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Author Topic: Brake imbalance  (Read 1644 times)

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Greenbay packer

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Brake imbalance
« on: 24 June 2018, 12:17:15 »

Around this time last year I replaced the front brake discs and pads on my 1996 V6. Not long after that I failed an MOT with a front brake imbalance being one of the reasons for the failure - I wasn't surprised as I could feel a slight pull to the right when braking. The MOT tester said it looked like left side was working slightly slower than the right, which would explain the pull to the right if that side was braking first, and said it might be a caliper or brake hose issue. I wasn't aware of any imbalance before changing the discs and pads but can't guarantee there wasn't an issue developing. 

When I got home I checked everything, but couldn't find anything obviously wrong, so decided to work the caliper piston in and out a few times to see if that freed it if it was sticking a bit. I did that by putting in the worn pads back in so the piston would come out much further then pushing the piston back in with the bleed nipple open. At the same time I had a look under the boot over the piston and it was remarkably clean with no pitting or leaks from the seal. I also thought that rebleeding might help in case I'd missed an air bubble last time. I took the car back for a retest and it passed, but only just. I could still feel a slight pull but got the impression I might have achieved something with what I was doing.

I didn't do any more at the time as the imbalance only felt very slight and I hoped the system might bed in with use. Its now coming up to MOT time again and as I can still feel a slight use pull to the right I've had another look at the N/S front brake to see if any issue there has become more obvious. The disc still looks very good, the pads show even wear, the caliper piston still looks to be in very good clean condition and the sliders are still move freely.

As the imbalance showed up on the testers rolling road last year I'm discounting any suspension or tracking issue that might cause pulling to one side under breaking and I'm not convinced the brake hose is at fault as I would expect flow issues inside the hose to cause binding or slow brake release which is not happening. Everything keeps leading me back to the caliper being at fault and I'm wondering whether there is greater resistance on this side even though it appears to move out and push back in ok.

Many thanks if you've read through all this, I'd be grateful to hear whether others would agree that its most probably the caliper or whether there is something I've completely overlooked. I've thought about trying another caliper from a scrapper but its hard to guarantee it won't have been on the shelf for years and possibly seized and corroded.

Finally, does anyone know where I can get some bleed screws for the Lucas caliper - I'm not sure if they're a standard metric screw or if they are specific to that unit. Thank you.
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dave the builder

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Re: Brake imbalance
« Reply #1 on: 24 June 2018, 13:18:25 »

Do the pads move freely in the slides ,
had to file paint off brake pads before because they have been too tight  :-\

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terry paget

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Re: Brake imbalance
« Reply #2 on: 24 June 2018, 14:08:39 »

Are the pads all from the same set? Do the caliper sliders move freely? As it's a one piston caliper it depends upon the caliper moving freely in its guides. I had one rust solid.
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Re: Brake imbalance
« Reply #3 on: 24 June 2018, 14:45:28 »

Although the flexible brake hoses LOOK alright, its "possible" that, under pressure, one is "expanding" more than the other, so instead of moving the pads the hose expands first then moves the pad slightly later.

Might be worth checking the age of the flexible hoses and consider changing them ?? I doubt the slight expansion would be visible, its "possible" you might feel it if you hold the flexible pipe while someone brakes hard for you.

Remember, there is no "flow" in the brake lines at all, pressure applied at one end of the fluid is felt at the other as the fluid is incompressable, as the pipe expands the resultant pressure at the caliper is reduced, until the pipe stops expanding.
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Re: Brake imbalance
« Reply #4 on: 24 June 2018, 17:30:56 »

Also when was the brake fluid last changed?
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Greenbay packer

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Re: Brake imbalance
« Reply #5 on: 24 June 2018, 18:47:23 »

Do the pads move freely in the slides ,
had to file paint off brake pads before because they have been too tight  :-\

Pads move perfectly freely hence the even wear. I know what you mean about the paint though.
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Greenbay packer

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Re: Brake imbalance
« Reply #6 on: 24 June 2018, 18:49:43 »

Are the pads all from the same set? Do the caliper sliders move freely? As it's a one piston caliper it depends upon the caliper moving freely in its guides. I had one rust solid.

