handbrake and ABS problems

[nealo]

yeah i noticed it wasn't returning to its stop like the O/S does, but i gave it a good push at the weekend and its not going anywhere in that direction! i don't mind dropping it of at the garage. its on the way to work and i can cycle the rest of the way. would rather get it done by seat before the warranty runs out in July.

 

[RUM4MO]

All sorted now?

 

[nealo]

They are better thanks but not brilliant. According to the technician the offside cable was stuck. Both cables are now lined up under the ashtray. I was told that this fix wasn't covered by the warranty but that they'd done it free of charge anyway.
I'm not convinced that its as good as new though. The footbrake still travels quite a bit more than I feel it should, so it either needs a good bleed or there's something else wrong. I can still get the ABS to kick in but the distance the pedal has to travel seems excessive.
The pedal doesn't quite go to the floor before stopping - I can just get my other foot underneath it. If I stamp on the brake it is solid, but if I press it slowly it sinks. Is this a sign of air in the system? The pedal hisses quite a bit as its going down.
With the pedal pressed, the handbrake has at least another 2 clicks more than when the pedal is not pressed.
And with the engine off, if I pump the brakes til they are hard, there is still a tiny bit of "spongy" movement before the pedal stops moving (if that makes sense).
I was expecting the car to come back perfect, but I guess to take it to the garage a second time I will get charged.
Cheers for the interest.

 

[nealo]

They are better thanks but not brilliant. According to the technician the offside cable was stuck. Both cables are now lined up under the ashtray. I was told that this fix wasn't covered by the warranty but that they'd done it free of charge anyway.
I'm not convinced that its as good as new though. The footbrake still travels quite a bit more than I feel it should, so it either needs a good bleed or there's something else wrong. I can still get the ABS to kick in but the distance the pedal has to travel seems excessive.
The pedal doesn't quite go to the floor before stopping - I can just get my other foot underneath it. If I stamp on the brake it is solid, but if I press it slowly it sinks. Is this a sign of air in the system? The pedal hisses quite a bit as its going down.
With the pedal pressed, the handbrake has at least another 2 clicks more than when the pedal is not pressed.
And with the engine off, if I pump the brakes til they are hard, there is still a tiny bit of "spongy" movement before the pedal stops moving (if that makes sense).
I was expecting the car to come back perfect, but I guess to take it to the garage a second time I will get charged.
Cheers for the interest.

The car was in again today, and its now like new - just as i wanted it. The garage changed the brake fluid again (3rd time in 5 months) and it's spot on.

When i changed the brakes back in December I removed the cap from the reservoir to wind the pistons back in. I now realise that I didn't need to do this. The cap was off for a while and because the brakes were so bad afterwards I asked seat to do a fluid change, even though it was so soon after having had one carried out at the last service. Because of this I suspect the 2nd BFC wasn't carried out, hence why I wasn't charged for today's BFC!
Anyway, all sorted now.

 

[RUM4MO]

Great! Sorted at last, BTW taking and leaving the cap of would not add any if much more moisture into the system as the reservoir does have a breather hole - otherwise a low pressure zone would exist above the fluid in the reservoir as the brake pads and discs wear out.

 

[george130]

Slightly offtopic... Lately my handbrake has been a bit crap, and no amount of using the handbrake whilst on the footbrake seemed to help, so I did a bit of high-ish speed braking (Had a 312mm conversion 6 months ago if that matters) and the handbrake is nice and tight now

Does this mean something is sticking in my rear calipers?

 

[nealo]

Great! Sorted at last, BTW taking and leaving the cap of would not add any if much more moisture into the system as the reservoir does have a breather hole - otherwise a low pressure zone would exist above the fluid in the reservoir as the brake pads and discs wear out.

even if i left the cap off overnight?

 

[RUM4MO]

even if i left the cap off overnight?

No, not to any great extent, its more down to the fluid's ability to extract moisture from the air, as I said there will be (must be) an air vent in the cap and any craving that the fluid has for moisture will not be getting limited even by that small hole - probably its all down to water vapour pressure - ie a moisture gradient between the ambient air and the fluid in its present state. That is why, if you have a very dry volume filled with very dry gas, if this volume leaks, then in normal wet conditions, the ambient moisture will "back stream" against the pressure differance and try to equalise the moisture levels (or dewpoint) despite the real world pressure differances - that is the buggar of what is called water "vapour pressure"!

 

[RUM4MO]

Slightly offtopic... Lately my handbrake has been a bit crap, and no amount of using the handbrake whilst on the footbrake seemed to help, so I did a bit of high-ish speed braking (Had a 312mm conversion 6 months ago if that matters) and the handbrake is nice and tight now

Does this mean something is sticking in my rear calipers?

I'd hope that what you have done is a bit like an "Italian tune-up" - but to the brakes. It has been well documented that the rear brakes are normally grossly under worked, so doing a prolonged bit of high speed braking will have cleaned up all surfaces, a bit like stripping them down and cleaning them up before re-fitting! I'd have a look underneath to make sure the levers, when the handbrake is "off" are both sitting on or nearly sitting on their "off" stops.

 

[george130]

I'd hope that what you have done is a bit like an "Italian tune-up" - but to the brakes. It has been well documented that the rear brakes are normally grossly under worked, so doing a prolonged bit of high speed braking will have cleaned up all surfaces, a bit like stripping them down and cleaning them up before re-fitting! I'd have a look underneath to make sure the levers, when the handbrake is "off" are both sitting on or nearly sitting on their "off" stops.

Interesting stuff, cheers rum4mo!