Silly question, sorry..

Feb 19, 2017
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So, hypothetically. If someone had their '99 Abbey Spectrum 520 jacked up to check the brake system, and 'accidentally' rotated a wheel backwards just slightly, then can no longer get it to rotate forwards.. (You know how all the manuals say NEVER rotate it backwards but none say what to do if it happens?). Cables are showing a bit of corrosion and brakes are binding after standing for most of a year so needs fixed! Just don't want to make the problem worse. Any idea how to free it again?
 
Mar 14, 2005
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Hello Ryan and welcome to the forum.

I'm sorry but I cannot answer your question onthis occasion, as brakes were not part of my role. But suffice to say there is rarely a "silly" question, its the people who are silly when they don't ask when they really should.

Sometimes the answers aren't what you may want, especially when there is a safety aspect involved.

There are a number of contributes who do know their braking systems and may be able to help. Hopefully they'll be along before too long.
 
May 7, 2012
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Not a silly question to me. Technical questions are not my thing, but there will be someone along soon I think with the answer.
 

Damian

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Mar 14, 2005
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There is only one way of sorting this out and that means drums off and a full service of the brakes.

Whilst it does say not to turn the wheels backwards, actually that does no harm if the handbrake is off (think what happens when you reverse??).

It is only when the handbrake is on and the wheels turn backwards that the reverse mechanism drops in and shifts the leading shoe to its new position.

With your van it may have the older castellated nut type of bearings which are easier for DIY repairs or it has the Euro axle with the One Shot nut arrangement.

Which is yours? then more info can be given.
 
Feb 19, 2017
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Thanks for the responses guys. It's the one-shot nut type. I can't recall if I rested my hand on one tyre while working with the other and it seemed to rotate back slightly then wouldn't move forward again.. Can't recall the exact circumstances unfortunately. As a side-note, the stored energy spring up-front is falling apart. I've ordered a replacement but I'm not sure if that can contribute to the binding problem? The outer housing of it has rusted away so it's not containing the spring very well anymore.. The divider where the brake rod attaches to the bowden cables is showing some signs of corrosion so I guess that could affect the balance of things.. I'm sure I'll figure it all out as I go, I've worked with cars for forever but these are slightly different.
 
Jul 15, 2008
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RyanArthur said:
....................... Any idea how to free it again?

Drop caravan off jack.
With handbrake off, reverse caravan 1 meter .....all brake shoes should now be free of drums if they are correctly adjusted and cables moving freely.
 
Feb 19, 2017
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I did have a feeling that'd be the case, thanks for confirming that. I have a tendency to brute-force everything so I didn't want to hook it up and drag it until the tyre exploded.. Appreciate the responses!
 
Feb 19, 2017
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Can I ask about the 'stored energy spring' upfront? I have a replacement enroute, but after having a quick look at it, I really dont understand its function or how it works...
 
Feb 19, 2017
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Thanks for that. It explains how to correctly adjust it, but not really what it does. Looking at the diagram and the unit on the caravan itself, it seems to be putting forward force on the brake rod as the handbrake is applied, which would make sense. Just not sure why a spring is necessary - but nevertheless, mine has burst out of its housing so may be putting some force on it even with the handbrake disengaged. That would maybe explain my binding issue? I'll hopefully get a look at it tonight... My free time is usually assigned weeks in advance, there's so little of it :(
 
Jul 15, 2008
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......I would advise to take another look at the help sheet and familiarise yourself with the differences between caravan overrun brakes and car drum brakes.
Not least the fact that due to their design, the brakes can allow the caravan to run backwards for up to 30cms when unhitched.......even though the handbrake is fully applied.

The purpose of the spring is fully explained in the help sheet........it is to compensate and take up slack that occurs in the mechanism during this 30cms backward movement.
 
Feb 19, 2017
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Apologies for the earlier post, I was at work and didn't have time to read every line of the document. In replacing the spring unit it seems that its purpose is to transfer force from the handbrake lever to the brake rod by pushing the spring against the 2 locking nuts forward of it, thereby pulling the brake rod forwards and acting on the bowden cables as a result. Given that my original spring had burst out of the cylinder, it was putting at least some forward force on the rod and causing the brake binding. All good now and thanks for the responses.
 
May 7, 2012
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It just occurred to me, there is a Haynes Caravan manual which will help greatly if you are doing your own maintanence on the caravan. Probably available on Amazon but certainly Halfords stock it.
 
Nov 16, 2015
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Raywood said:
It just occurred to me, there is a Haynes Caravan manual which will help greatly if you are doing your own maintanence on the caravan. Probably available on Amazon but certainly Halfords stock it.

Yes i have on a very handy book , cover allmost everything you might need to know about caravanning.
 

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