Pads are all from the same set, genuine GM, and the sliders are perfectly free. No sign of any corrosion on the piston as noted above.
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Greenbay packer

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Re: Brake imbalance
« Reply #7 on: 24 June 2018, 18:52:35 »

Also when was the brake fluid last changed?

12 months ago all round and yesterday for the NSF. 
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Greenbay packer

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Re: Brake imbalance
« Reply #8 on: 24 June 2018, 19:00:23 »

Although the flexible brake hoses LOOK alright, its "possible" that, under pressure, one is "expanding" more than the other, so instead of moving the pads the hose expands first then moves the pad slightly later.

Might be worth checking the age of the flexible hoses and consider changing them ?? I doubt the slight expansion would be visible, its "possible" you might feel it if you hold the flexible pipe while someone brakes hard for you.

Remember, there is no "flow" in the brake lines at all, pressure applied at one end of the fluid is felt at the other as the fluid is incompressable, as the pipe expands the resultant pressure at the caliper is reduced, until the pipe stops expanding.

Ok, maybe, I don't now how old the hoses are to be honest (5+ years since I've had the car)
but they look good and feel solid. I've not really considered expansion being an issue just thought about a constriction internally which often causes binding and slow release. Many, many years ago I had a hose on a Land Rover that went soft and squidgy and was probably expanding like you suggest but this one feels very firm and solid so I've thought it  was ok.
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terry paget

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Re: Brake imbalance
« Reply #9 on: 24 June 2018, 20:54:35 »

It could be the wishbone front bushes. I had a car, just passed its MOT, but before I handed it over to my son I wanted to correct a brake pull to the left. I had the wife drive it slowly over the inspection pit, with me in it, and brake. It then became obvious to me that the wishbone front bushes were unmatched, causing a steering twitch. I changed the wishbones, and the fault disappeared.
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Re: Brake imbalance
« Reply #10 on: 24 June 2018, 22:43:32 »

It's horrifying to watch an Omega brake hard from about 30 mph with ropey bushes... You wouldn't believe just how far the wheels move position if you haven't seen it :o
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Re: Brake imbalance
« Reply #11 on: 25 June 2018, 08:46:32 »

It's horrifying to watch an Omega brake hard from about 30 mph with ropey bushes... You wouldn't believe just how far the wheels move position if you haven't seen it :o

I know what you mean as I had an Astra pull to the right some years ago and that was due to the bushes failing but would that show as a break imbalance on a MOT tester's rolling road? The test seemed to show that one brake was operating ahead of the other one. I will have another look at the bushes though.
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Greenbay packer

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Re: Brake imbalance
« Reply #12 on: 25 June 2018, 08:52:18 »

It could be the wishbone front bushes. I had a car, just passed its MOT, but before I handed it over to my son I wanted to correct a brake pull to the left. I had the wife drive it slowly over the inspection pit, with me in it, and brake. It then became obvious to me that the wishbone front bushes were unmatched, causing a steering twitch. I changed the wishbones, and the fault disappeared.

I'll have another look at the wishbones but was assuming this kind imbalance wouldn't show like it did on the MOT brake test, i.e., indicating that one brake was operating ahead of the other?
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Kevin Wood

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Re: Brake imbalance
« Reply #13 on: 25 June 2018, 09:18:40 »

Yep, if the MOT brake tester shows an imbalance then it's clearly not down to the bushes. That doesn't mean they are OK, of course. ;)

I can't remember how the brake circuits are split on an Omega. A problem anywhere other than the caliper would affect both sides equally if they're on the same circuit, which I think they are. :-\
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Greenbay packer

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Re: Brake imbalance
« Reply #14 on: 25 June 2018, 10:38:11 »

Yep, if the MOT brake tester shows an imbalance then it's clearly not down to the bushes. That doesn't mean they are OK, of course. ;)

I can't remember how the brake circuits are split on an Omega. A problem anywhere other than the caliper would affect both sides equally if they're on the same circuit, which I think they are. :-\

Thanks for that.  Its beginning to seem like I might as well start by looking at the caliper and either replace or overhaul it.
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Re: Brake imbalance
« Reply #15 on: 25 June 2018, 10:48:06 »

Would it be possible to reconnect the brake lines in the wrong ports on the ABS block?

