16 replies to this topic

[baker_boy]

whats happening is when i put my foot down on the brake it feels like theres nothing there till half way which it then goes hard, and i mean nothing then it suddenly just stops, and then actually starts braking..
weve changed the rear cylinders and the brake shoes only about a couple of months ago, and it didnt do it after that. but it was slowly creeping in again. it was getting worse and worse..what is it?

iv got a 1100 clubby engine. completely standard setup with non servo brakes.

thanks.

p.s. is it worth changing to servo brakes?and whats necessary to do so?

Edited by baker_boy, 06 March 2007 - 04:44 PM.

[taffy1967]

I'd adjust the rear brakes again (they've probably bedded in now after all) and try bleeding the system if necessary.

[baker_boy]

I'd adjust the rear brakes again (they've probably bedded in now after all) and try bleeding the system if necessary.

should you need to bleed them again?

[Bass Man]

Brakes is my next job......

Sounds like you need to rebleed, the air is compressing and giving you the pedal travel,

DO IT NOW DON'T PUT THE JOB OFF BRAKES IS NOT AN AREA TO COMPROMISE

If you are slightly unsure get it done by a good garage it is not worth the risk.

A servo will just make the pedal easier to press, it won't improve the brakes.

(Sorry, rant over...)

[Gr4h4m]

I'd adjust the rear brakes again (they've probably bedded in now after all) and try bleeding the system if necessary.

I agree, I was shocked how much the rears effect the pedal.... or it could be air.... I bet if you tighten the rear up a little bit more you will see the pedal return

[TOMMO0302]

So is there general consensus on how tight the rear wheels should be to turn by hand after adjusting up?

[Minwah]

should you need to bleed them again?

I've often had to bleed mini brakes a good few times to get them working really well. Maybe I'm just C**p at it but I've sure other people have had to do the same.

Definately adjust the rear brakes first tho.

[taffy1967]

So is there general consensus on how tight the rear wheels should be to turn by hand after adjusting up?

The Haynes manual covers this and I just put the back up safely on axle stands and chock the front wheels, release the handbrake and then adjust the brakes by tightening each adjuster with a brake spanner until it won't go any tighter.

Then I back the adjuster off a quarer of a turn until the wheel spins relatively freely. There might be a slight resistance, but so long as their not binding then there shouldn't be a problem.

Once both the rear brakes have been done, I lift the handbrake 3 clicks and then check if to see if the rear wheels are locked solid and won't turn, or at least are very difficult to turn. But of course turn relatively freely with the handbrake off.

If the wheels aren't locked solid on 3 clicks of the handbrake or are turning with ease, then it's worth adjusting the handbrake and that just takes 2 open spanners to adjust the cable on the rear of the handbrake itself.

Anyway that's what i've always done and I imagine someone will either have a better method or perhaps tell me off for failing to do something specific, but i've heard some folk tap the drums to centralise them too at some point?

Edited by taffy1967, 09 March 2007 - 04:54 PM.

[TOMMO0302]

Yeah i did mine according to haynes, its just terms like 'relatively freely' that make you wonder....also, im sure i read on here sometime about people doing them up so they could 'just turn them'.

My front brakes are only about 300 miles old, not too impressive but guess they are still bedding in, after another couple of 100 miles i will readjust the rears again.

[taffy1967]

its just terms like 'relatively freely' that make you wonder....

I meant that the wheels should spin freely, but if there's a tiny bit of resistence or rubbing (usually a scraping sound from the brake shoes), which I've usually encountered then I'm sure that's nothing to worry about.

So long as their not binding.

[Gr4h4m]

After fitting new shoes I spin the back wheels whilst the wife stamps on the pedal to centralise them before I adjust them. IMO I adjust them until I can just turn them (not super tight) I spin around the block and a re-check.

About a year ago I replaced all of the wheel cylinders and I couldn;t get a decent brake pedal... I kept thinking it was air and I tried loads of bleeding techniques, standing on my head etc... I even clamped the front shoes and did them without the drum on.... but the low pedal was just down to needing a little bit more on the rear adjusters. I was pumping the pedal and it would get higher so I thought it must be air but all I was doing was moving the shoes out and therefore the master cylinder didn't have to move as much fluid to get the shoes against the drums. This was all resolved by doing the rear adjusters up a little tighter. Then I got the high pedal I was looking for

[dklawson]

I'm coming to this thread a bit late but would like to add my own observations. The symptoms and scenarios aren't unique to Minis. IF you have long pedal travel before the brakes begin working, you need to do the following simple test. This test can be done while parked.

Push the brake pedal down and note how far it travels AND how it feels. Is it firm or squishy? QUICKLY, lift your foot off the pedal and pump it down a second time. Is the pedal at the same height off the floor that it was on the first pump? Does the pedal feel the same?

If the pedal is squishy feeling after either pump you should consider re-bleeding the brakes as this generally is an indication of air in the system. Air is compressible, the fluid... not so much. The squishy feeling is the compression of the air bubbles.

If the pedal is higher on the second pump and the pedal is relatively firm, this indicates that the drums/shoes are out of adjustment. What's happening is that on the first pump you're moving the shoes out into contact with the drum. By applying a second pump quickly, the shoes don't have time to fully retract. On the second pump a small bit of additional fluid is taken from the reservoir and held in the brake lines giving a slightly higher pedal.

If the pedal MOVES slowly down in either of these tests (as you keep pressure on it) this indicates that you need to rebuild or replace the master cylinder as fluid is leaking past its seals.

[baker_boy]

hey all.

thanks for all the excellent advice ill be re-adjusting the brakes during the week hopefully, as i almost crashed last week in the rain because of the brakes so...they defineately need doing.
ill let you know what i did and what the outcome was.

thanks agen

dave

[YoungUn]

how do u tell if u need new shoes or drums?

[Gibbon]

The shoes are worn when the thickness of the lining starts getting near the rivets. If they look like this shoe in this photo then they need changing! (these shoes had very uneven wear, with less than 1mm of lining remaining at this end, and 3mm at the other end)

 DSCN0103.JPG   408.41K   2 downloads

If the drums are worn there'll be a rim round the outer/inner edge where the shoes have eaten away the metal . I don't know the the exact tolerences before you have to bin them though..... anybody? I believe they can be re-surfaced if not too pronounced.

All the best

Edited by Gibbon, 11 March 2007 - 10:14 AM.