Auto Reverse not working - Page 5

Bigplumbs · 10 June 2018, 17:04

Quote:

Originally Posted by Sargan

When I start reversing up drive all the weight is on rear axle ... i.e stern of boat.

In fact for first couple of metres the wheels on front axle due to height of tow hitch don't touch ground .... after first 2m all 4 wheels back in contact

Not particularly steep drive, just a slope at the start

It is the rear axle wheels that lock up for sure, if I put in low ratio I can force trailer to moves - and rear wheel skid, showing brakes are locked on.

I am sort of thinking more & more the coupling is 'over driving' so instead of being light touch and the auto reverse kicks in ... it has full car force , and locks the shoes solid.

If I drive fwd ... brakes release and trailers rolls fine.

In the best possible terms I would stop all the faffing and make a short bar (use threaded rod) that you can flip over to lock the hitch in one place when you reverse up the slope. If you look at the hitch I am sure this would be easy

Dennis

Sargan · 10 June 2018, 18:55

Not so easy ... it would require fabrication and some welding ...... though it may come to that.
The couplings that were designed for that had a cut out behind teh damper top 'flip-over' a limiter for reversing.

Observation
Today when putting boat away .... the boat is on my drive handbrake applied - brakes hold fine it does not roll fwd.

Then hooked up winch to pull it into boat shed ..... inadvertently I had left hand brake on .... winch puled it in fine, no extra load .... so from that point of view - with handbrake applying brakes it appears auto reverse does work.

Now handbrake is in 90 degree position/ 12 o'clock when applied (as it should be) .... but it did not move backwards to 2 o'clock as it is supposed to ... but that could just be the ES spring unit is weakening.

This may reinforce the 'thought' that the coupling may be at fault and over-driving the brakes.

Bigplumbs · 10 June 2018, 19:13

I think the fact that the wheels are almost off the ground is a factor also. Have you tried taking the whole setup to a different incline and trying it

Dennis

Sargan · 10 June 2018, 20:19

No ... been reversing up this drive with this boat for 5 years, and other for another 5.
Next time I am out with it I will find another slope to try.
My drive is only a 3% gradient.

beamishken · 11 June 2018, 16:39

Quote:

Originally Posted by Sargan

I have not been able top get to a point where adding slack makes it work.
Added loads ..fon't forget any slack I add also affects normal braking.

What im suggesting is keep adding slack untill you can reverse and then see if you have brakes in forward that will prove the auto reverse in the hubs is working and would suggest a hitch travel or damper issue.
Did you replace the rusty shoes you pictured?

Sargan · 11 June 2018, 17:19

Quote:

Originally Posted by beamishken

What im suggesting is keep adding slack untill you can reverse and then see if you have brakes in forward that will prove the auto reverse in the hubs is working and would suggest a hitch travel or damper issue.
Did you replace the rusty shoes you pictured?

I have done that many times ...
got to point of something like 100mm of slack ..still unable to reverse up drive.
At that point rods sagging badly.

I don't have time to try it again before it goes in on Friday ... have to mark this down as beaten me.

beamishken · 11 June 2018, 18:53

Quote:

Originally Posted by Sargan

I have done that many times ...
got to point of something like 100mm of slack ..still unable to reverse up drive.
At that point rods sagging badly.

I don't have time to try it again before it goes in on Friday ... have to mark this down as beaten me.

Ok im sure everyone will be interested to know what the final fix is hopefully it doesnt cost too much

Bigplumbs · 11 June 2018, 19:02

Quote:

Originally Posted by Sargan

I don't have time to try it again before it goes in on Friday ... have to mark this down as beaten me.

I think this has beaten all of us as well

Sargan · 11 June 2018, 19:28

I'll be sure to let forum know. Coupling is my thought train.

Orwell boy · 11 June 2018, 20:34

Forget all that adjusting and trying ,jack the trailer on axle stands on the flat ,remember the facts ....they are the shoes should always disengage when the wheels are turned backward (except under handbrake conditions ) ,,,use a ratchet strap between the hitch loop and the winch post to simulate the underbrake and then fully back position ,by hand or using a wheelnut wrench go round one by one and see if the wheels are locked forward but should fairly easily turn backwards as you will feel the shoes hop out ,adjustment wont really matter and can be tweaked later within reason ,, if its going to work then all wheels will turn backwards by hand , if this works and all is good you can look for the problem poss with the hitch ,there is a possibility that someone has fitted a damper of say a 3500kg goods trailer so your hitch can never compress fully ,if you can compress fully with the strap and turn the wheels backward then this will rule that and reverse damper is too strong and your not compressing enough under normal reversing ,,just so much easier with it all blocked up and simulate breaking with a strap

Sargan · 11 June 2018, 22:05

won't be able to do that as away .. and only back to take it in Friday.
Nobody has changed damper ...had trailer for 5 years and until now all been fine.

