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Mon Mar 27, 2017 6:11 am

I'm 17 and I'm a student at a vocational school and I'm working on two VW's a 1973 VW Squareback and a 1979 VW bus so far I've had a fun time working on them and plan to do more. On the Squareback I'm having problems with getting pressure on the brake pedal I've bleed the brakes four times and I'm still not getting any pressure I have to pump the brakes three times just to get some pressure but its not alot. I have no clue what else to do so if anyone has any ideas for me that would be helpful and thanks for the help.

Mon Mar 27, 2017 4:30 pm

If you have no firm pedal without pumping, and no leaks, then there are three possibilities:
1) master cylinder has failed internally
2) one or more wheel cylinders have failed internally
3) one or more flexible brake lines have failed internally
There is probably no shortcut to a complete system disassembly and repair

One slight possibility... on VW dual-piston master cylinder systems (like yours), you have to bleed the fronts first, then the rears (the opposite of what many books say). This can be hard if the rear brakes are adjusted very loose. So tighten up the adjusters on the rear until the wheel can't turn, then bleed the fronts, then back off the stars and bleed the rears. Then adjust the stars and your e-brake.

Tue Mar 28, 2017 12:28 am

Also see Ray's reply in your teachers thread, as he explains master cylinders.

Phil is correct in that you bleed the fronts first on these cars (RF 1st), and if you're going to bleed the rears, get the brake adjusters tight, so you're only bleeding the wheel cylinders. After you get the air out of them, re-adjust the adjusters (helps to have the tire off the ground, so you can feel a very slight drag of the brake shoes against the drums). Also, when using the hand brake, it should only rise up 3 clicks to stop the rear tires. If it needs more than 3 clicks to stop the tires, then the cables need to be adjusted (under the E-brake boot inside the car).
I hope this helps.