Went to go for a Friday Night Burger Cruise with fellow VW’ers last night but had a few issues. After about 15 kms after leaving work, car slowed. Was like brakes were on. Pedal had firmed up. Pulled over and yes, front’s especially were hot. So we’re rears. Waited for mate and considered calling a tow and go home. Anyway, 20 minutes later all was good so carried on. The 20 odd Km drive to meet was fine. The 20 odd km to joint was fine. But coming home on freeway you could feel it slowing again as the pedal firmed up again. Got off freeway, and by that time fronts were smoking and rotors had a glow. Called a tow. By the time he pulled up (30 minutes?) all was good again. When motor was done earlier this year/late last year, new hoses and one way valve on booster went in. When I bought it a couple of years ago new brakes went on and fluid flush. Master cylinder and booster look to be original. I’m thinking master cylinder. Any other pointers before I get into it?
Have you got the necessary small amount of slack in your master cylinder pushrod? If it's not there, fluid can't return after applying the brakes...so they stay applied.
Pedal is in the up position. Somehow the pressure is building up. When it’s ok my normal travel comes back.
My guess would be a sticking caliper OR collapsed flexi , heating up the fluid and expanding everything . I've always been sceptical about the collapsed flexi theory but lord @CollyP had an issue with his front left so changed the caliper but no better , changed the flexi and job done Did it pull to one side at any point ?? Sent from my SM-G960F using Tapatalk
If it pulled to one side, I’d go with ^^^ what Mr Lasty is saying with regards to the flexi pipe. We re all very well aware that repro parts may not last the duration of this conversation . If there’s no one sided pull, I’d be back to checking the play available in your master cylinder, maybe that has somehow changed as it’s bedded in. Ozziedog,,,,,,,,,, Just thoughts out loud Barry mate
Similar scepticism here and I kick myself for not doing an autopsy on the one that I had an issue with. So if anyone on here has this issue in future, please do the necessary. I’ve also wondered if it could be grit / carp that has wedged itself into the internal wall of the flexi but pressure one way can get past, perhaps pushing the grit further down the flexi. Ozziedog,,,,,,,,,, But again ,, the new flexi worked
Servo gunked up with rusty water? Seen that a couple of times. Worth checking that the pedal doesn’t creep down when the engine is running
I have nothing to add other than it will be a process of elimination, but I noticed you said this earlier When motor was done earlier this year/late last year, new hoses and one way valve on booster went in Was the valve German or made of chinesium?
If the one way vacuum valve fails, that tends to lose the servo as no vacuum to assist, rather than jam the brakes on. My guess is either the brake pedal push rod adjustment was marginal and now some wear and tear has just taken it over the limit, or the servo has failed.
Check the push rod free play but odd for it to start out of nowhere... Sent from my SM-G960F using Tapatalk
It's more simple than than, they swell up and block. Pedal pressure forces the fluid through to the caliper but there is no pressure to return it the other way, not even a spring like the rears have.
NO!! but they look great hung on the garage wall. Ozziedog,,,,,,,,,,getting ready for a Stella athon,,,Caldicot Castle
The ferrules on the front hoses are shorter than stock, meaning you either have to bend the L-bracket in the arch, or make up new solid pipes in order to join them. Was like that in the set I fitted.
