Simon's new Xantia V6 and Leaf blog

[Mandrake]

Cleevely think they've identified a problem with the shoes that were sent - they are apparently for the 2011-2013 Japan built Leaf - which uses an electric parking brake.

They're sending some replacements although this time a different brand as well. The puzzling thing is all Leaf's up to 2017 use the same disc but apparently the shoes changed from Japan made to UK made!

I'm going to assume the fixing hardware on the hub backing plate that the shoes attach to differ even though the disc inner diameter is the same. Fingers crossed! Should have them in time for the weekend.

[Mandrake]

New shoes have arrived, these ones are Delphi instead of Triscan and are also for 2014+ Leaf instead of 2011 to 2013.

The design is very similar and would pass as the correct part at a casual glance (and did for me) but there are some significant differences in dimensions. Spot the differences:

The new, presumed correct shoe is on the left.

Hopefully the weather cooperates on the weekend.

[NewcastleFalcon]

New shoes have arrived, these ones are Delphi instead of Triscan and are also for 2014+ Leaf instead of 2011 to 2013.

The design is very similar and would pass as the correct part at a casual glance (and did for me) but there are some significant differences in dimensions. Spot the differences:

The new, presumed correct shoe is on the left.

It was the only logical explanation for your difficulties Simon, I presume they don't want you to send the wrong ones back, they certainly caused a lot of unnecessary hassle for you.

I was quite pleased my Leaf got through its annual MOT this week. Last year I was adjusting up the handbrake immediately before the test and was a little too cautious about not adjusting it up to possible binding on levels, and it just scraped through. Got it adjusted just right for the test this time though.

Neil

[Mandrake]

Well I'm stuck again!

I've fitted the new shoes and they are definitely a much better fit than the previous ones and they do match the originals so I'm pretty confident they are the right part, BUT....

The drum slides over the shoes easily and if I turn the drum while it's just pushed onto the studs by hand it turns freely, however as soon as I put a couple of nuts and spacers on to pull the disc properly square it binds.

It's happening on both the left and right sides. Loosen the wheel nuts slightly and allow the disc to move back the tiniest amount and it turns freely again.

Anyone have any suggestions as I don't understand what's going on here...

Why can the drum clear the shoes perfectly for 95% of sliding on then suddenly start binding when it's fully pulled home ? The adjuster isn't even extended yet it's fully wound in...

At the moment I'm looking at having to put the old shoes back in yet again and ask a garage to do the work as I'm completely fed up after a second weekend is wasted on what should be a straight forward job. I'm really getting to a point now where I just don't want to be doing work on cars anymore as it's incredibly frustrating and unsatisfying with every job going wrong in some way.

[mickthemaverick]

That sounds to me like the shoes are fractionally wider than the originals causing the edge of the shoe to bind on the face of the disc when tightened. If so a little run of a flap disc down the edges of the shoe backplate should sort that out

[Mandrake]

That sounds to me like the shoes are fractionally wider than the originals causing the edge of the shoe to bind on the face of the disc when tightened. If so a little run of a flap disc down the edges of the shoe backplate should sort that out

Sorry but I'm struggling to visualise what you're suggesting ?

[mickthemaverick]

I'll try and do a sketch, stand by

[Mandrake]

There's no way the shoe can touch the front of the disc - there is a lot of excess inner drum. (at least 15mm)

The disc is also not touching the backing plate - with the shoes removed I can tighten the wheel bolts without introducing any drag.

[mickthemaverick]

I am thinking that the edge of the shoe indicated by arrow number 1 is rubbing on the face indicated by arrow number 2 when you tighten it up.
So a quick shimming down of the edges may solve your problem and I would use a flap disc on the grinder. Does that help?

MTM construction

[Mandrake]

I am thinking that the edge of the shoe indicated by arrow number 1 is rubbing on the face indicated by arrow number 2 when you tighten it up.
So a quick shimming down of the edges may solve your problem and I would us a flap disc on the grinder. Does that help?

I can't see how that would happen when the shoe is entirely within the inner radius of the disc.

The only thing the edge labelled 2 might touch is the backing plate / stone shield but I've checked that with the shoes removed.

[mickthemaverick]

Having seen your pics I wonder if the 'drum' part of the disc is not fully square, ie corrosion built up as in the sketch below?

MTMO

[mickthemaverick]

If you have a rubber wheel you can put on a drill I'd bolt the disc to the hub back to front so the drum is facing out, then use the rubber wheel against the outside of the drum to drive it round while holding a file, assuming there is clearance between the file and lug nuts, if not use abra paper, squarely on the inside face of the drum and thus removing any material which shouldn't be there.

[Mandrake]

I've filed a little bit back on the shoe where the bottom adjuster fits and I can now bolt the disc on without it binding at all.

However I now have the same problem that was there with the car before I did any of the work - which is that if I back off the adjuster to the point where the wheel isn't dragging with the handbrake off, it will not lock the wheel when turned in reverse when the handbrake is applied - I can overcome the brake in the reverse direction by turning the tyre by hand.

If I increase the adjuster until I can't turn it backwards by hand then release the handbrake there is still a lot of drag.

This is exactly the problems was seeing a year ago on the car before the handbrake cables seized.

However the handbrake cables have been replaced, the discs and shoes and yet I'm still seeing the same issue.

I really can't understand this. The brake lever arm which pushes the shoes apart at the top pivot seems to be working fine and pushes the shoes apart by nearly 5mm at the top when the handbrake is applied with the disc missing, so there is plenty of action there.

Stumped and fed up with the whole thing and wish I didn't start any of this work. I just seem to be getting deeper and deeper into trouble.

Did I mention how much I hate drum brakes ?

[mickthemaverick]

Given that with the handbrake off you need it to be free I am now thinking it is too free at the top, ie the 5mm travel you have is not sufficient to lock the wheel. So you need to open the top of the shoes a fraction more at there starting point so the 5mm presses them harder onto the drum. I'd try putting a 2mm shim of some sort between the top of the shoe and the operating lever so the top starts moving from a closer position to locking. Shimming where the red lines are, a horseshoe staple would be a test material.

BFTT

[NewcastleFalcon]

Reading between the obvious lines, I think you at the Room 101 stage. I put drum brakes into my own personal vault in the FCF room 101 back in 2019. Didn't serve any practical purpose but vented my displeasure on a job at the time.

viewtopic.php?p=623711#p623711

..and bringing up the 200 replies.....

Drum brakes and all the silly springs, handbrake linkages, adjusters, and primus inter pares these ridiculous fasteners

Neil