What effect would that have?
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Nick W

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Re: Brake imbalance
« Reply #16 on: 25 June 2018, 10:55:43 »

Would it be possible to reconnect the brake lines in the wrong ports on the ABS block?

What effect would that have?


It's hard enough connecting them correctly.
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Re: Brake imbalance
« Reply #17 on: 25 June 2018, 19:09:06 »

Yep, if the MOT brake tester shows an imbalance then it's clearly not down to the bushes. That doesn't mean they are OK, of course. ;)

I can't remember how the brake circuits are split on an Omega. A problem anywhere other than the caliper would affect both sides equally if they're on the same circuit, which I think they are. :-\

Thanks for that.  Its beginning to seem like I might as well start by looking at the caliper and either replace or overhaul it.

Just make 100% sure that the piston retracts into the caliper as easily as the other caliper.and also peel back the piston dust cover if you can to make sure itís dry inside, a small leak here can cause a small amount of air to be drawn back into the caliper as well.it could be hoses as you have previously thought but itís rare and the tester would have felt them under pressure anyway.
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Greenbay packer

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Re: Brake imbalance
« Reply #18 on: 25 June 2018, 23:00:49 »

Just make 100% sure that the piston retracts into the caliper as easily as the other caliper.and also peel back the piston dust cover if you can to make sure itís dry inside, a small leak here can cause a small amount of air to be drawn back into the caliper as well.it could be hoses as you have previously thought but itís rare and the tester would have felt them under pressure anyway.
[/quote]

Thanks, its definitely bone dry inside the boot but I think I'll do as you suggest and have a look at the other caliper too just to see if one side is moving more freely than the other. I'm guessing/ hoping the callipers are fairly easy to rebuild if the correct seal kit and/ or new piston is available.
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cam.in.head

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Re: Brake imbalance
« Reply #19 on: 25 June 2018, 23:35:14 »

Yes ,dead easy,especially as itís only a single piston type.to be honest though if the inside of the boot is dry and the piston not rusty and you can push it back nice and easy you wonít achieve much by rebuilding it the usual cause of imbalance on these is the two slider pins/bolts but you have already checked them. The way to get balanced readings(within tolerances) is to have equal physical properties each side.this means identical pad composition,disc condition,caliper condition,hose condition and all new fluid.you will never get a balance of absolute zero but one side coming on before the other USUALLY means that the faulty side has an issue somewhere.nothing to do with anything on the suspension ,bushes,tyres ,etc as the brake rollers are only measuring the effect of what it sees the brakes doing.
Have you got a good pedal!. If not you could still have an air bubble somewhere on that side in either the pipes,abs unit or caliper .
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Re: Brake imbalance
« Reply #20 on: 26 June 2018, 08:35:58 »

Yes ,dead easy,especially as itís only a single piston type.to be honest though if the inside of the boot is dry and the piston not rusty and you can push it back nice and easy you wonít achieve much by rebuilding it the usual cause of imbalance on these is the two slider pins/bolts but you have already checked them. The way to get balanced readings(within tolerances) is to have equal physical properties each side.this means identical pad composition,disc condition,caliper condition,hose condition and all new fluid.you will never get a balance of absolute zero but one side coming on before the other USUALLY means that the faulty side has an issue somewhere.nothing to do with anything on the suspension ,bushes,tyres ,etc as the brake rollers are only measuring the effect of what it sees the brakes doing.
Have you got a good pedal!. If not you could still have an air bubble somewhere on that side in either the pipes,abs unit or caliper .

Thanks for the reply, its confirmed what I was thinking particularly with being able to rule out things like suspension, tyres, etc, which is a big help. The pedal is good and firm and its position doesn't change when I pump it. I was hoping there may still have been some air somewhere and that the rebleed I've just done would help but it doesn't seem to have made any difference. I might try pumping the piston out a bit further as I've only seen about 1/2" of it so it may be in worse condition further inside the caliper. The problem only seemed to arise after I'd changed the discs and pads and the caliper piston was pushed right in to take the new pads. I've actually been contemplating putting the worn pads back in briefly just to see if there is any difference with the piston operating further out of the caliper bore but I know that's a poor idea as the old pads will be worn differently.
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BazaJT

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Re: Brake imbalance
« Reply #21 on: 26 June 2018, 19:03:44 »

If you're going to pump the piston out a bit further you'll need to put the old pads in first anyway.Whatever you do don't try pumping the piston out with nothing in the way to stop it coming out altogether.
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Re: Brake imbalance
« Reply #22 on: 01 July 2018, 11:36:32 »

If you're going to pump the piston out a bit further you'll need to put the old pads in first anyway.Whatever you do don't try pumping the piston out with nothing in the way to stop it coming out altogether.

