Brakes Dilemma Update*****

[Dub Style 0]

Rite my car had had mk4 golf rear calipers fitted and im using corrado Pads. The problem i have is only the nsr wheel turns freely in air the os rear binds a little.

 

The fronts are the worst the n/s binds a little the o/s binds so bad that the disc gets red hot after maybe 2/3 km the car does not roll. I've taken the caliper off once before and gave the piston a clean and lubed it a bit worked for a little while but now its back.............wtf do i do car dont even roll on a sort of down hill. I was thinking of getting a new caliper what sort of prices am i looking at. Its a vr6 by the way

[gaz the geezer 0]

hello Dub Style, i assume the handbrake cables are releasing properly, you may have a sticky cable on one side, you dont say how old the calipers are, have you replaced them recently ?

[Toad 0]

you probably need to clean the sliding pins the calipers move on and lube them up with copper grease that will allow the calipers to slide easily and might help stop the binding, otherwise, the piston bores might be damaged or corroded.

[Dub Style 0]

The rears were fitted a year ago, the cables do seem fine. The front are originals of the car

[gaz the geezer 0]

there is every chance that if the front calipers dont respond to a bit of cleaning and lubrication then they may well be fooked, i`d be tempted to do the things that cost time rather than money first, the rears will probaly be ok with the same sort of treatment, have you replaced the brake fluid recently ?

[Dub Style 0]

yep had full new fluid in Nov

[gaz the geezer 0]

yep had full new fluid in Nov

 

excellent, give the calipers a quick pull apart and see what kind of condition there in, lubricate and put back, just out of interest, do you use the car regular and is it stored outside mate

[Dub Style 0]

Its used as a second car so not that often. what actually makes the piston go back when you take your foot off the brake is it pressure????

[_Monkey 0]

Like gaz said, I'd take them apart and give the sliders a gentle sanding and copper greasing.

 

Yeah, think it is the pressure that pulls back the piston.

[buttles 0]

I have some working front callipers and carriers off a VR if you need them.

[Dub Style 0]

******update******, took the rear caliper apart today and when i would turn the hand brake mech on the caliper the piston comes out but does not go back in. Could my problem be the fact that there is less pressure in the system hence the pistons in the calipers are not returning?, also if one or more of my abs sensors are down will the pump stop working

[Supercharged 2]

If one of the sensors is down then the ABS light will be on - this means the ABS is disabled

[Dub Style 0]

The brakes should still work okay shouldnt they

[Supercharged 2]

Yep, the brakes will work fine...

[Dub Style 0]

Do you know what makes the caliper piston spring back, is it fuid pressure?

[Supercharged 2]

I *think* it is just fluid but i'm no brake expert...

[buttles 0]

There is no 'returning' pressure as such. When you take your foot off the pedal the pressure dissipates back up through the master cylinder. The pistons then just sit where they are, not providing any force against the pads. The rear brakes also have the hand brake mechanism which through a cam type setup internally push the piston out when you pull up on the handbrake. As you have seen, when you move the lever on the end of the calliper the piston comes out and stayes out. That is normal as there is no disc and pads to stop the piston coming out. When people talk of seizing callipers it is the piston not being allowed to move back a little by the mechanical mechanism which causes the pads to be kept against the disc. Internal corrosion can also have the same effect by jamming the piston. Hope all that is not too full of bull!! Good luck.....

[Dub Style 0]

Fitted a new o/s caliper today, this side was sticking the worst. It all went together ok bled the caliper etc. The car rolls now much better but i'm still not convinced its sorted. when the wheel is in the air and you turn it by hand it will do one and a half rotation and then stop dont know if this is right but also you can hear a little sssss when you turn the wheel i dont know if i'm just being paraniod or what there is no visual gap between the pads and disc again dont know if there is supposed to be or not. and oh what do the little thin shim type things do that sit on the carrier front and rear when the pad sits in place???

[Kevin Bacon 5]

The shims stop squeal.

 

If the wheel binds mid rotation, sounds like a warped disc to me.

[billinjah 0]

yeah that has to a warped disc

[buttles 0]

Sounds like you have sorted it. Any new components will take a while to bed in and might cause a little drag in the brakes causing the 'ssss'. Just the pad rubbing on the disk. There will be no gap between the pads and the disk.

[buttles 0]

Bit of overlap there!! If you turn the wheel by hand does it drag at any particular spot?

[Dub Style 0]

Bit of overlap there!! If you turn the wheel by hand does it drag at any particular spot?

 

Not really no, the discs are brand new.

[buttles 0]

I would leave it for a bit and see how they are in a week or so