Help....brake problem

[craftycarper]

Can anyone shed any light on my brake problem, series 3 front brakes. It failed the mot on a sloppy pedal, i've put a new master in and the brake pedal is nice and high, problem is now the front drums have locked up and i can only get them off if i undo the bleed nipple. It has new flexi hoses,shoes and cylinders all round and the master i have just changed but it seems that when you hit the brakes they are not releasing afterwards, i've only got a couple of days left to get it back down for a retest and its starting to **** me off

[edy]

i no someone might correct me, but all i canthink of is seized pistions to an extent, or sean as you say it only releases when the bleed nipple is released, a block in the pipes, dirty brake fluid with rubbish in possibly??

[craftycarper]

all 4 cylinders are new + the master, just stuck £7 worth of clean fluid through it, when the old naff master was on it the other day they were releasing...its doing me head in

[Rich_P]

If this was not a problem before you changed the master cylinder, then I think you have incorrectly adjusted the new master cylinder.  What I believe will be happening is that the pedal is at the end of its upwards travel, and the master cylinder piston has not retracted fully and therefore will restrict the flow of fluid back up into it.

Adjust the pedal with the two nuts on the master cylinder pushrod shaft accordingly until you get the pressure to release as it should.  I can dig out the pedal distances for the Series 2A but I do not think it would be applicable to Servo-assisted later Series 3 brake masters.

[craftycarper]

Ah ha, that sounds like a possibility, its a non servo by the way....so how do i go about adjusting the master then...idiots guide please

[Rich_P]

Take the cover plate off the top of the pedal box.  In there you will see the pushrod with two nuts towards the end and the pedal lever will be between these two nuts.  You simple wind the nuts apart and then wind the lead nut up or down the pushrod to the desired location.  Wind the trailing nut up tight against the pedal lever and there you go.  :dance:

[craftycarper]

cheers mate, i can tell you at the moment that the outside nut is at the end of the pushrod, the end towards the front of the motor which is where it was originally i'm guessing that this is wrong and it should be at least half way down the rod towards the bulkhead

[Rich_P]

On mine I think I moved it up about 1/4 of the rod.

[Les Henson]

I agree with Rich P - the rod is adjusted too tight. This will prevent fluid from returning to the master when you take your foot off the brake pedal. The brakes will wind up and lock. With your foot off the pedal, the rod should be slightly loose. Fiddly job to adjust the thing though.


Les.

[craftycarper]

sorted now mate, as you said though, fiddely little job...