 :y
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terry paget

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Re: Brake imbalance
« Reply #23 on: 01 July 2018, 14:07:43 »

I have driven cars with rod brakes, and cable brakes; they were all right, both had some method of compensation to achieve left right balance; it worked, often with a slight delay, causing a steering twitch as it settled down. The way you describe your fault, it sounds similar; an initial twitch one way, settling down with both sides braking evenly.
If that is the case, I don't think you should exclude suspension behaviour from possible causes. If both front wheels showed the same retardation rate after a small delay, my money is still on wishbone front bushes. With the car on a rolling road testing rig, the car does not move, but if left and right suspensions respond differently as the brakes are applied, this will appear on the testing system as a delay.
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Re: Brake imbalance
« Reply #24 on: 01 July 2018, 16:17:02 »

Hi terry if you were testing "on the road " i would agree with you 100%. Omega front suspensions are very sensitive to bushes wear and if any one was worn then they do have that strange feeling of brake pull one way and steering wheel twitch the other but i assume these brakes here were tested on rollers and one brake operates before the other does.this can surely mean that the slower side to operate has either a small air bubble still in it somewhere or a small leak in a piston seal drawing air in when pedal released.or a stiffer piston on this side,(he has confirmed that hes got matching discs,pads and checked slider pins).
My money is on a stiffer piston or air bubble.
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terry paget

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Re: Brake imbalance
« Reply #25 on: 01 July 2018, 17:28:58 »

Hi terry if you were testing "on the road " i would agree with you 100%. Omega front suspensions are very sensitive to bushes wear and if any one was worn then they do have that strange feeling of brake pull one way and steering wheel twitch the other but i assume these brakes here were tested on rollers and one brake operates before the other does.this can surely mean that the slower side to operate has either a small air bubble still in it somewhere or a small leak in a piston seal drawing air in when pedal released.or a stiffer piston on this side,(he has confirmed that hes got matching discs,pads and checked slider pins).
My money is on a stiffer piston or air bubble.
The whole point of hydraulic brakes is that all brakes get the same pressure simultaneously. That holds even when there is a bulgy hose or air in a cylinder. The rolling road brake tester presumably measures the resistance by the braked wheel to roller rotation. Roller speed is very slow, so if initially a braked front wheel can move backwards that will appear on the tester as a braking delay.
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dave the builder

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Re: Brake imbalance
« Reply #26 on: 01 July 2018, 18:47:23 »

when on the RBT
if the caliper was sticking ,the drag/bind would register
 you run up to centralize the wheels, you select which wheel to spin up
then once the roller is up to speed, the brake should be depressed gradually ,increasing to full braking or lock
then reduced gradually

Better still ,watch the MOT Matters video on brake testing
https://www.youtube.com/watch?v=xVpgCKz8oWs
but the VTS device works out the in-balance now IIRC  :-\

I know some mot testers get it wrong

also well worth watching the MOT mistakes
(which some MOT testers should watch too ,from past experience ) ;D
https://www.youtube.com/watch?v=MT8ZbRvemhg
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terry paget

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Re: Brake imbalance
« Reply #27 on: 01 July 2018, 20:52:56 »

Thanks Dave. I enjoyed those testers' guides enormously, and learned a lot from them.
The OP had a steering pull last year's MOT, tester failed the car. After some fiddling OP improved matters slightly and car just passed on retest. Car still has a steering pull and is soon due for test again. Car is 22 years old, and must have had wishbones changed. Do you know when they were last changed, Greenbay Packer? Was a new pair fitted, or just one? What make were they? As I said in post 9 of this thread, it was very obvious to me mine were faulty, watching from below as car above me braked. Without a pit its hard to imagine a simple test. Perhaps you could lever both front bushes in turn with front of the car on axle stands.
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dave the builder

