Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: tunnie on 04 June 2013, 13:39:39

Title: Uneven pad wear
Post by: tunnie on 04 June 2013, 13:39:39
Brake Warning came on for MotherT's Estate, stripped down to investigate & add new pads. But they have worn unevenly, so going to replace the discs too.

Now outside looks fine:

(https://dl.dropboxusercontent.com/u/803897/Omega/Wheels/2013-06-04%2012.46.35.jpg)

Pad looked ok on the outside:

(https://dl.dropboxusercontent.com/u/803897/Omega/Wheels/2013-06-04%2012.43.19.jpg)

But inside pad looked like this:

(https://dl.dropboxusercontent.com/u/803897/Omega/Wheels/2013-06-04%2012.43.58.jpg)

Disc...

(https://dl.dropboxusercontent.com/u/803897/Omega/Wheels/2013-06-04%2012.44.41.jpg)

Looks like drivers side disc maybe similar as the outside edge is corroded, put the old pads back for now. As I'll get some fresh fluid too, might as well as its due a change too.

But wondering why its worn so badly on one side? Would a sticking caliper not do it on the outside as well?  :-\
Title: Re: Uneven pad wear
Post by: b4ndit on 04 June 2013, 13:46:01
it could be the sliders are sticking, maybe in need of a good clean and grease the pins :y
Title: Re: Uneven pad wear
Post by: tunnie on 04 June 2013, 14:13:03
it could be the sliders are sticking, maybe in need of a good clean and grease the pins :y

Good point, will do that. They just pop out don't they?
Title: Re: Uneven pad wear
Post by: Doctor Gollum on 04 June 2013, 14:18:00
Could it be, that the pad got stuck on the inner edge near the hub? So as it wears and the piston moves out, that particular pad is leaning over...? Maybe? Or the pad was not seated correctly. :-\

But yes first thing to check is that the calliper sliders move freely. But you would have checked that I'm sure.
Title: Re: Uneven pad wear
Post by: tunnie on 04 June 2013, 14:19:46
move ok now, but could have got stuck, will grease them and also give caliper bracket a good clean
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 14:23:45
I can't see your pictures, but if they are anything like those I took of my car when I replaced my discs a couple of years ago, the outer face of each disc was almost perfect ( a few grooves, but nothing much) The inner faces though, were only worn on about a third of the surface leaving the rest covered in scale/rust
Title: Re: Uneven pad wear
Post by: tunnie on 04 June 2013, 14:27:12
I can't see your pictures, but if they are anything like those I took of my car when I replaced my discs a couple of years ago, the outer face of each disc was almost perfect ( a few grooves, but nothing much) The inner faces though, were only worn on about a third of the surface leaving the rest covered in scale/rust

Identical issue here  :)  :y
Title: Re: Uneven pad wear
Post by: henryd on 04 June 2013, 14:51:32
I can't see your pictures, but if they are anything like those I took of my car when I replaced my discs a couple of years ago, the outer face of each disc was almost perfect ( a few grooves, but nothing much) The inner faces though, were only worn on about a third of the surface leaving the rest covered in scale/rust

Identical issue here  :)  :y

The inside of the discs gets the splash from the other wheel therefore deteriorates faster :y
Title: Re: Uneven pad wear
Post by: 05omegav6 on 04 June 2013, 15:46:40
Often found that the inner pads wear first with that design caliper :-\ All three of my Mk3 Granadas were the same :y
Title: Re: Uneven pad wear
Post by: dbdb on 04 June 2013, 16:09:23
I can't see your pictures, but if they are anything like those I took of my car when I replaced my discs a couple of years ago, the outer face of each disc was almost perfect ( a few grooves, but nothing much) The inner faces though, were only worn on about a third of the surface leaving the rest covered in scale/rust

Me too, just had the front wheels off and inspected them  Outer disk shiny and smooth to the edge, inner surface only clean and shiny 1/2" in from the edge on o/s, 1 inch in on n/s (worse).  These brakes must have been like this last August when they passed an MOT no problem and I suspect they may do the same this year.  However the car judders under heavy braking from speed as you can imagine.

As the inside edge surface is rusty and rough and above the level of the shiny surface it's clear the pads don't ever  touch it.  So either the pads are missing some of their surface or they are being applied  to the part nearest the hub only. Is there any other explanation? 

As I never brake in my driving  :) it rarely bothers me and I'm reluctant to replace the disks but I suppose I must.
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 17:42:52
....
As I never brake in my driving  :)  .......

 :P Not another one that 'brakes' on the gearbox! It's great for the poor soul behind!  :-X  :-X
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 17:44:12
I can't see your pictures, but if they are anything like those I took of my car when I replaced my discs a couple of years ago, the outer face of each disc was almost perfect ( a few grooves, but nothing much) The inner faces though, were only worn on about a third of the surface leaving the rest covered in scale/rust

Identical issue here  :)  :y

These were mine. Surprisingly  ::) my brakes improved no end when I fitted new discs.  ;)
outer face
(http://i84.photobucket.com/albums/k17/Tiff4327/Omega/S73F0902.jpg) (http://s84.photobucket.com/user/Tiff4327/media/Omega/S73F0902.jpg.html)

and inner face
(http://i84.photobucket.com/albums/k17/Tiff4327/Omega/S73F0901-1.jpg) (http://s84.photobucket.com/user/Tiff4327/media/Omega/S73F0901-1.jpg.html)
Title: Re: Uneven pad wear
Post by: tunnie on 04 June 2013, 17:50:11
Yup exactly like MotherT's!
Title: Re: Uneven pad wear
Post by: tigers_gonads on 04 June 2013, 17:54:24
Tbh, I pull my wheels off every few months and abuse the discs and calliper's with Percy the lump hammer  ;)
Tends to break up any rust on the disc's any keep the calliper's free   :)

