Auto Reverse not working

Sargan · 13 May 2018, 20:48

Look for a suggestion ...

Have Indespension Super Roller Coaster 5.5 twin axle trailer.
Brakes are Al-Ko overrun brakes as on many UK trailers.

Braking & hand brake working fine.
But on reversing once the hydraulic hitch coupling comes to end of its travel it locks on the brakes ... they are not ‘tripping out’ the shoes via the auto reverse function. As I have a sloped drive - they lock on as soon as I try reversing up it.

If I disconnect from car ... I can pull trailer up drive fine with my winch ... so confirms the brakes are not locking on other than from road actuator, and Auto-reverse not tripping ... going backwards should force trailing shoe into cam and release the braking effect.

Checked adjustment of brakes multiple times, all seems fine.
The compensator bar where the 4 Bowden cables connect ... has a rod down to the ‘S pawl’ operating lever on hitch.
As rod adjuster was corroded.. replaced both adjuster and clevis assemly (both ends) ends and the 2 rods, set up for zero play.

Still the same ....

Apart from cleaning you don’t adjust (none possible anyway) the auto reverse cam & spring.
Have checked the cams & springs are all free to move

Anybody any suggestions,

diver 1 · 14 May 2018, 08:00

Could I suggest you may have one of 3 problems:

1) brake lining installed wrong way around - look at pics online and be certain you have your brake linings fitted to the correct sides of each drum
2) brake rod/cable between hitch and compensator over tightened
3) grease/contamination of drum / lining

smallribber · 14 May 2018, 19:20

I just did my breaks I second the possibility of the brake pads being on the wrong way round ie Front lining at the back. See this video and the follow on one

http://www.rib.net/forum/f49/many-th...tml#post771711

Dennis

Sargan · 14 May 2018, 23:35

Quote:

Originally Posted by Bigplumbs

I just did my breaks I second the possibility of the brake pads being on the wrong way round ie Front lining at the back. See this video and the follow on one

http://www.rib.net/forum/f49/many-th...tml#post771711

Dennis

Al-Ko and Indespension both state that Brakes shoes are NOT handed, the left & right shoes are identical.
That video is for KNOTT brakes ... my trailer has AL-Ko brakes. Also that video only covers taking brakes off .. does not mention anything about being handed.

Pikey Dave · 15 May 2018, 05:32

Quote:

Originally Posted by Sargan

Al-Ko and Indespension both state that Brakes shoes are NOT handed, the left & right shoes are identical.
That video is for KNOTT brakes ... my trailer has AL-Ko brakes. Also that video only covers taking brakes off .. does not mention anything about being handed.

Have you dropped a hub off to check the linings? The most common problem is rust between the metal brake shoe & the friction lining causing the shoe to swell. This takes up the clearance needed for the auto reverse to work.
The expander adjuster will probably be seized, these are a royal PITA to free off.
If the expander is over adjusted it won't allow the brakes to reverse.
iirc there should be a 2-3mm clearance between the back of the hitch tube & the brake mechanism. I.e there should be a couple of mm backlash in the system, it shouldn't be tight.

smallribber · 15 May 2018, 06:51

Quote:

Originally Posted by Sargan

Al-Ko and Indespension both state that Brakes shoes are NOT handed, the left & right shoes are identical.
That video is for KNOTT brakes ... my trailer has AL-Ko brakes. Also that video only covers taking brakes off .. does not mention anything about being handed.

The follow on video is the important one. I agree this video is about Knott brakes but it is the front and back that is important not left and right

Pikey Dave · 15 May 2018, 07:07

Iirc Alko shoes are identical, left right front back, all the same.

Sargan · 15 May 2018, 11:45

Quote:

Originally Posted by Pikey Dave

Iirc Alko shoes are identical, left right front back, all the same.

That is exactly what manual states and I have always seen on my trailers that have had Al-Ko brakes.

I wish we had far better trailer - stainless steel disc brakes, aluminium chassis, swing up jockey heel, folding draw tongue, step over all non metal mudguards. etc.
Had one US trailer like that - much better (but not legal for UK)

Pikey Dave · 15 May 2018, 11:55

These are about as good as you'll get
http://www.vanclaes.com/standard/index.php?language=en

Sargan · 15 May 2018, 12:01

Quote:

Originally Posted by Pikey Dave

Have you dropped a hub off to check the linings? The most common problem is rust between the metal brake shoe & the friction lining causing the shoe to swell. >>>>>
I.e there should be a couple of mm backlash in the system, it shouldn't be tight.