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Re: Brake imbalance
« Reply #28 on: 01 July 2018, 22:09:11 »

had a caliper with a problematic piston before , very odd
kept sticking , worked it in and out and all was fine for a week or so , then the same again
I'd inspected it ,no rust etc
I replaced it with a known good used item
examined the dud unit with digital micrometer
the piston had gone "out of round"
which if you think about it ,can happen because the piston does get dragged in one direction by it's pad and calipers all the time during braking, not much but enough to cause the issue

If it was my car (or one i look after) I would buy a used replacement caliper(would be cheap and easy to get hold of) i
present for mot early , if there is an in-balance issue  then you have the spare ready to go on
but you can't rule out other issues like a dud ,semi jammed/part blocked  solenoid in the ABS module etc
IF all the slides / pads/ discs  / fluid /wheel bearing  etc is ok (including manufacturing faults so compare o/s and n/s for any slight size differences etc)
and you've checked the suspension components both sides
(it could be a duff component on on the non pulling side that makes the car pull to the problem side )

also, familiarize yourself with the RBT procedure as per the video and watch them do the test if possible  ;D

not that i'm saying your garage is one of the bad ones , it does sound like you have an issue

I just don't trust garages

I'm fortunate to have an MOT tester that is strict but fair

I've missed things in the past ,he has too , we are all human
 (though Mrs Builder may argue that point about me  :P)





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dave the builder

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Re: Brake imbalance
« Reply #29 on: 02 July 2018, 00:49:38 »

having re-read the first bit of thread and thinking  ::)
maybe the n/s lazy caliper is fine and the other side driver's ? is sticking and bites sooner
so worth getting both as free as possible  :-\


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Re: Brake imbalance
« Reply #30 on: 02 July 2018, 08:17:40 »

when on the RBT
if the caliper was sticking ,the drag/bind would register
 you run up to centralize the wheels, you select which wheel to spin up
then once the roller is up to speed, the brake should be depressed gradually ,increasing to full braking or lock
then reduced gradually

Better still ,watch the MOT Matters video on brake testing
https://www.youtube.com/watch?v=xVpgCKz8oWs
but the VTS device works out the in-balance now IIRC  :-\

I know some mot testers get it wrong

also well worth watching the MOT mistakes
(which some MOT testers should watch too ,from past experience ) ;D
https://www.youtube.com/watch?v=MT8ZbRvemhg
It was heartening to read that MOT testers should 'pass and advise' for many minor infringements, like one rear mirror missing, only 2 washer jets clear, etc.
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dave the builder

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Re: Brake imbalance
« Reply #31 on: 02 July 2018, 10:44:43 »


 It was heartening to read that MOT testers should 'pass and advise' for many minor infringements, like one rear mirror missing, only 2 washer jets clear, etc.

Or , Dis heartening to think how many MOT fails in the past should have been pass and advise or minor fault under the new system .

yep , my glass is half empty  ;D
« Last Edit: 02 July 2018, 10:51:47 by dave the builder »
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Re: Brake imbalance
« Reply #32 on: 02 July 2018, 17:54:08 »

When I recently took mine for test the front brakes were 12% out of balance.(within limits ) but I wasnít happy with that. I rechecked all the pads ,replaced the front discs and re bled the system.took it back and they were still the same.rellaced front hoses ,re bled and tried again. Still the same.garage said they were fine and nothing I could do would make them 100% perfect. No cars are apparently.no signs of any pull either.
I still wanted them better so I rebuilt both calipers noticing that the lower side DID have some slight rusting on the piston ( the others were finger push,this was tighter but not in any way seized)and a SLIGHT wetness on piston.
Rebuilt,all finger push to retract now,rebled and back again.
Brakes now less than 1% out of balance.(0.7%) 229/230
So mine was definately a caliper issue. To be honest I donít think it was the slightly stiff piston,more like the slight leak drawing a very small amount of air in on release.
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Re: Brake imbalance
« Reply #33 on: 02 July 2018, 20:53:10 »

