Itchy's brake issues part two

So I got the brakes bled and took Itchy for the MOT today (only one page of failure notes, not as bad as expected). I was a little late and had missed my spot but they had another in an hour. I was going to drive up to town for lunch but the brakes had locked on - it wouldn't roll down the slope and the pedal was pretty hard. I walked into the village for lunch and an hour later the pedal was back to where it was before (which was quite high) and the Landy rolled down the slope. MOT done, I drove the ten miles home and by the time I got home the pedal had gone hard again and the Landy wouldn't roll...

Have I just adjusted everything up a little too tight or could it be something else..?

have you got a servo?

Nope.

ok servos can pull brakes on if poorly adjusted , is your pedal over adjusted it could stop fluid returning to res

I'll try and under adjust it tomorrow and report back.

just out of intrest ,,you say you have replaced all the brake flexis ,,,did u put flexis on the rear ,and did u put the flexis straight to the rear cylinders ?

There is one flexi on the rear, near the diff, that serves both rear wheels.

have you got the brake shoe return springs fitted correctly

Iann said:

have you got the brake shoe return springs fitted correctly

Click to expand...

Yep.

I think the issue was bleeding the brakes whilst the system was pressurised and too much adjustment on the master cylinder. I've slacked off the master cylinder by a couple of turns and let out some brake fluid from the NSR bleed nipple. It'll need an extended road test to find out if it's done the trick and that won't be happening until we go for the retest next week.

Well, the system is still pressurising. I've screwed the adjusters on the master cylinder out as far as they will go (right to the end of the thread) and the system still pressurises after four or five applications of the brakes. If I release the pressure through any one of the bleed nipples it's alright for a little while.

I'mthinking that maybe I have another duff master cylinder... :mad2:

Dumb question and not sure from what I've seen here - you have the pedal adjusted so the master returns fully, right? There needs to be a space once the pedal is released and is at rest - at that point the pushrod should not be engaging the piston in the master but should have a space (1/8"IIRC).

Made this mistake once and had the same symptoms you describe here - piston was not returning fully so the system coudn't vent.

I know you talk about the pedal adjuster above, but were it me I'd be backing off the pushrod locknuts.
ajr

mrchurchill109 said:

Dumb question and not sure from what I've seen here - you have the pedal adjusted so the master returns fully, right? There needs to be a space once the pedal is released and is at rest - at that point the pushrod should not be engaging the piston in the master but should have a space (1/8"IIRC).

Made this mistake once and had the same symptoms you describe here - piston was not returning fully so the system coudn't vent.

I know you talk about the pedal adjuster above, but were it me I'd be backing off the pushrod locknuts.
ajr

Click to expand...

I wish I read this before (in a fit of peak) I took the MC out, again. Refitted the Bearmach one (which I thought was shot but isn't), bled it and adjusted it and all fine now.

Which way have you turned the adjusters? They need to be screwed towards the master cylinder until there is a bit of free play in the rod.