Brakes breaked

[Baj]

At the weekend I changed my front pads.
I took the wheel off
Removed the spring
Undid the caliper slider bolts
Lifted out the floating caliper
Compressed the piston back in
Put on new pads
Refitted

Now they feel like they have air in them. Pedal stops about half way down then sinks slowly to the floor (with foot pressure on).
I bled the front but no visible bubbles came out. It still feels the same

I have been changing my brakes for nigh-on 20 years. I am no expert but I do know what I am doing. So the question is; what am I not doing?

[jonno12]

could be a stubbun airlock i know when i did my renault last year i took ages in the end i took it to the garage around the corner and they used a compressor bleeding tool they had

[Baj]

Yeah, I spoke to my local and he said by the time they ramp it up and get a monkey on it it will cost me £30
I may have to suck up and stump out

[jonno12]

not good mate i hade to have mine in the garage today on of the calipers was sticking on thats gonna cost me £30 today aswell all because i cant be ars eed top do it myself plus they have to re mot after but at least you will have piece of mind

[princepugh]

£30 for safe brakes sounds like a bargain to me! :-)

[jonno12]

i dont like messing with brakes on fast cars

[wegal]

Hmm could also be a leaking master cylider. Thats normally a sign of sinkage on the pedal, pump up the brakes with the engine off till you get a solid pedal, then with foot hard on brake pedal turn engine on, pedal should sink to a point and then stay solid, if it goes solid and then sinks my money is on master cylinder, if it just keeps going down then probably just air in the system, you can get a pressure bleed kit from halfrauds that you connect to the spare tyre and then bleed through, can some time takes a while, I had a landrover that used nearly a litre of brake fluid to clear the air lock. Start from the wheel farthest away from the resoviour and work forward.

[S60-MBS]

did you put the spring back in the right way..sounds like what i did once.

[Baj]

I should point out that the brakes where fine before I did the pads. A bit too coincidental for the master cylinder to start leaking now. Besides there are no obvious drips.
I dont think the springs can go in the wrong way round.

£30 isn't much for safe brakes but it is a lot when you are skint.

[v70torslanda]

Not Gospel but I have been told that modern thinking is to crack the bleed valve on the caliper and pump the fluid out through the bleed valve when you push the piston back. This prevents a reversal of pressure through the abs pump and dirty fluid being pushed back into the master cylinder.

When did you last change your brake fluid, Baj? Might be worth a shot.

J

[t5 pete]

buy a one person bleeding kit

[mikej]

Should not push piston back unless you crack open the nipple first due to the already mentioned ABS issue , another way to bleed as it sounds like an air lock to me is simply fill the master cylinder pot keep an eye on it and don't let the level drop too low and leave the lid/top off , fit bleed tube to nipple and simply let fluid drip into jar or similar , no need to pump the pedal just leave gravity do its bit , leave it drip for a while and then work your way around the car tightening each nipple as you work your way around , topping up the master cylinder pot as to keep the level from dropping too low . When finished pump the pedal untill brakes are hard and then fit top and try !
mike.....

[Alan M]

Hmm could also be a leaking master cylider. Thats normally a sign of sinkage on the pedal, pump up the brakes with the engine off till you get a solid pedal, then with foot hard on brake pedal turn engine on, pedal should sink to a point and then stay solid, if it goes solid and then sinks my money is on master cylinder, if it just keeps going down then probably just air in the system, you can get a pressure bleed kit from halfrauds that you connect to the spare tyre and then bleed through, can some time takes a while, I had a landrover that used nearly a litre of brake fluid to clear the air lock. Start from the wheel farthest away from the resoviour and work forward.

I'd go with this diagnosis.

[readview]

It does sound like you may have used a bit to much force squeezing the pots back and damaged the master,it's easily done and it is always best to push the caliper back with the nipple released.

[Redbrick]

Bloke on the VOC had this problem a while ago- turned out he hadn't put the springs back on the caliper properly. Also when I did mine they took an age to bed in to being anywhere near acceptable. My brake pedal drops to the floor if I press hard enough- a characteristic of the V70/S60 I'm told.
Not saying you don't have a bigger problem but maybe not, I hope!

[Baj]

Hypothetically if it were the master (which I am pretty sure it isnt), What would be the diagnostic, the thing wrong and what would be the remedy?

[S60-MBS]

Bloke on the VOC had this problem a while ago- turned out he hadn't put the springs back on the caliper properly. Also when I did mine they took an age to bed in to being anywhere near acceptable. My brake pedal drops to the floor if I press hard enough- a characteristic of the V70/S60 I'm told.
Not saying you don't have a bigger problem but maybe not, I hope!

That was me Andy lol..problems sorted once springs put in right

[Baj]

All indicators are now pointing at incorrectly fitted springs.
I will check them in the morning.
If anyone with an S60 fancied spending a Sunday removing a front wheel and photographing their caliper I would be grateful.

[readview]

The thing wrong would be that the rubber seals inside the master were allowing fluid to pass them when you apply force to the pedal,instead of pushing all the fluid down to the calipers.This damage can occur if you push the calipers back with too much force.The only soloution to this problem is to rebuild the master or replace it.Hopefully it will be an easier problem to rectify but it is something to be borne in mind for next time.

Hypothetically if it were the master (which I am pretty sure it isnt), What would be the diagnostic, the thing wrong and what would be the remedy?

[Baj]

It was the springs. \o/

Judging by the threads in the VOC I am not the only one to succumb to this.
The reason as I see it is that the springs can be fitted relatively easily in a secure and logical way that pulls the caliper down onto the bracket when what it needs is to be fitted in a really difficult and illogical way that stops the caliper rising from the bracket.