daft question really

[robert_374565247]

is there any situation that a caravan should roll backwards when the handbrake is applied. Just had our van serviced and with the hand brake applied the van is able to roll backwards. I took it back to the service people and they assured me this was the correct operation. they jacked the van up applied the hand brake and showed me that the wheels lock in forward rotation but are free to turn in reverse rotation. is this right.

The van is a 2002 abbey expression 470.

 

[Dustydog]

See New Members topic.

Cheers

Dustydog

 

[Jaydug]

Your service people demonstrated that the brakes are working exactly as they are supposed to.

 

[TD42]

when a van handbrake is applied it is possible for the van to roll back A few feet but the brake lever should jump to the vertical position& stop the van.you should be able to check this by pulling on the brake & pushing the van backwards

It's not possible to pull the brake on to this position normally

 

[whitetop]

The brakes are designed to release when the caravan is reversed. As already said, once on a pitch etc, move it a couple of feet forward to reset the brake mechanism.

When the handbrake is applied after that the caravan should not move.

For what it's worth, if a car or caravan is jacked up and the handbrake is applied, the wheels will not move.....so nothing proved there.

 

[ProfJohnL]

Hello Robert,

No its not a daft question, and I can fully understand your concerns.

As you are new to caravanning you may not be fully aware of the way the caravan braking system works. The system is called 'overrun braking' and it relies on the fact that when the car and caravan are both moving forwards, if the car brakes, the caravan effectively tries to run into the back and push the car. The hitch coupling begins to compress and in turn pushes the handbrake lever up which begins to apply the caravan brakes.

This system is quite old, but it does provide a fairly reliable low cost method of applying the caravan brakes. The same thing will happen when you try to reverse the caravan using the car. The caravan brakes will begin to apply, and if this was allowed to continue obviously the car would have great difficulty in reversing the caravan. Way back and up until the 1970's when you needed to reverse a caravan someone had to jump out of the car and flip a lever on the caravan hitch which prevented the coupling from pushing the handbrake lever.

In more recent times and this applies to your caravan, the clever chassis manufacturers have developed cam levers in the brake drums that detect when the caravan is moving backwards, and the cams move and prevent the brakes from acting on the drums when the hitch is compressed.

So what you have experienced is normal and expected. I hope that the caravan handbook would have an explanation of this for you. It is always a sensible thing to have chocks ready for the main wheels of the caravan whenever it is being uncoupled, and most especially on a slope.

 

[dougie_374468830]

If the handbrake is applied fully(vertical on ratchet system and past the flip-up point on strut type) there is enough tension to re-apply correctly adjusted brakes if the caravan rolls backwards.

If you jack up one side to demonstrate this you will not release enough tension, if you do both sides (one side at a time if necessary) the brakes should lock when doing second side. You will probably hear a bit of a clunk as they do so, more so on the ratchet type.

An easy way to test, apply brake and push caravan backwards it should only move around 6" then stop.

 

[robert_374565247]

thanks for taking the time to reply gentlemen

peace of mind - pricless

 

[Chris_374413356]

many years ago many caravanners were caught out by applying the hand brake on an incline and the van started moving backwards.

I was one of them, I still have nightmares when I think what could have happened.

 

[colin-yorkshire1]

hi robert

the info given above is correct but it is not the whole story it is difficult to describe correctly and in great detail but basically if the van is stationary and the hand brake is applied the van WILL roll backwards if pushed. also if the van has just been reversed and the handbrake then applied ditto the van WILL roll backwards, however if the van is pulled forwards slightly and then backwards a few inches "WHILE APPLYING THE HANDBRAKE TO THE VERTICAL POSITION the van SHOULD NOT roll backwards the reason the van should not,run away backwards is to do with a spring cylinder that is attached to the handbrake rod that stops the van rolling backwards when applied,

please read the following exerpt from the ALKO manual it should give you the answers you are looking for.⇨

""if the handbrake is NOT

fully applied to the last tooth (i.e.

vertical) and is set to some lesser

position than the full vertical. The

spring cylinder is not fully compressed

and problems will almost

certainly arise after the caravan/

trailer has been uncoupled from the

towing unit.

If the caravan/trailer is parked on a

reverse slope or if it is pushed

backwards, the shoes and expanding

clutch will tend to move with the

direction of rotation (reverse).

This movement puts pressure on the

spring-loaded auto-reverse lever,

causing it to collapse. This releases

the shoes from the drum and the

caravan/trailer will run away.""

Operating the Handbrake

""Always chock the wheels when

parking the caravan/trailer on sloping

sites.

For successful parking on a slope or

steep hill, the operator need only apply

the handbrake with one hand while

gently pushing the caravan/trailer a

centimetre or two backwards.

The user must supply this small but

essential backward movement to

ensure that the fulcrum of the

transmission lever moves past the

point of reverse, thus preventing the

lever from collapsing as it would

normally do when reversing.""