However maybe something physical ...i.e. coupling coming back further than supposed to ...and therefore overdrive of brake did has so much force it prevents auto reverse dropping shoes out.

Sargan · 12 June 2018, 10:57

Damper is the one as fitted from new - never been changed.
Worked fine reversing for 5 years.

The coupling retracts under pressure from car and pushes back out when pressure off.
So all moving OK.

Is it moving too far ? don't know.
Not aware on any adjustments.

No time this week due to being away.
It's booked in for Friday.

beamishken · 12 June 2018, 12:57

Quote:

Originally Posted by Sargan

Damper is the one as fitted from new - never been changed.
Worked fine reversing for 5 years.

The coupling retracts under pressure from car and pushes back out when pressure off.
So all moving OK.

Is it moving too far ? don't know.
Not aware on any adjustments.

No time this week due to being away.
It's booked in for Friday.

The damper can fail and lose its pressure, its designed so the coupling goes in slow to stop the brakes snatching on, if its weak that could be your problem.
But you havent determined where the fault lies yet so I guess its wait and see what the outcome is

Sargan · 12 June 2018, 14:24

After 6 weeks of loads of ideas ... you are right not identified the cause :-(

Sargan · 15 June 2018, 19:53

OK ... trailer booked in, 100 mile round trip.
It was with them all day .... you asked for update on what the cause was.
They checked damper & coupling - no fault.
Checked my set up of brake shoes - all fine.
Checked set up of rods & Bowden cables all fine.
Then stripped all 4 hubs, all assembled as should be ...

Final result - they have no idea what is causing this, and unable to resolve.
They did involve Indespension HQ .. nothing new suggested.

They are going to ask other Indespension outlets see if anyone else has had similar issue.
Good that my mechanical skills were not the cause ... but annoying no resolution.

paintman · 16 June 2018, 10:28

Frustrating.
But if it's worked fine for 5 years including reversing up the slope you've suddenly started having this problem with I'm not convinced that there isn't a problem with the system.
Something has clearly changed but it's identifying what that is.
Strikes me that Indespension need to test at the place you're having the problem

beamishken · 16 June 2018, 10:33

Very frustrating but I agree with Paintman has to be an issue if its worked for all those years previously

Sargan · 16 June 2018, 11:18

Been into Indespension, they can’t find cause ... they ar3 not going to come to m6 house, but fault can be seen on the slight slope in their yard. If they can’t fix it I can’t force issue with them, not under warranty. They are going to ask all Indespension outlets via a group mail, maybe someone will have a solution.

My latest thought is that ... the drums have lost 3mm off wall thickness at the wear/contact area, so 6-8mm in diameter increase.
Now this should be OK, as the adjusters are still able to set up brake shoe gap ...if they couldn’t accommodate then drums would need changing.
Perhaps though this along with some wear on shoes alters the working angle of autoreverse cams and prevents them operating.

There were 2 lips formed either side of contact area, which showed the ~3mm wear... I machined off these lips last year (brakes fine for 12 months after that). And deliberately removed no material from the wear area ... just removed lips as new shoes were very slightly wider than previous shoes (friction material width)

If they don’t come up with idea by end of next week, will have to make up some ‘anti reverse brake operation block’.

beamishken · 16 June 2018, 12:13

Have you changed those rusty shoes you pictured?

Sargan · 16 June 2018, 12:28

Quote:

Originally Posted by beamishken

Have you changed those rusty shoes you pictured?

yes ... but honestly - rust on shoes is irrelevant ...the friction lining is what is key, and no build on of rust on edge where it slots into cam.

You are putting mild steel into salt water - it rusts.

British trailers are years behind US trailers in that respect .... one US trailer I owned had hydraulic Stainless Steel disc brakes, those were totally unaffected by salt water.,