brake problem - UPDATE

Need technical Q/A then you're in the right place

Moderator: martauto

Post Reply
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Mon Feb 16, 2009 8:25 am

on my drive back from wales last night, i noticed the car was pulling to the right a bit. i tried heavy breaking and it seemed to correct itself.

when i got home, i felt the brake disks and the drivers side was cold but the passenger side was real hot (burnt my finger).

i'm gonna look at the pads tonight and see what they are like but the disks are neither scored or ridged on the shiney surface.

what else do i need to do or look out for?
Last edited by no2lurch on Mon Feb 16, 2009 7:08 pm, edited 1 time in total.
DHFiS
Old Skooler
Old Skooler
Posts: 2733
Joined: Sat Aug 12, 2006 11:00 pm
Location: cambridge

Mon Feb 16, 2009 8:29 am

Seized caliper?
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Mon Feb 16, 2009 8:40 am

i thought that. can i cure it or do i need a new caliper?
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Mon Feb 16, 2009 8:49 am

just had a thought... could the hot side be siezed?
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Mon Feb 16, 2009 7:18 pm

well i got home and had the front in the air. started with the passenger side.

the wheel did turn but took some effort. it was not able to turn and then let spin a bit, it stopped as soon as i stopped turning it if that makes sense. i took the caliper off to find the sliders acting as they should with no resistance at all and the pads have plenty of life left and the disks are very good stil. to be honest they look fairly new. with the pads out i pressed the brake pedal a few times and the piston came out as expected. i had to use quite some force with the c-clamp to get them back in. with them all the way in, i reassembled and pressed the pedal again until it stopped going to the floor. tried to spin the wheel again and it was as i found it.

i then went onto the drivers side and found the wheel spin freely. did the same as with the pass side and all seemed freer. less effort was needed with the c-clamp and after reassembly, the wheel still turned freely.

so it would seem the passenger side is going on ok but not releasing. the dirvers side seems fine. so do i need to change the passenger side caliper?

do i need to change both sides? i'm worried the new side will show the old side up as not working as it should.

if i change caliper/s can i keep the pads and disks?

any other things to be wary of?
User avatar
gingebmx
E30 Zone Newbie
E30 Zone Newbie
Posts: 83
Joined: Sat Aug 30, 2008 11:00 pm

Mon Feb 16, 2009 9:35 pm

Hi Ive just changed my drivers side on my 325 sport as it was sticking as yours is, £50 odd quid from GSF (recon so had to give them old caliper) I also was a bit worried that on new caliper might cause problems. I have taken the car up the road with new caliper and the same pads and discs etc and it feels fine brakes dead straight and not sticking yey! Mine didn't get driven far whilst sticking so I would check if the wear is fairly similar on both sets of pad/disc combinations, also check the pad friction material hasn't cracked from the heat, the crack will be quite noticable. Obviously make sure if refitting the pads and discs that they are in the same order they come off and have a good look to be sure they are not knackered but I dont think they will be too bad. If in doubt ask mate
Chris
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Mon Feb 16, 2009 9:49 pm

which type of caliper do i have? its held onto the bracket 13mm bolts...
User avatar
gingebmx
E30 Zone Newbie
E30 Zone Newbie
Posts: 83
Joined: Sat Aug 30, 2008 11:00 pm

Mon Feb 16, 2009 10:11 pm

Mine is on 6mm allen key sliders its an ATE caliper, mines an early one. Check the caliper seal if you are wondering what may have caused the seizing mine was slightly miss seated and I guess some sh*te got in the caliper piston assembly. You could release the bleed nipple and see if it is easier to release, if so the brake line may be blocked but its a long shot,
Chris
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Mon Feb 16, 2009 11:25 pm

to get the piston out required no more efforrt really on the pedal... think i'll just get a new caliper and put it on. i'm just worried that the new caliper will show up and inadequacies in the origninal one on the other side. i heard they should be changed as pair.
Martinaston
E30 Zone Addict
E30 Zone Addict
Posts: 3749
Joined: Mon Mar 14, 2005 11:00 pm
Location: London

Tue Feb 17, 2009 12:15 am

You didn't mentioned if you have an ABS system so i'll assume you havn't got one.

