Brakes do not bleed! I have no brakes i need them back!

Ok, iv'e come to a point where i just don't know what to do!
I've brought a new master cylinder thinking it will cure the problem but no the same problem.
Only 2 channels of the master cylinder pump fluid normally which is the top end (facing towards the grille or front of car) but the rear 2 channels dont pump fluid like they shud, the bottom rear pumps ever so slighty of fluid and the rear left doesnt pump any fluid at all, this happened with my old master cylinder and it happens with my new one that i got from GSF today. I know for sure it isn't my brake lines because ive removed them from the cylinder to see if fluid is squirting out of the cylinder, and 2 wern't which are the ones im having troubles with. I've thoroughly cleaned the resevoir so its not dirt stuck, (the holes on the resevoir are big anyways so its pretty hard to clog it up). I tried to bleed the brakes normally and only two brakes bleed (front left and rear right) but front right and rear left don't do anything!

I so badly need help on this one because i have no breaks! And ive just freshly rebuilt my 1300 driver engine but i have not fired it up yet due to no brakes! (i need to drive it as soon as its fired up to put load on the engine to wear the rings in)
Help please!

BiG_J said

Only 2 channels of the master cylinder pump fluid normally which is the top end (facing towards the grille or front of car) but the rear 2 channels dont pump fluid like they shud, the bottom rear pumps ever so slighty of fluid and the rear left doesnt pump any fluid at all

Does this occur when the brake lines are disconnected from the master cylinder?

Also, are you refitting a standard master cylinder / servo or are you upgrading them to GTI spec or anything else?

Rich

mcscrew said

BiG_J said

Only 2 channels of the master cylinder pump fluid normally which is the top end (facing towards the grille or front of car) but the rear 2 channels dont pump fluid like they shud, the bottom rear pumps ever so slighty of fluid and the rear left doesnt pump any fluid at all

Does this occur when the brake lines are disconnected from the master cylinder?

Yes.

Also, are you refitting a standard master cylinder / servo or are you upgrading them to GTI spec or anything else?

I am refitting the standard spec ones, i took it apart in the first place to clean my engine bay and servo etc, while i was at it i emptied all the old fluid from the resevoir and gave that a clean too. After i refitted the servo/master cylinder i didn't bleed the brakes i left it for a month as the car was offroad and no engine in it, but just the other day i decided il bleed it as my engines in there now, at first i thought it was master cylinder fault so i brought a new one yesterday fitted that one and the same thing still happens. I am really confused as u can imagine, i really need help!
Cheers.

mcscrew said

BiG_J said

Only 2 channels of the master cylinder pump fluid normally which is the top end (facing towards the grille or front of car) but the rear 2 channels dont pump fluid like they shud, the bottom rear pumps ever so slighty of fluid and the rear left doesnt pump any fluid at all

Does this occur when the brake lines are disconnected from the master cylinder?

Also, are you refitting a standard master cylinder / servo or are you upgrading them to GTI spec or anything else?

Rich

Does this occur when just one of the rear (on the master cylinder) brake lines is disconnected at the MC? If it does, you have a faulty one…

paul_c said

mcscrew said

BiG_J said

Only 2 channels of the master cylinder pump fluid normally which is the top end (facing towards the grille or front of car) but the rear 2 channels dont pump fluid like they shud, the bottom rear pumps ever so slighty of fluid and the rear left doesnt pump any fluid at all

Does this occur when the brake lines are disconnected from the master cylinder?

Also, are you refitting a standard master cylinder / servo or are you upgrading them to GTI spec or anything else?

Rich

Does this occur when just one of the rear (on the master cylinder) brake lines is disconnected at the MC? If it does, you have a faulty one…

Happens when both rear lines are disconnected.

BiG_J said

paul_c said

mcscrew said

BiG_J said

Only 2 channels of the master cylinder pump fluid normally which is the top end (facing towards the grille or front of car) but the rear 2 channels dont pump fluid like they shud, the bottom rear pumps ever so slighty of fluid and the rear left doesnt pump any fluid at all

Does this occur when the brake lines are disconnected from the master cylinder?

Also, are you refitting a standard master cylinder / servo or are you upgrading them to GTI spec or anything else?

