How do I remove the rear brake drum?

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baz_d69
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How do I remove the rear brake drum?

Post by baz_d69 »

Simple really. Or it should be. I'm trying to remove the rear drum to service the brakes, which failed the MOT, even once adjusted tight.
I remove the wheel. I undo the retaining screw. Drum won't move off, though rotates freely in either direction (adjuster is completely slackened off).I tried a hub puller. Nothing, no movement what so ever.

This is the odd part to me: There's a 3rd screw on the brake drum, which is accessible through the drum, but clearly behind it, i.e. it doesn't hold the drum on. If I undo it, it pushes the drum out, albeit at an angle, at which point the drum locks up again. Could someone tell me exactly what that screw is, and how come that little thing seems to move the drum (slightly), but my hub puller has no chance?

What am I missing? This is holding my MOT back :cry:
aupickup
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Post by aupickup »

that 9rd screw you see holds the rear half shaft on

your old drums may have a lip on the outer edge where the brake shoes are, this happens after a number of years, and it is prob this that is holding the drum, so you need to get a rubber faced hammer and hit the the rear of the drum around its circumference, make sure the rear brake adjuster is slackened right offf
MarkyB
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Post by MarkyB »

Do the third screw up again and tap the drum back level.
A little bit of levering opposite the side where you tapping with the hammer can help.
Once one side has moved a fraction swap lever and hammer and do another bit working round the circumference as Aupickup says.
cormorant
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Post by cormorant »

Be careful now you have loosened that 3rd screw that your half shaft seal does not leak when it comes time to fit everything back together again. Mine did just because I disturbed it exactly as you did - I had to replace the gasket and rubber ring
mike.perry
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Post by mike.perry »

The two screws you removed are retaining screws not tightening screws so when you replace the brake drum tighten it up fully by using a couple of wheel nuts, then replace the screws. If you tighten it up using the screws you will ruin the slots and give yourself trouble next time.
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taupe
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Post by taupe »

Baz

Just a thought - youre not using the wheel studs to try and pull the drum/ hub off are you??

The brake drum comes off seperately from the hub and bearing. Should just tap off if its loose as aupickup says
simmitc
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Post by simmitc »

The suggestions above will most likely sort your problem. If the drum is badly worn, then you might like to consider fitting a new one - always match new shoes and drums on both sides. If you get a new drum then you can lightly cut the old one and it will come off in pieces.

Another possibility is to refit the wheel nuts and tap the studs in a little before removing the nuts again. This can help free the drum off, but has the problem that once you've pushed the studs in too far, they will catch on the cylinder and prevent the drum turning. You can, of course, pull them out again using the nuts.

I would certainly be prepared for a new O ring and gasket now that you've disturbed the half shaft.
Pikey
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Post by Pikey »

As previously mentioned your drums are probably quite worn and the shoes are now sitting in tracks in the drums hence the jamming.

Seeing at the drums turn easy enough just undo/unscrew/back off the adjusters and the brake drum will literally fall off.

Dont go levering the drum off you'll just trash whats left of possibly good linings.

Total nightmare to do on automatic adjusting rear brakes though, you cant back them off.

Steve

bmcecosse
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Post by bmcecosse »

Usually - you can! There is often a small hole in the backplate - possibly sealed with a rubber/plastic plug - which you remove, and insert screwdriver to lever the auto-adjust mech away - and allow the shoes to collapse inwards - thus releasing the drums!
In the case of the Minor - just wiggle and tap - NO levers required - the drum will fall off - provided the adjuster is backed right off AND the handbrake mechanism is not adjusted up too tightly! May be worth taking the clevis pin out - where the cable attaches to the lever - and make sure the cylinder can slide vertically in the slot while you are in there!
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baz_d69
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Post by baz_d69 »

Thanks for your help everyone, Roy came through trumps again. I HAD been using the studs to try to pull the drum off. Realising my error, a few taps with a rubber mallet got it off straight away. Drum looks like new, it was the rear cylinder that had seized up. Cylinder and shoes replaced, drum is back on, just need a new brake line now.

Thanks again!
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Post by bmcecosse »

May as well change them both - by that I mean - put new shoes and cylinder on the other side too - and new brake pipes on both (be aware these are the unusual 3/8 BSF thread !) - then you know you don't have to worry about the rear brakes for at least 4 weeks!
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