Pull the caliper off the disc and pump the pedal so the piston moves out, leave the pads in so you don't pop the piston all the way out.
While its out chheck the condition of the rubber dust seal around the piston for holes/integrity and then fold it back and have a look at the condition of the chromed outer surface of the piston.
If water has got at the surface of the chrome plating, cracks and flakes will form and damage the inner pressure seal and jam the piston.
If the piston is ok you can buy just the seals instead of a whole new caliper.

Thats assuming you've checked its not a sagging/sticking pedal and thats the shortest pipe from the master cylinder to the wheel so the one most likely to show signs of pedal travel.
There is NO nucleus.
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Tue Feb 17, 2009 8:06 am

it does have abs
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Tue Feb 17, 2009 8:45 am

Martinaston wrote:You didn't mentioned if you have an ABS system so i'll assume you havn't got one.

Pull the caliper off the disc and pump the pedal so the piston moves out, leave the pads in so you don't pop the piston all the way out.
While its out chheck the condition of the rubber dust seal around the piston for holes/integrity and then fold it back and have a look at the condition of the chromed outer surface of the piston.
If water has got at the surface of the chrome plating, cracks and flakes will form and damage the inner pressure seal and jam the piston.
If the piston is ok you can buy just the seals instead of a whole new caliper.

Thats assuming you've checked its not a sagging/sticking pedal and thats the shortest pipe from the master cylinder to the wheel so the one most likely to show signs of pedal travel.
i re-read this at work and i have a few comments/questions...

the rubber dust shield is very dry and not so supple but i saw no signs of cracking as such.

what do you mean by this pedal travel? the pedal is at the top of its travel and stays there and there doesn't seem to be any sort of 'press the pedal a bit untill it does anything' type affair.

i'll be checking the pads more closely when i get home after work and also for this pedal travel thing if you could fill in my blanks before this...

i'm also worried its the abs system now too since its been mentioned.
User avatar
harry_p
Engaged to the E30 Zone
Engaged to the E30 Zone
Posts: 5313
Joined: Thu Oct 12, 2006 11:00 pm
Location: norfolk

Tue Feb 17, 2009 11:51 am

if it's only £50 for a recon calliper it makes no sense to have to bugger around with seals etc.

old one off, new one on, bleed it, job done.

if it bothers you that much that ones side will be newer than the other, do both and be happy that neither will need doing for another 20 years or so.
cheers,

harry
User avatar
no2lurch
E30 Zone Camper
E30 Zone Camper
Posts: 1487
Joined: Tue Feb 05, 2008 11:00 pm
Location: Cannock, West Mids

Tue Feb 17, 2009 11:57 am

thansk for the reasurrance. i'll doe the pass sied and see how it goes. i can do the other one at a t a later date.

one more question... if i change just the one caliper, do i need to bleed all 4 corners?
User avatar
georob
E30 Zone Camper
E30 Zone Camper
Posts: 1106
Joined: Thu Feb 03, 2005 11:00 pm
Location: Aberdeenshire

Tue Feb 17, 2009 12:43 pm

Should be able to free them up yourself, plenty wd, seal kit, sorted.
E34 x 1 - V8 + lots of CF
E30 x 2 - Tourings (1 x M50, 1 x M40)
RS6 C5 - Stage 1 remap - 500bhp

George
User avatar
gingebmx
E30 Zone Newbie
E30 Zone Newbie
Posts: 83
Joined: Sat Aug 30, 2008 11:00 pm

Tue Feb 17, 2009 7:12 pm

Yeah I thought about going that route but decided to let someone else do the work!

I just bled the fronts but if yours havent been done for a while bleed the lot, start from the furtest wheel from the master cylinder
Post Reply