drum at all.

When did electric brakes start to be commonly used?

Tim

[Deleted]

I think you will find they are electric brakes Tim,wouldn't have a had a hand brake only,take a drum off and you will know for sure.
Back then electric brakes were only required on the leading axle,so no worries there.
Electric brakes have been around for decades,but became standard in the mid eighties on Aussie vans.
Cheers
hughdeani

[Deleted]

Dec 11, 2014 8:20:37 GMT 10 tim said:

Hi I need some advice on brakes. I'm shopping for a largish (20'+) van, with not enough budget, so I've been looking at some fairly scruffy vans. A lot of vans of this size are unregistered and haven't been towed for a while. The last two I've looked at had what at first glance looked like mechanical over-run brakes, but on closer inspection it appears to be only a handbrake.

Is that unusual on such a large van. When did the law change to ensure that large vans had brakes?

I'm only planning on towing the van very occasionally, ultimately I would want to convert to electric brakes, but could these handbrake only vans be converted to mechanical over-run by fitting the correct coupling and a cable kit? 

Tim

Hi Tim

Depending on what State you live in will depend on what you will need to have in regards to brakes. It has nothing to do with the vans age. I am guessing these van's your looking at are not registered? So to get a permit to move or to register in QLD you would have to have the appropriate brakes for the weight of the van. Otherwise you will have to get a towing company to move the van on your behalf. The braking system is not a good place to try and save money on, you only have one life so what is that worth ?

I have now checked your profile you are in Hobart, Tasmania, is that correct ?

Cheers Lawrence

PS Tim I just did a search on Tassy rego requirements www.transport.tas.gov.au/registration/buying-selling/re-issue_after_3_months_of_expiry,_cancellation_or_written-off  from the bit I have read you will have to get the van inspected and whoever does these inspection would be the best person to ask what is required

[tim]

I've contacted the owners, they are going to see if the local mechanic can clarify, unfortunately they aren't very mechanically minded and they've never towed the van. If it was a bit closer I could go and have another look, with a toolkit and a big jack, but its a 4 hour round trip from here, and time is short.

Tim

[bobt]

Tim

Most modern cars are not legally permitted to tow a trailer with a weight greater than 750 kgs unless it has brakes.

Good luck with your hunt.

bobt

[tim]

Indeed, hence my concerns. My current vehicle is not rated to tow a van of this size even with brakes, so I will have to hire a 4WD ute. I'd prefer over-run brakes for the simple reason that not many of the hire vehicles are fitted with electronic brake controllers. Unfortunately the guy selling portable brake controllers has disappeared in the last few weeks.

Tim

[tedalley]

Tim Hi.
I personally think that if your van was a stationary park van then it might just have a handbrake.

How far do you have to tow it to get it home? 'cause I wouldn't trust the brakes on a van that has been stationary for a long time.

My suggestion would be to get a mate with a 4WD and hire a car trailer.
Put the van on trailer then you can get it home safely.

Then you can check brakes and everything else at your leasure.

Ted

[atefooterz]

Or like my Vic Rego only, expired 1985, park van NO handbrake! Only overide. Luckily my heavy van tames a non braked , at that time 950+kg classic, with its own breaks and when also using the 6 speed manual gears, one wonders if the van needs any. Existing Holden set up was renewed- new fluid lines, master cylinders etc re invent hand brake for static parking & road worthy cert, still have not used the overide ones yet.

[tim]

This van is a bit big for a car trailer, its a 23' x 8', which works out to 8m total length by 2.4M. Its about 2 hours from home on some fairly windy narrow roads. I would probably have to have it towed on a flat tray, at great expense.

I've pretty much decided to keep looking.

Tim

[Malcolm]

Can anyone show me how to adjust early cable override system at break drum 1973 Oxford

[Mustang]

Apr 29, 2017 7:12:01 GMT 10 Malcolm said:

Can anyone show me how to adjust early cable override system at break drum 1973 Oxford

Google "How to adjust override brakes" 


Scroll down to page 2.
www.alko.com.au/wp-content/uploads/2014/10/Mechanical-Drum-Brakes-Replacing-Brake-Shoes.pdf

If this dosn't help, sign up to the forum & post some images.
Cheers

[Malcolm]

Thank you for your help,we are looking for a site to tell us how to adjust mechanical lever brakes, two small square brake linings. 
We could post a photo Cheers Malc