Rich

Does this occur when just one of the rear (on the master cylinder) brake lines is disconnected at the MC? If it does, you have a faulty one…

Happens when both rear lines are disconnected.

No I mean if the front ones are connected and the rear(s) are disconnected).

Iv'e not taken the fronts off, i know they work because theres fluid commin from the brakes (front left and rear right wheels) so yes it happens when both front is on and both rears are off. It does'nt make sense to be faulty because the old one did the same exact thing no difference whatsoever hence why i brought a new one.

Maybe there's a blockage on the reservoir?

I've check all of that, if you take the resevoir off you will see the holes they're at least 3.5mm big, its pretty hard to clog it up, besides ive fully cleaned it with water and let it dry so no water remains, im also using new rubber seals that go between resevoir and cylinder (came with new cylinder).

Now do you see why im confused?

If the front (from the MC) pipes are connected and all hydraulically sealed up, there's a clean reservoir fitted and topped up with new fluid, and you disconnect (could just loosen) one of the rear (on MC) connections and it doesn't leak or pump brake fluid out, then its a faulty MC.

paul_c said

If the front (from the MC) pipes are connected and all hydraulically sealed up, there's a clean reservoir fitted and topped up with new fluid, and you disconnect (could just loosen) one of the rear (on MC) connections and it doesn't leak or pump brake fluid out, then its a faulty MC.

It leaks but doesnt pump, one pumps very little amount of fluid, runny shall i say (rear bottom) and the other doesnt pump anything at all but leaks a little bit (front left).

Kinked pipe?

You need to buy a pressure bleeder like this one

http://www.mgocaccessories.co.uk/acatalog/Gunsons.html

By using a push method all you are doing is causing wear to the original master cylinder . Pressure bleeding will cure your problem , follow the instructions .

Nah, you need to avoid the pressure bleeder - in fact I think its part of the problem. There's probably a load compensator valve on the rears, which means that the lousy 20psi or so of the pressure bleeder doesn't really push the fluid through this that well, making it very slow and possibly not even bleeding the rears properly.

I use steady strokes on the pedal to around 70% of its travel. And, if the MC fails, I'd rather it fail in the workshop than during an emergency stop!

Right, 2 different opinions!
I was using 2 man method from start to bleed as i don't have that eazibleed thingy.
Who agrees or had personal experience of what im having and solved using eazibleed?

Or who agrees with paul_c?

BiG_J said

Who agrees or had personal experience of what im having and solved using eazibleed?

Me .

Let's see how it goes, then!

PS the 2 man technique is not so good, you really want to put a one way valve onto the bleed nipple.

paul_c said

Nah, you need to avoid the pressure bleeder - in fact I think its part of the problem. There's probably a load compensator valve on the rears, which means that the lousy 20psi or so of the pressure bleeder doesn't really push the fluid through this that well, making it very slow and possibly not even bleeding the rears properly.

I use steady strokes on the pedal to around 70% of its travel. And, if the MC fails, I'd rather it fail in the workshop than during an emergency stop!

Quote from the VW Bible

DO NOT pump the pedal using the old push method to to bleed the brakes on your car . You will push the master seals in to the unused portion of the cylinder and may induce wear or pick up dirt and ruin the seals . Use a simple low pressure bleeder follow the instructions and save on the cost of a new master cylinder . This also now has the advantage of being a one man task .

chudd said

paul_c said

Nah, you need to avoid the pressure bleeder - in fact I think its part of the problem. There's probably a load compensator valve on the rears, which means that the lousy 20psi or so of the pressure bleeder doesn't really push the fluid through this that well, making it very slow and possibly not even bleeding the rears properly.

I use steady strokes on the pedal to around 70% of its travel. And, if the MC fails, I'd rather it fail in the workshop than during an emergency stop!

Quote from the VW Bible

DO NOT pump the pedal using the old push method to to bleed the brakes on your car . You will push the master seals in to the unused portion of the cylinder and may induce wear or pick up dirt and ruin the seals . Use a simple low pressure bleeder follow the instructions and save on the cost of a new master cylinder . This also now has the advantage of being a one man task .

Book's wrong LOL.