How to solve a brake fade issue

[Veritas]

2003 VY Berlina Wagon, 5.7l

Whilst driving on a quite hot day I suddenly lost brake pressure. Bad brake fade with pedal going all the way to the floor. Just managed to get home. Next morning when cold brake pedal was back to normal.

Master cylinder showed pretty dirty fluid and black rubber seal in lid was thin and had a tear or two. Decided to replace master cylinder with a new Protex one myself. After installation have been trying everything to bleed them but no luck. Took car for a short drive, activated the ABS a few times to try and force any air out of it. Bled brakes again, but still no luck.

Took car to local garage down the road. They could not bleed it either and said they need more time to trouble shoot. Cannot wait for them as they have a 2 weeks waiting list. I am suspecting the ABS unit? What else could it be? Can I bypass the ABS by using a clear tube to bridge from the master cylinder lines to only the two front wheels? Of course will need to clamp securely with cable ties or something (just to see if I can get the pedal hard again).

Any thoughts?

Thanks in advance.

 

[Immortality]

A new master cylinder needs to be bench bled before fitting or you will struggle to get all the air out.

 

[rambunctious]

As immortality said, must be bench bled.
Leave it on the car and with the engine off, tap the brake pedal half a flyshit constantly.
Half a flyshit is small and light.
You might just get away doing it this way, I have.

 

[rambunctious]

[QU

 

[vc commodore]

Or with it on the car, get some old brake lines, and fit them up, with the old brake lines clamped shut....Leave one port open at a time, with an open brake line so you can bleed it that way.

Oh and catch the fluid coming out of the master cylinder

 

[greenacc]

Could you just disconnect 1 line at a time and bleed that one, then reconnect it and remove the next until all done?