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help with brakes
Posted: Sun Mar 02, 2008 12:37 pm
by dougie700
hi all,
Her who must be obeyed's moggy went in for MOT yesterday and failed!!
1. rear axle loose - now sorted
2. nearside rear brake recording little or no effort
3. nearside rear parking brake recording little or no effort
The MOT man said that it will prob be the drum, needs adjusting or shoes replacing. my question is how do i adjust them? i know there is an alen key type screw but which way do i turn it?
Thank you in advance
Dougie
Posted: Sun Mar 02, 2008 12:42 pm
by aupickup
hi it is a slotted screw, on the back 1 cylinder per side and on the front 2 cylinders per side
to tighten turn screww clockwise until brake drum doesn`t move then adjust back one notch
handbrake off
Posted: Sun Mar 02, 2008 12:51 pm
by alex_holden
Take the wheel off, release the handbrake, and remove the plug in the face of the drum (if fitted). Shine a torch through the hole and turn the drum until you see what looks like a large screw with a slot head. Turn it anticlockwise to slacken it off. Undo the two Phillips screws that hold the drum to the hub and pull the drum off.
Check that the shoes are completely dry. You might find that they're covered with either brake fluid from a leaky cylinder seal or gear oil from a leaky hub oil seal. Wipe out any dust with a damp rag, then throw the rag away (old shoes contained asbestos). Check that there's 1mm or more of friction material left on the shoes.
After rectifying any problems you find, put the drum back on and screw it to the hub, then tighten the adjuster up as far as it will turn, then back it off one click. You should now be able to turn the drum by hand. It may scrape a bit - don't worry about that, as long as it's not very difficult to turn. Put the dust plug back in, and reattach the wheel, making sure the indentation in the wheel lines up with the plug so it doesn't push it inside the drum. Spin the wheel by hand and get an assistant to try the handbrake and the footbrake. Make sure you can't turn the wheel when the brake is fully applied.
Posted: Sun Mar 02, 2008 1:20 pm
by bmcecosse
It's NOT just going to be adjustment! It will be seized (if lucky) or leaking cylinder. If seized then just a new cylinder needed - if leaking then also need new brake shoes - oily ones never recover. |Just a chance it's the rear axle that's leaked diff oil onto the shoes - then new seals + new shoes + check diff breather is not blocked. But overall - Good News if that's all that's wrong with the car - these are easy fixes.
Posted: Sun Mar 02, 2008 1:20 pm
by MoggyTech
Alex,
More detailed than the Haynes manual, nice one.

Posted: Sun Mar 02, 2008 1:59 pm
by dougie700
ok have taken the wheel off, there apears to be some fluid leaking from the hub

but just from 1 of the studs, could this really be causing a complete failure?
modern technology is brilliant, from the pics below, the brake shoes look good, and u can see the offending stud, how can i remedy this?
many thanks again to all posters

Posted: Sun Mar 02, 2008 2:04 pm
by dougie700
ps, i think the rear cylinder could be seized up as well

Posted: Sun Mar 02, 2008 2:05 pm
by alex_holden
They look OK. I forgot to mention the other possibility - the cylinder could be seized. Get somebody to push the brake pedal while you watch to see if it moves at all.
Posted: Sun Mar 02, 2008 2:06 pm
by alex_holden
dougie700 wrote:ps, i think the rear cylinder could be seized up as well

That's probably what is causing it then.
Posted: Sun Mar 02, 2008 2:15 pm
by dougie700
have had the missus press down on the footbrake no movement, there is movement wen the h/brake is applied and it releases ok, is it worth trying to re-bleed the system or just order a rear cylinder?
Posted: Sun Mar 02, 2008 2:19 pm
by aupickup
sounds like a seized cylinder
Posted: Sun Mar 02, 2008 2:23 pm
by dougie700
ok, i will admit defeat and trawl for spares lol
thank you all for your comments

