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MG Midget and Sprite Technical - Rear brake lining advice please

For 3 years my rears have worked fine however handbrake beginning to fade and adjuster stuck. So took off the off side drum to look.
The upper shoe has worn down on the trailing edge while the front edge has worn very little. The other shoe is hardly worn at all and is worn the same consistency all along its length.

No scoring on the drum.

Obviously I need to replace the worn shoe at least. However this is also not normal consistent wear. Can anyone explain where I went wrong when relining last time please? And being the one that wants to know why - can anyone explain what has happened or caused it?

Also done 18000 miles since this lining was replaced. Is this good, average, or poor?

Thanks in advance, Dave
Dave Squire

Dave I had to read this twice - are you really relining your own old shoes?
David Smith

No Dave, replacing the shoes (with new ones) - (with the linings already attached). I did this three years ago and changed them all.

Just wondering why just one of the two in the same drum has worn like this when the other one hasn't?
Dave Squire

Dave,
l am surprised they have worn significantly in just 3 years /18k miles. Unequal wear on the shoes could be one of the double ended pistons sticking. Or the shoes aren't centerings as they should. When you fit the shoes, do you put a little smear of copperease on each of the contact points where the shoes rest against the backplate?
Guyw

Can't remember Guy.

Just looks like the one shoe has done all the work and then only the trailing edge which is odd as the leading edge on the worn shoe is next to the cylinder. As the adjuster is at the other end where the wear is I am really struggling with understanding what has happened.

Will remember about light grease on edges where in contact with back plate when replacing. Anything else you can think of for when I reassemble? Should I put a light grease where the shoes go into the adjuster and cylinder?

I have both Castrol High temp and copper grease as well as Castrol general purpose.

Thanks
Dave Squire

You do have the leading edge of both shoes pointing the right way then?
Guyw

It would give the symptoms you describe if one of the slave cyl pistons was partially seized or not achieving full movement.
David Smith

Sorry chaps; been working on house this afternoon then hijacked for dads day.

I thought I knew about shoes and direction when I did them. Will have to check.

And will look at cylinder.

Sounds like that's all there is to check then.

Slightly tired out right now so its a look 2 morrow after work job.

Let you know later.

Cheers.
Dave Squire

Hello All, resurrected thread as I have the new parts now.

So which is the leading edge? I have looked at the worn ones and they have been put on with the opposite ends to one another. That is the end where the lining is to the edge of the metal is next to an end where there is an inch or so of bare metal.

As one of them has worn worse than the other it looks like I need to replace the one that is less worn orientated as it is and the worn one replaced with a new one that is on the other way around.

Concur?

Not too worried about doing it more often than necessary but concerned that I only just caught it before it went down to the metal.

Thanks in advance, Dave
Dave Squire

Dave

This is a pic from the WSM of a quarter elliptic off-side rear brake. Apart from the position of the wheel cylinder, the orientation is the same for semi elliptic.

Obviously, the near-side is a mirror image.



Dave O'Neill 2

Great Dave, that's a pic I didn't have. Thanks.
Dave Squire

18000 is really good

you must have the usa version... here they always wear out with lots of meat left on the bone ...just runs out of adjuster

My understanding is you cwn use old mini shoes and just grind off the side to get good funtioning shoes that will wear down nice and use up all there meat.
prop

Mini ones fit without any grinding down. The friction lining is wider on a mini shoe, but still fits the Spridget drum so you get a bit more braking action on the rear. Good if you are using uprated front pads.
Guyw

I had the shoes on the right ways around and the slave works OK.

Obviously something caused the wear so I have put the new shoes in with light high temp grease on shoe seating and edges where they rub on back plate. Drum on and tests OK when turning by hand. Handbrake OK as well. Adjusted OK.

Can only do one side at a time so will look at other side soon ish.
Dave Squire

This thread was discussed between 19/06/2016 and 08/07/2016

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