[Brakes] No brakes

[newton1959]

So here we go, I have a 2011 Berlingo Multispace XTR and I suspect that we may have a problem with its brake master cylinder and before I subject my 70 year old arthritic joints to a few hours of pain trying to repair the problem I thought it would be a good idea to get some feedback from my fellow Berlingo owners.

Here are the symptoms.

1. The break pedal goes straight to the floor soon as the engine is started.
2. The brake fluid reservoir empties and again empties again when filled.
3. No sign of a brake fluid leak on any of the brake calipers and all pads and rotars discs are good.
4. The car exhaust smells different when running after the brake pedal has been pushed.

So what do you good and wise Berlingo owner think?

All advice and feedback happily received.

@newton1959 - It does have a brake booster / servo unit.

Here is the vac circuit in full: (might help)

Here is an update.... 

over the past few days I have had all the wheels of again and I eventually found a very small brake fluid leak in the rear right caliper (a small seal around the handbrake pivot arm) don't know how long it's been there ?. Bled the brakes, there was a little air in the rear calipers and near side front (left). I now have brakes, I topped up the brakefluid reservoir and took her out for a quick test. The pedal is quite firm and stops ???I will check the reservoir in a couple of days.

However I now have a permanent ABS light and brake warning light ?. Unfortunately my scan tool does not read abs faults but I have done a resistance test on all the wheel sensors and they all the same values on all the wheels and all the wheel speed signal generators look to be in good order no brakes or missing bits, all the sensors are clean and free of rust.

Any help or advice where to look next?

[deejay_xb]

if you have a hydraulic clutch then it uses the same fluid as the brake system, maybe the leak is from the clutch

[Sol]

Yes probably squirting the fluid out of somewhere, onto the exhaust. I'd get someone to press the pedal down to the floor while the engine is running, preferably warmed up, and look for fluid squirting and white smoke, with the bonnet up of course..

[newton1959]

if you have a hydraulic clutch then it uses the same fluid as the brake system, maybe the leak is from the clutch

Thank you automatic so no couch and no visible leaks

[newton1959]

Yes probably squirting the fluid out of somewhere, onto the exhaust. I'd get someone to press the pedal down to the floor while the engine is running, preferably warmed up, and look for fluid squirting and white smoke, with the bonnet up of course..

Thank you we have looked everywhere and it’s all dry with no visible leaks. I was wondering if it was possible that the brake fluid was leaking out the end of the master cylinder directly into the vacuum servo

[brodfather11]

Its a vacuum pump that powers the brakes on a diesel engine. Not enough vacuum for a servo as such in the inlet manifold. Mounted on the pass side of the engine driven of the camshaft
I would look at that .

(I'm assuming its a diesel?)

[newton1959]

Its a vacuum pump that powers the brakes on a diesel engine. Not enough vacuum for a servo as such in the inlet manifold.  Mounted on the pass side of the engine driven of the camshaft
I would look at that .

(I'm assuming its a diesel?)

Thank you for your response.
Sorry to sound thick but what should I be looking for that would cause the symptoms.

[Sol]

The vac pump provides the vacuum but surely there is still a servo drum, I have to look at mine. I assumed it had one and I'd be surprised if the vac pump drives the brake vacuum directly.

It is possible the brake fluid is getting sucked into the servo I guess, but I have never heard of that. No pedal due to buggered seals in the master cylinder, yes, fluid squirting out somewhere, yes but it has to be going somewhere, I agree.

Edit: just read a Google post where a mechanic found his car to be leaking brake fluid into the servo drum, so it is possible.

[ItsGreen]

Leaking into the servo isn't impossible.

My favourite method of looking for leaks is chuck a big sheet of cardboard under it and see what it looks like in the morning.

[newton1959]

The vac pump provides the vacuum but surely there is still a servo drum, I have to look at mine. I assumed it had one and I'd be surprised if the vac pump drives the brake vacuum directly.

It is possible the brake fluid is getting sucked into the servo I guess, but I have never heard of that. No pedal due to buggered seals in the master cylinder, yes, fluid squirting out somewhere, yes but it has to be going somewhere, I agree.

Edit: just read a Google post where a mechanic found his car to be leaking brake fluid into the servo drum, so it is possible.

Thank you for your persistence I think that I'll bit the bullet and order a replacement... but here is another dilemma... they have two versions with different size ports listed for our 2011 Berlingo Multispace XTR 1.6 Diesel HDI 90.. which one should I order ??? Why is it so complicated lol.
Has anyone any idea please.