Your brake drums need a good clean out.
>>
Don't breathe in the dust when doing this! Dust of all kinds is harmful and the fibres used to replace asbestos are terrifyingly similar in many respects. Wear a dust mask.
|
|
Sorry, I forgot to mention this. I assumed the garage who couldn't find anything wrong would be doing the cleaning. Even the fast tyre chains should be able to manage a de-dust but then you risk being told you need a new set of brake shoes, 4 new tyres, tracking, dampers and a new exhaust!
|
Rear brakes sticking has been a long standing issue on Vauxhalls with rear drum brakes. Since the early 1980's in my experience!
Usually, as mentioned above, a good strip, clean, *lubricate* and adjust of the rear brakes is probably all that is needed. While the drums are off, you should also check both the wheel cylinder and handbrake cable for smooth operation.
If there are cylindrical rivet depressions in the linings, take particular care to ensure these are fully cleaned out. (Some rivets used to be hollow - not sure now) Any dust left in these rivet holes can form sticky goo, which 'sucks' onto the drum.
number_cruncher
|
>>Rear brakes sticking has been a long standing issue on Vauxhalls with rear drum brakes. Since the early 1980's in my experience!
Its Been a problem with Vauxhalls since the HA viva/Victors.
Main problem is. These days its rare the drums are even removed
all they do now is use inspection hole in the backplate. if the shoes look ok and all work fine. Then the drum isnt removed.. missing the fact dust has built up..Have seen it all too often.
By rights they should be removed on full service though it doesnt very often happen. Had FIL`s corsa drums off last weekend.. full of dust didnt look like drums had ever been off
--
Steve
|
As well as the advice already given, chamfer the front and rear edges of the shoes with a file.
The rear brakes of an old Astramax Van I had access to used to stick after being left parked up overnight, it went into the Vauxhall garage 3 times before finally being sorted out. Once one of the more experienced mechanics finally got his hands on it, all he did was to put a chamfer on the leading and trailing edges of the rear brake shoes. Never a problem afterwards.
|
Good point DD. For any Vauxhall owners that have drum Brakes. It was always a point to Chamfer front and rear edges of the shoe.. general idea is. That the dust rolls over the shoe causing either a squeel or as here suction while wet.Locking the shoe to drum..The chamfer prevents roll over. The dust sticks to or gets caught on chamfer edge..The car still needs the drums Removed and cleaned at full service interval though
--
Steve
|
The cheapskate option:
don't use the handbrake.
You have a perfectly good gearbox, so if leaving the car parked up overnight, make sure it is on a level surface & put it in gear.
Easy. Free. And I'm serious.
::puts on tin hat for shower of bullets!::
|
>>don't use the handbrake.
One reason why rear brakes dont self adjust..Handbrake rarely used?
--
Steve
|
>>don't use the handbrake. One reason why rear brakes dont self adjust..Handbrake rarely used? -- Steve
This can't be the case, because the self adjusters work when the footbrake is used on this type (and most types?) of self adjusting drum brakes.
Use, or lack of use of the handbrake has nothing to do with the self adjusters in this case.
number_cruncher
|
NC to be honest.I have never known them to work anyway. Has always been a case of adjust rear brakes on main service..Some times before..You may be lucky enough to have come across the odd few that do work. Fraid I havent and do make a point of checking.
--
Steve
|
Steve,
Yes, these aren't the most effective devices known! They can't be cheap to make either. I can't say I've seen more than the odd few that do work, and I too have been looking.
While the ratchet teeth are still in good nick, I am a fan of the Ford self adjuster - very simple and effective.
number_cruncher
|
|
I have chamfered the leading and trailing edges to 'cure' one or two 'problem cases'.
The problem I have is that I don't understand why it works.
In the case of a grabbing brake, I understand how it may reduce self servo as the drum rotates, but for a sticking brake, and a stationary drum, I just don't get it!
number_cruncher
|
|
As has been said, this has always been a Vauxhall problem. Usually a sharp clout on the (steel only) wheel with a decent hammer will release them - this shouldn't have to be done these days though. Maybe it's something to do with the brake drum material. With most drums you can tap with a hammer to remove it without any damage. With a Vauxhall this ALWAYS results in chips of brake drum flying off. A softer, stickier sort of cast iron maybe ?
|
Garage are supposed to have stripped them down & given a good clean. They were OK for one day, but stuck again the next. As car has alloys I cannot use the hammer technique so not sure what to do when they stick again. Unfortunately, drive is not level so cannot leave handbrake off.
Will try and have a look myself at the weekend to see if I can see anything untoward.