I striped all hubs fully down each year and fully clean, 3 years ago painted inside with 2 part-epoxy - so back plate keeps rust free, accept the springs, adjusted, expander get rusty.
I clean them all fully and all free to work and individually checked.

I have backed off rod to get 5mm of clearance (manual very specifically states modern couplings require zero clearance- but I'm happy to try)
Need to re-try reversing again now it has been backed off.

The only practical way to get any clearance is to adjust the cone adjuster where rod goes through compensator.
The rod is fixed at coupling end where clevis pin is fixed into S-Pawl. You can screw further in to clevis pin, but very limited or it will foul on the S-Pawl.
Putting play in at compensator end will allow play at coupling end as rod is solid.

paintman · 15 May 2018, 23:21

http://www.al-ko.co.uk/edit/files/ha...m-handbook.pdf

Sargan · 16 May 2018, 13:37

Quote:

Originally Posted by paintman

http://www.al-ko.co.uk/edit/files/ha...m-handbook.pdf

Thanks - I did have that - have you read it, does not really help.

I attach another version that Al-Ko produced for Indespension .... trailer all set as per these instructions (though pretty sparse)

paintman · 19 May 2018, 00:10

Always do before I post a link

If all else fails see if a local caravan dealer's workshop will have a look as Al-ko are common on caravans. I do a lot of bodywork for one in Northamptonshire & they're puzzled too but do say can't diagnose without seeing it although defective/faulty parts & incorrect adjustment were mentioned.

May not be the issue, but note that the link I posted says that on one type of shoe they are indeed handed. Yours may not be that type.

Sargan · 19 May 2018, 00:17

The Al-Ko brakes on my trailer havs shoes that are definitely not handed, I swapped them a year ago ... all 8 were exactly the same.
Knott brakes are handed.

Disconnected the rod tonight and tested reversing ... no lock-up, so for sure it is rod actuating the brakes, and auto-reverse failing to activate is the case.

paintman · 19 May 2018, 00:21

Trip to workshop time.

Sargan · 19 May 2018, 15:37

I think so ... just they have 2 week lead time.

Jeff · 19 May 2018, 16:34

Hard to say given all you have done but is it possible that the auto reverse mechanism is siezed? Replacements not too ridiculously priced. Example here ,,, but different ones for specific hub/brake sizes
https://www.trailertek.com/trailer-p...-and-2361drums

Jeff · 19 May 2018, 18:07

One last check ,,, if the shoes are not correctly adjusted, ie too slack, the auto reverse will not operate. The brakes will bind without going over on the cam. Adjust up until they lock whilst rotating forward, then back off a couple of clicks at a time until they are free. Operate the handbrake on an off a few times between each adjustment to centre the shoes. Do not worry about a slight rubbing noise caused by off centre. If you back off until there is absolutely no sound they are probably too loose.
Apologies if I am teaching grandma to suck eggs as they say [emoji41][emoji106]

Sargan · 19 May 2018, 19:37

I thought that under adjustement could have been cause so rechecked all adjustment.
Tightened until locked up, then backed off until ... if you spin wheel it comes to stop in 1.5 turns.

Manually checked each auto reverse cam ... all free to move if pressed down, and return springs all fine.

I had to change 1 x Bowden cable, so thinking I’ll change the other 3.

Also although I fully clean the expander mechanism I dont lubricate.
One article suggests lubricating expander & auto reverse cam .... just have to find out what to use.
Being dumped in salt water unsure in I should be using Copaslip or some form of chain oil or similar.

Jeff · 19 May 2018, 20:14

Quote:

Originally Posted by Sargan

I thought that under adjustement could have been cause so rechecked all adjustment.
Tightened until locked up, then backed off until ... if you spin wheel it comes to stop in 1.5 turns.

Manually checked each auto reverse cam ... all free to move if pressed down, and return springs all fine.

I had to change 1 x Bowden cable, so thinking I’ll change the other 3.

Also although I fully clean the expander mechanism I dont lubricate.
One article suggests lubricating expander & auto reverse cam .... just have to find out what to use.
Being dumped in salt water unsure in I should be using Copaslip or some form of chain oil or similar.

Castrol Moly lithium type grease is recommended by Alko... used sparingly [emoji6]