When I recently took mine for test the front brakes were 12% out of balance.(within limits ) but I wasnít happy with that. I rechecked all the pads ,replaced the front discs and re bled the system.took it back and they were still the same.rellaced front hoses ,re bled and tried again. Still the same.garage said they were fine and nothing I could do would make them 100% perfect. No cars are apparently.no signs of any pull either.
I still wanted them better so I rebuilt both calipers noticing that the lower side DID have some slight rusting on the piston ( the others were finger push,this was tighter but not in any way seized)and a SLIGHT wetness on piston.
Rebuilt,all finger push to retract now,rebled and back again.
Brakes now less than 1% out of balance.(0.7%) 229/230
So mine was definately a caliper issue. To be honest I donít think it was the slightly stiff piston,more like the slight leak drawing a very small amount of air in on release.
Were there any other symptons, apart from the MOT brake test imbalance? Like a steering twitch on initial braking? After the initial imbalance, did both brakes show the same braking force?
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cam.in.head

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Re: Brake imbalance
« Reply #34 on: 02 July 2018, 23:34:08 »

Looking at his first post he did state that it pulled to the right as the left brake wasnít as good.then by thorough checking he got it to just pass mot.so it does sound like an issue with that left caliper one way or another.i beleive thatís what he is now concentrating on.no doubt we will soon find out.as we know they are prone to the slider pins seizing but heís done that.
My imbalance which wasnít enough to call an imbalance apparrently was just something that I personally wanted to get to as near. 100% as I could.its on my early cav with twin piston calipers and the slight stiffness (and it was slight) or the slight leak( which Iím convinced was the actual issue)was enough once overhauled brough them back to virtually 100%.
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Re: Brake imbalance
« Reply #35 on: 08 July 2018, 18:43:17 »

Thanks Dave. I enjoyed those testers' guides enormously, and learned a lot from them.
The OP had a steering pull last year's MOT, tester failed the car. After some fiddling OP improved matters slightly and car just passed on retest. Car still has a steering pull and is soon due for test again. Car is 22 years old, and must have had wishbones changed. Do you know when they were last changed, Greenbay Packer? Was a new pair fitted, or just one? What make were they? As I said in post 9 of this thread, it was very obvious to me mine were faulty, watching from below as car above me braked. Without a pit its hard to imagine a simple test. Perhaps you could lever both front bushes in turn with front of the car on axle stands.

Thanks for the replies and sorry for the slow response - just back from holiday. I'm going to check the wishbones again as much as anything to make sure I don't have two faults at the same time - its always possible I've sorted the caliper issue, hence the improvement which got the car through the last MOT, but also have a wishbone bush starting to fail which is responsible for the slight twitch and straighten I can feel now. Not entirely sure how old the wishbones are off hand but both sides have been changed more than once. Current wishbones are Delphi, which certainly looked ok.
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Re: Brake imbalance
« Reply #36 on: 08 July 2018, 18:51:55 »

When I recently took mine for test the front brakes were 12% out of balance.(within limits ) but I wasnít happy with that. I rechecked all the pads ,replaced the front discs and re bled the system.took it back and they were still the same.rellaced front hoses ,re bled and tried again. Still the same.garage said they were fine and nothing I could do would make them 100% perfect. No cars are apparently.no signs of any pull either.
I still wanted them better so I rebuilt both calipers noticing that the lower side DID have some slight rusting on the piston ( the others were finger push,this was tighter but not in any way seized)and a SLIGHT wetness on piston.
Rebuilt,all finger push to retract now,rebled and back again.
Brakes now less than 1% out of balance.(0.7%) 229/230
So mine was definately a caliper issue. To be honest I donít think it was the slightly stiff piston,more like the slight leak drawing a very small amount of air in on release.