Great for stress relief too  :-X :-X :D
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 18:20:30
Tbh, I pull my wheels off every few months and abuse the discs and calliper's with Percy the lump hammer  ;)
Tends to break up any rust on the disc's any keep the calliper's free   :)

Great for stress relief too  :-X :-X :D

if the dust shield is in place, you can't see, let alone hit, the inner face  ;)
Title: Re: Uneven pad wear
Post by: dbdb on 04 June 2013, 18:35:01
:P Not another one that 'brakes' on the gearbox! It's great for the poor soul behind!  :-X  :-X

Nope, just don't brake at all.  Don't change gear much either.  Roundabouts can easily be taken at 45 in 5th  if you plan ahead. Traffic lights change if you anticipate. Pedstrians get out of the way if you don't show weakness ;)
Title: Re: Uneven pad wear
Post by: dbdb on 04 June 2013, 18:39:20
if the dust shield is in place, you can't see, let alone hit, the inner face  ;)

On my f/l V6 you can on the front, just checked mine today (remove the wheel though).  On the back it is fully covered but you can get a finger behind the dust shield by bending it (bend it back afterwards)
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 18:40:30
:P Not another one that 'brakes' on the gearbox! It's great for the poor soul behind!  :-X  :-X

Nope, just don't brake at all.  Don't change gear much either.  Roundabouts can easily be taken at 45 in 5th  if you plan ahead. Traffic lights change if you anticipate. Pedstrians get out of the way if you don't show weakness ;)

I'm glad I don't have need to drive around west London .............  :-X
Title: Re: Uneven pad wear
Post by: dbdb on 04 June 2013, 18:49:49
These were mine. Surprisingly  ::) my brakes improved no end when I fitted new discs.  ;)

Yes just like mine too.  In fact mine are a bit worse.    However looking at your photos it looks like the rusted surface, after the loose rust is gone, is below the level of the shiny.  I had assumed mine were the opposite, the rust protruding  and so was puzzled why the pads weren't hitting it.  Now I look at the photos I am thinking that what has happened is the brakes weren't used much in anger, the outer edges of the inner disks were subjected to more spray as henryd mentioned, so they rusted more.  Initially the rust was above the surface  but as it falls away the actual corroded solid surface is below the shiny, so is never again touched by the pads, and rusts some more. A vicious circlke

Makes sense now.  Not  braking hard enough or frequently enough.

Did you experience any juddering under hard braking?
Title: Re: Uneven pad wear
Post by: dbdb on 04 June 2013, 18:53:01
:P Not another one that 'brakes' on the gearbox! It's great for the poor soul behind!  :-X  :-X

Nope, just don't brake at all.  Don't change gear much either.  Roundabouts can easily be taken at 45 in 5th  if you plan ahead. Traffic lights change if you anticipate. Pedstrians get out of the way if you don't show weakness ;)

I'm glad I don't have need to drive around west London .............  :-X

Are you sure you haven't been round here on Sundays?  It does get noticeably harder to do then ;)
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 19:00:15
....
Did you experience any juddering under hard braking?

No juddering, just a p155 poor springy feel to the pedal
Title: Re: Uneven pad wear
Post by: Doctor Gollum on 04 June 2013, 19:31:10
:P Not another one that 'brakes' on the gearbox! It's great for the poor soul behind!  :-X  :-X

Nope, just don't brake at all.  Don't change gear much either.  Roundabouts can easily be taken at 45 in 5th  if you plan ahead. Traffic lights change if you anticipate. Pedstrians get out of the way if you don't show weakness ;)

break me, we have a Jedi in our midst. We... Well, I , am truly honoured.  ;D
Title: Re: Uneven pad wear
Post by: Andy B on 04 June 2013, 19:38:32
:P Not another one that 'brakes' on the gearbox! It's great for the poor soul behind!  :-X  :-X

Nope, just don't brake at all.  Don't change gear much either.  Roundabouts can easily be taken at 45 in 5th  if you plan ahead. Traffic lights change if you anticipate. Pedstrians get out of the way if you don't show weakness ;)

break me, we have a Jedi in our midst. We... Well, I , am truly honoured.  ;D

  ;D ;D ;D ;D ;D ;D ;D (http://www.youtube.com/watch?v=o2we_B6hDrY)
Title: Re: Uneven pad wear
Post by: dbdb on 04 June 2013, 20:13:21
the OOF empire strikes back, where is the dbug death star  though?  ;D
Title: Re: Uneven pad wear
Post by: slowboy on 04 June 2013, 20:31:58
Always descale inner & outer edges of discs when replacing pads (1st ia) :-[ :-[ :-[
Title: Re: Uneven pad wear
Post by: SMD on 04 June 2013, 22:02:27
Mine were exactly the same as in the pics, on a PFL car. Brakes were spongy with no feel
Title: Re: Uneven pad wear
Post by: Webby the Bear on 04 June 2013, 22:33:34
As you know I'm still learning my trade  :) but.......

I'd be checking that your slides move freely first of all and re-lubricate them... don't use grease as that will dry out over time. Use silicone paste.

Then I'd be checking the caliper piston moves back with ease. if it fights you going back in perhaps the inner seals gone and may need replacing.

Thirdly do you lube the pads where they move on the carrier? i'd get the crud out of there and apply new copper grease.

:)
Title: Re: Uneven pad wear
Post by: flyer 0712 on 04 June 2013, 22:42:15
Just replaced mine because of the same ...good as gold now  :y
Title: Re: Uneven pad wear
Post by: dbug on 04 June 2013, 22:57:37
the OOF empire strikes back, where is the dbug death star  though?  ;D

Laughing at you  ;D ;D ;D ;D ;D ;D