Brakes - Help

[David Lynch]

Right... Fitted new M1144's (Front) at the weekend (nothing really wrong with old ones, bite certainly improved but still needed a hefty boot). Noticed marking (like filing) on piston end (inner left) but figured that'd been there a long time. Rears inspected only.

 

Last night did the full bleed LR RR LF RF with my Easybleed Kit and was happy I'd pushed over a clean litre of fluid through (few specs of solids in the system, but remarkably few bubbles).

 

Test drive gave interesting results, braking front first but pulling right (FR always locks first being closest, correct?). Stoppers certainly effective and pedal feel great, but what happened next was a puzzle. If coming off brakes quickly car lurched right as if one brake still applied momentarily. Controllable with steering wheel thankfully.

 

Now I'm concerned - Sticky piston ? Any merit in removing a bit of fluid as at Max level? Basically, where do I go next ? I value my braking more than power (don't have much anyway ).

 

Any advice much appreciated....

Ta, David

 

1.4K SS 😬 here 'You've got be in it to lose it !'

[Sheds Moderator]

Sounds indeed like a sticky piston. I would get the piston out as far as poss and clean the sliding surfaces with fine wire wool and meths or brake fluid. Then back in. Any scores or damage - exchange caliper.

[susser]

My FR locks first as a rule. I don't think its a feature of being closest 'cos the dynamics of the fluid are such that pressure is distributed evenly. I think it's because there's less weight on that tyre as it's "up camber".

Actually, I find it's useful in only having to monitor one wheel during threshold braking.

Oh and yes, I agree; sticky piston.

 

Edited by - susser on 5 Jul 2006 10:57:28

[Normans_Ghost]

David. Try this.

 

Remove master cylinder cap and put clean cloth around cylinder as fluid mak overflow.

 

Remove outer pad. Insert two long screwdrivers and get someone to gently press pedal till piston is nearly squeezing screwdrivers. Off pedal and pull evenly on screwdrivers to push piston back in. Do this a few times till the piston moves in and out fairly freely. Then refit pad and do same with inner pad removed. Then do other side of car.

 

If a piston is badly scored and/or corroded it will leak. If it's not leaking and will move freely in and out then it's OK. If not exchange callipers.

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

You and your seven to The French Blatting Company Limited

[David Lynch]

Thanks all. Like the tip for working against minimal back pressure Norm

 

1.4K SS 😬 here 'You've got be in it to lose it !'