Break bleed problem

[GPO_Van]

I've never had problems bleeding breaks before, but, the story, get into the car to move on drive, brake peddle down to floor wrench on handbrake as the front of the car decimates a line of Lavender.
Spotted fluid mark on the back tyre, take wheel of to find it is hypoid not brake fluid, fix gasket, take all wheels of in turn, front offside leaking cylinder, order 2 new slaves and fit.
The problem is that working around car I can never get a stream of bubble free fluid.
Friend then pumps down on pedal several time and with the system fully pressurised I can then bleed 3 pumps of clear fluid down tube then bubbles?
It must be the master cylinder, anyone agree? yet master cylinder has new rubbers and has only done about 20 miles around the local town and around my drive over the past 3 years since fitting.
Unless anyone thinks different, I'm going to buy A new master cylinder.

[oliver90owner]

Go ahead, but I think differently, for one. Think here, what is the probability of a slave leaking and the m/c going out at the same time?

[GPO_Van]

Oliver90
The odds are against it, yes, but also is the rear wheel gasket going at the same time!
But for the very reason you state, is why I decided to post the question, I normally find bleeding brakes with a competent person pumping when you say is easy.
I'm wide open to suggestions, even rude ones if it gets the car back on the road, thanks all.
Reg

[kennatt]

Its strange that you get three clear fluid bleeds then bubbles,if it was the master, surely there would be bubbles at every stroke,the air can only be drawn in on the return stroke at the master or the cylinders,and leak on the pressure stroke .Have you tried just getting the assistant to pump pedal hard and hold then open the bleed and close when he says pedal right down and held down. with you saying ok pedal up after you have nipped up the nipple. etc. ,it's possible the air is re entering at the joint of bleed pipe/bleed nipple. doing the above eliminates that joint.

[johngrigg]

Did you fit the new slaves with the bleeder to the top? I once went through 3 bottles of fluid trying to bleed calipers that I had swapped side to side resulting in the bleeders being at the bottom. Like you I'd never had a problem previously once the wife was properly trained......

[biomed32uk]

Well to stick my bit in here from my experiences....

I recently had my master cylinder out, and while it was out thought I would re seal it, having no history of when it was last touched.

The bore looked perfect, new seals fitted and all refitted to the car. The brakes bled OK, no bubbles where they shouldn't be and worked OK. Something however did not feel quite right, that moment when you sit with your foot on the brake at the end of the drive and think I am sure that pedal just dropped a bit.

By some jiggling on the brake pedal with my foot I could ultimately get it to go to the floor, not good. So it turned into a whole new master cylinder, which has been fine.

I use a vacuum bleeder on mine, I can do the whole car first time round in about half an hour and all on my own.

[GPO_Van]

Hi All
Have tried just getting the assistant to pump pedal hard and hold then open the bleed and close when he says pedal right down and held down, that produces less bubbles, but still a few, have driven round the block and brakes fine though, not spongy.
I have left the master cylinder cover off to check for leaks/loss of fluid.
Slave cylinders right way up, bleed at top.
If no leaks or fluid loss, and brakes do not go spongy I'll leave well alone, any hint of a problem I'll buy a full master cylinder.
Thanks all for your response, will let you know what transpires in a week or so.

[GPO_Van]

No problems, all working ok, have left the carpet off so I can regularly check the break fluid and there has been no loss.

[amgrave]

Break is spelt B-R-A-K-E, unless you mean you have broken it
Glad you seem to have it sorted now though, nothing worse than not knowing if you are going to stop OK