I'm going to have a look at both callipers again, this week I hope. Although both are going in and out ok I may be able to feel if one is a bit freer than the other when I push the piston back in.
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Re: Brake imbalance
« Reply #37 on: 08 July 2018, 18:56:36 »

I wouldn't fit Delphi wishbones to a scrapped Omega for banger racing ::)

Last one I fitted lasted less than a week. Start there :y
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Re: Brake imbalance
« Reply #38 on: 08 July 2018, 19:01:28 »

had a caliper with a problematic piston before , very odd
kept sticking , worked it in and out and all was fine for a week or so , then the same again
I'd inspected it ,no rust etc
I replaced it with a known good used item
examined the dud unit with digital micrometer
the piston had gone "out of round"
which if you think about it ,can happen because the piston does get dragged in one direction by it's pad and calipers all the time during braking, not much but enough to cause the issue

If it was my car (or one i look after) I would buy a used replacement caliper(would be cheap and easy to get hold of) i
present for mot early , if there is an in-balance issue  then you have the spare ready to go on
but you can't rule out other issues like a dud ,semi jammed/part blocked  solenoid in the ABS module etc
IF all the slides / pads/ discs  / fluid /wheel bearing  etc is ok (including manufacturing faults so compare o/s and n/s for any slight size differences etc)
and you've checked the suspension components both sides
(it could be a duff component on on the non pulling side that makes the car pull to the problem side )

also, familiarize yourself with the RBT procedure as per the video and watch them do the test if possible  ;D

not that i'm saying your garage is one of the bad ones , it does sound like you have an issue

I just don't trust garages

I'm fortunate to have an MOT tester that is strict but fair

I've missed things in the past ,he has too , we are all human
 (though Mrs Builder may argue that point about me  :P)

That is interesting. If the piston has gone slightly 'out of round' like you say it could explain why the fault seemed to appear when I changed the pads and the piston - i.e., the piston may have round in the old position for the worn pads. Also I'm going to do as you suggest and try and find another caliper to play around with - if I'm lucky I might be able to find one that has been in use recently and is still ok. I'm also going to have another look at my wishbones.
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Re: Brake imbalance
« Reply #39 on: 08 July 2018, 19:02:51 »

I wouldn't fit Delphi wishbones to a scrapped Omega for banger racing ::)

Last one I fitted lasted less than a week. Start there :y

No idea they were that bad, will check them again.
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Re: Brake imbalance
« Reply #40 on: 08 July 2018, 19:03:47 »

I wouldn't fit Delphi wishbones to a scrapped Omega for banger racing ::)

Last one I fitted lasted less than a week. Start there :y

I had the same experience with my beloved TD Estate years ago. Fitted Delphi, they lasted less than a year. >:(
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Greenbay packer

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Re: Brake imbalance
« Reply #41 on: 09 July 2018, 10:32:30 »

I wouldn't fit Delphi wishbones to a scrapped Omega for banger racing ::)

Last one I fitted lasted less than a week. Start there :y

I had the same experience with my beloved TD Estate years ago. Fitted Delphi, they lasted less than a year. >:(

Thanks for the reply.  The only reason I fitted them was that I've had a set of Delphi's on our workhorse Astra and they've been great for many years so I thought they'd be ok on the Omega too. Previous (unknown brand) set fitted to the Omega by a local garage lasted barely 18 months with very low mileage so I was hoping to improve on that.  Is there a brand that is recommended other that GM?
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Re: Brake imbalance
« Reply #42 on: 09 July 2018, 10:59:21 »

The ATP set for £69 is about the best value available  ;)

Currently on ebay.
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Re: Brake imbalance
« Reply #43 on: 10 July 2018, 18:49:05 »

The ATP set for £69 is about the best value available  ;)

Currently on ebay.

Had a look just in case I need them but couldn't find on eBay.
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Shackeng

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Re: Brake imbalance
« Reply #44 on: 10 July 2018, 19:07:33 »

The ATP set for £69 is about the best value available  ;)

Currently on ebay.

Should that be All German AL?
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dave the builder

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Re: Brake imbalance
« Reply #46 on: 10 July 2018, 21:59:32 »

The ATP set for £69 is about the best value available  ;)

Currently on ebay.

Should that be All German AL?
Not as long as I have a hole in my arse ;)

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Re: Brake imbalance
« Reply #47 on: 10 July 2018, 22:00:13 »

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Re: Brake imbalance
« Reply #48 on: 12 July 2018, 09:57:56 »

Thanks.
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Re: Brake imbalance
« Reply #49 on: 12 July 2018, 17:58:16 »

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