Braking News!

[Boomlander]

Hi all, Took Jethro out for a spin yesterday and at the first corner I applied the brakes and they locked!
Luckily we were only yards from home and I drove back with the brakes dragging.
Pulled the offside front wheel and firstly noticed only one drum retaining screw present - is this usual or should there definitely be two as the drum is held in place by the road wheel?
Managed to free off the shoes and removed the drum and found one of the cylinders would move out but would not return.
It has a ring of rust around the top of the piston so I have decided to replace all cylinders and shoes as I suspect they are probably in need of renewal.
More work......

[Boomlander]

Now turns out that the nearside front drum is locked solid on the hub and won't come off and the rear brakes are locking on as well even when the handbrake is used.
Time to send the car to the garage - this is way out of my comfort zone!

[surfergirl]

Hi,
Do you use the car much? sounds like it may have been standing. Its not that bad a job to replace the wheel cylinders and shoes, just order the pipe that connects the cylinders at the back as this always seems to be rusted in and its quicker to stick a new one in than mess around with the old one.
The drums should have two countersunk screws holding them, but I have got away without them in the past. It sounds like the brake cylinders are sticking which is why the drum locks.

[chesney]

If they're all locked solid, I would suspect the master cylinder, though from your description of the slave cylinders they need replacing. A Minor going to the British Leyland show at Peterborough last year had a similar situation when the brakes locked on, they had to bleed off the pressure from the master cylinder from the back union and drive it to the next services I believe!

[bmcecosse]

It will cost a FORTUNE at a 'garage'....it really isn't hard to change brake cylinders. One screw is fine (doesn''t really need ANY) - even BMC eventually realised one was enough on Minis etc... The drums will come off - just bang them with a heavy hammer - but protect the drum with a lump of timber.

[Boomlander]

I would prefer to tackle the work myself but I don't have a suitable work area to do the job comfortably.
With my aging knees and back I can no longer work on the concrete drive where my carport is located.
I have ordered all the necessary parts including new drums and a master cylinder and there is a family run classic car renovation and repair centre in town who would be able to collect the Minor on their own transporter.
I guess two or three hundred pounds in labour if they have to renew the master cylinder.
Such a shame that the previous owners did a fine restoration job but neglected one of the most important areas on the car!
Anyway thanks for all the replies folks - much appreciated as always - I will let you know the outcome!

[bmcecosse]

New drums?? Unlikely they will be needed..... I sympathise with your knees and back - just back from a day changing sleepers... Put down a thick rug/old carpet when working on the car!

[kennatt]

its not simply the pedal sticking down ,if unused it may have stuck to the shaft,worth just pulling it back up first,before anything else.

[Boomlander]

Turned all the snail adjusters right back this morning and the drums seem to be turning without sticking.
I did notice that there was virtually no free play on the brake pedal when it should be 3/4"
The manual is a bit vague about adjusting the clearance - do you have to release the locknut and then wind the yoke in or out to adjust? I assume that without the proper clearance the master cylinder piston will not be returning correctly and causing the brakes to jam on?
Anyhow I will be taking the car out shortly for a test run to see if the brakes are working correctly but I will still have all the components renewed to be on the safe side.

[rayofleamington]

other than sticking cylinders, and m/c not returning to 'vent' position the 3rd possibility is that the car had old (pre-used) flexi hoses and had a dot5 fluid fitted.
It's rare to get problems but it's not impossible to make the brake flexi's swell up by using odd fluid combinations. As they are reinforced, they swell and close up the inside channel... result being you can push fluid through at high pressure but it's not going to return.

However, the most likely cause is 'just' a problem at the wheel cylinders.

[Boomlander]

New drums?? Unlikely they will be needed..... I sympathise with your knees and back - just back from a day changing sleepers... Put down a thick rug/old carpet when working on the car!

The old drums look to be the originals and are very rusted and grotty so as they are fairly inexpensive I may as well renew them especially if the front offside has to be clouted to bits to get it off!
I carried a railway sleeper across a field in my younger days and would not enjoy the prospect of a whole day humping the damn things. Luckily we now have machines to do the lifting and shifting on our lines!

[bmcecosse]

Take care if doing a 'test run'....the brake pedal doesn't need 3/4" free play - you are thinking of the clutch! It does need a 'little' free play - so as long as it's not 'solid' it will be fine. The section of line we are working on would indeed benefit from a 'relay' - but right now there is no time to wait, and we have to depend on the various machine hire companies needing a 'training course' to have much hope of getting a road-rail machine in to help us... If we have to PAY - it costs well in excess of £1 per minute plus delivery/removal lowloader costs....

[mobylette]

3/4 inch is the recommended free play[frame][/frame]

[bmcecosse]

Seems a lot to me !

[Boomlander]

I read with great interest the MMOC simplified method of removing the master cylinder by levering the torsion bar slightly to allow the cylinder mounting bolts to be drawn out and then refitted from the other side with the securing nuts now next to the torsion bar.
A much better option than removing the bar altogether!

[bmcecosse]

Of course - but when you put the bolts back - make sure they are not near or touching the T bar! You may need to shorten them slightly - or perhaps a thick washer under the head of the bolt will do the job.

[Boomlander]

Good point - thanks for the info Roy.

[les]

Of course the other option is to fit them the proper way!

[bmcecosse]

If you find it easy enough to lever the T bar out of the way, then yes !