Posted: Sun Mar 02, 2008 3:55 pm
by Orkney
Think a new cylinder is less than a tenner, if youve got the dosh you'd be as well to do the other side too. (always better to replace any brake components in opposing pairs)
That bleed nip looks a bit rusty - one or two if you do the other side wouldnt go a miss in case it snaps on the way out.
Posted: Sun Mar 02, 2008 4:50 pm
by MoggyTech
When you order the wheel cylinder, make sure to order the two copper washers that seal the banjo joint. Best to do both sides, or brake balance might be uneven at the rear, which is another MOT fail if more than a set percentage.
The tiny oil leak from the hub is common, and nothing to really worry about as the oil isn't getting onto the shoes.
Posted: Sun Mar 02, 2008 6:47 pm
by bmcecosse
You're in luck - it's just a seized cylinder. You could free it off - but then it would leak all over the shoes. New cylinder - and as others have said - may as well get two and treat the other side. However - it's highly likely the brake pipe will be a horror to unscrew - if so - new pipes from cylinder to T on the diff are a distinct possibility. But put a spanner on the pipes and see if they start to turn before ordering pipes - this may indeed be your lucky day!
Posted: Mon Mar 03, 2008 10:15 pm
by dougie700
hmm dont know about luck
replaced both rear cylinders today, now the 1 that was working before change aint and the 1 that did not work now does grrrrrr
looking at the shoes the one that does not work, shoes looked good, the one that was working the top shoe looked brand new and the bottom shoe nearly on the metal, should have got shoes while i was at Tom Roy's today.
The "old working side" does not adjust up now to grip the drum. also gonna need to replace the copper pipe between the three way banjo and the cylinder due to rounded nut
ps both the old cylinders worked fine off the car
Posted: Tue Mar 04, 2008 7:20 am
by Orkney
Sounds odd?
When you replaced them did you prime them? - the rears can trap air by the very design the bleed nipple wont allow it to come out.
In the upright position before fitting fill it with fluid using a syringe.
The uneven wear sounds very strange - make sure when you put the cylinders in to coppergrese the slot they sit in too which will help them work
Also what condition are the rubber boots on the outside in? Couple of pounds each would be worth replacing too if they are worn.
Whens the last time the brakes saw a service? looking at the thhe pics the underside of the car looks super clean yet the bleed nipple looks untouched for a long time.
Sounds like your going to get a good brake transformation once they are working correctly.
A good bleed through is to be reccomended, if youve had air in there then there migth be condensation in the fluid - what sort of state was the fluid in when you first bled it?
Good tip when you bleed - as well as the priming the rear cylinders - is to get the back of the car jacked both sides - if you have an upside down 'U' in the pipe from teh master to the T junction (this might be near the T) then VERY GENTLY bend it 90 degrees so your not left with an air trap.
This way your absolutely sure that theres not a great big air bubble there when you bleed.
Dont forget to bend it back when done.
You'll know when youve got it all working correctly - when they work properly they really are better brakes than people give them credit for as most aren't set up properly.
Posted: Tue Mar 04, 2008 4:08 pm
by bmcecosse
If you have fitted new cylinders - they MUST work!! The 0ld cylinders may work mechanically off the car - but I bet the inner hydraulic piston is seized in the old 'not working' cylinder. Be aware the brake pipes at that end of the car use 3/8" BSP connections - not the normal 3/8" UNF fittings. New shoes are always a good idea when fitting new cylinders - they cost so very little. And i've never had the slightest bother bleeding rear brake cylinders.
Posted: Tue Mar 04, 2008 7:46 pm
by dougie700
well replaced the cylinders, got away with the brake pipe by disconnecting it from the 3 way banjo,
went to the garage and re tried on brake tester, driverside fail this time...
got home opened up the hub and it was filled with axle fluid
cleaned up and put some instant gasket between the hub and the drive shaft - sorted, also put on the old Good cylinder and it seems to b ok now
yes i replaced the bleed valves, copper washers and rubber boots, wish i had bought the shoes while i was at tom roys, but such is life
brakes seem to be ok now so will go back to garage tomorrow for the retest.
bought 1 of those Eezibleed systems, had to drill a hole in an old master cylinder cap, flushed out the brake fluid.
took for sneaky test run and tried the brakes, schreeching rubber as i slammed to a halt

Posted: Tue Mar 04, 2008 7:48 pm
by bmcecosse
Hope for the best then !