Know what you mean about it being a Vauxhall problem though - happened to all four of ours over the years. Best was our E reg Astra - Vauxhall told us we required new rear brakes, which they fitted. Kept sticking, kept taking car back, kept saying nothing was wrong. Two weeks later, MOT, same Vauxhall garage failed it on guess what? the rear brakes. Excuse was they no longer put asbestos in brake parts, so the sealed unit build up with moisture (so how does it get in if they are sealed???).
|
Rear drums are not sealed..If you go through a flood. water enters the brake drum. I wonder if you may be better off taking car elsewhere to have work done
--
Steve
|
|
Yep, rear brakes definitely aren't sealed.I haven't had any problems with the brakes binding, however, it is apparently easy to set the self adjustment system up backwards so they no longer adjust. (just pulls them further apart)
|
I wonder if you may be better off taking car elsewhere to have work done
Seriously considering it now - only reason why I took it back there is because its still under warranty, only got it a month ago and had problems with both them and it since day one
|
|
If it's any consolation, just had the garage look at my Renault Megane for the same problem - like yours, they cleaned out the drum but I notive they are doing the same thing today. Guess leaving it in gear is a good option!
|
Depends on what they call cleaning. ie was it just a quick spray with brake cleaner to wash the dust away..correct way to do it. Is using emery cloth or something similar "not sandpaper" rub surface off shoes. The glazed surface.. Then rub down brake drum interior around contact area of the shoe..This then breaks the glaze making a slighty rough surface..This prevents water ingress from locking the shoe to drum
This method was always used by Vauxhalls to prevent lock up.At least back in the 70`s
I have never had a problem with them.Or any other car
--
Steve
|
Steve - I was just going to mention the deglazing; this will cure it.
--
groups.msn.com/honestjohn - Pictures say a thousand words.....
|
DL. wonder why garages dont even try to correct. As you know its not a long job..
--
Steve
|
Yeah - exactly Steve - it would take an extra 10 minutes to chamfer the shoes off and deglaze the friction surfaces.....but techs these days probably haven't been shown how to do it!
.....Plus it would count against their bonus payments ;)
--
groups.msn.com/honestjohn - Pictures say a thousand words.....
|
DL. wonder why garages dont even try to correct. As you know its not a long job..
The "old hands" are more aware of it, but the "young 'uns" haven't a clue unless there's an interface somewhere to plug their diagnostic kit into.
|
|
|
|
|
This phenomenon (bang from rear brakes when moving off in reverse) occurs both on my Passat (rear discs) and my girlfriend's Fiesta (rear drums). It only happens when it's been raining or I've just washed the car (and therefore the wheels).
I've often wondered what it might be. So it can happen with discs too?!
|
|
Lots of good advice about toe'ing and heeling brake shoes, deglazing etc. The trouble is, most of the time it works for about 5mins - then it's back to square one. No amount of adjustment or fiddling about will alter the 'sticky' nature of a wet and rusting cast iron drum with a brake shoe pressed firmly against it for 12 hours or so. (Gigantic pull off springs maybe ?) As for disc brakes, front's don't usually stick as the pads are withdwawn slightly as the brake is released, but the first application after overnight parking with wet brakes might result in a grinding noise as the rust is wiped off. Rear pads might stick as they are clamped to the disc by the handbrake.
|
>>No amount of adjustment or fiddling about will alter the 'sticky' nature of a wet and rusting cast iron drum
Idea of deglazing is to prevent suction occuring..It isnt a five minute wonder. Have been in the trade many years. And I gather you read my post on Vauxhalls using this approach..It was in the 70`s. I gather. its not performed now..Idea is to remove any chance of suction occurring between brake shoe and drum..Never had a problem with it as I mentioned..Ps thats assuming You understand the prob?
--
Steve
|
The issue is still ongoing - last weekend, I was in the workshop of my old place of work, and, to allow it to move onto the ramp, the back plates of a newish Meriva had to be tapped 'judiciously'!
I know that deglazing, etc. works. I'm still not sure about *why* the chamfering of leading and trailing edges works. Nor am I happy about why the surfaces need to be deglazed. Surely if it were a simple surface finish problem, the drums could be made with the appropriate surface finish from day one? Why does the glazing build up?
On Vauxhalls, I do tend to go round the surfaces with emery paper at every big service, but this has not given complete immunity from sticking brakes.
number_cruncher
|
NC to explain. This is Vx explanation going back to 1972..however it was used and worked before this time.As it was worked out why..Scraping the drum inner surface allowed air into the scraped section of the drum..Scraping the shoe made the shoe rough.allowing air into the shoe surface.Water when applied wasnt able to stick to either surface due to air inbetween.I did mention why chamfering worked though from what you mentioned it I gather it hasnt worked?
--
Steve
|
Steve O
I do have a good understanding of vehicle braking systems. I'm a qualified motor mechanic with over 40yrs experience in the transport industry. I currently maintain a fleet of 90 hire vehicles ranging from Caddy vans (lots of incurable brake squeal and premature rear brake lockup with them), to Iveco / Man 7.5tonne trucks. Like yourself, in the past, I've worked on Vauxhall brakes and to be honest I've always found them to be more problematical than say a Ford. I mean, going back to the 70's they might fit a Lockheed master cyl. and Girling wheel cyls. Where they have been consistent is in the fitting of 'awkward' and cheap flimsy brake drums. I don't work on Vauxhalls these days, but it seems that the problem persists. Not that the problem of sticking brakes is just a Vauxhall problem, it just seems to affect other makes less.
What can be a problem with all cars is what's known as a 'light use glaze'. This occurs when the braking surfaces never reach the temperature they are designed to work at. The surfaces become polished and glazed. This can cause brake squeal (and maybe sticking). The answer is a bit of VERY heavy braking now and then to deglaze the surfaces.
|
I agree with what you said..Also surprised the problem still exists..I thought it had dissapeared many moons ago.But as with other problems they still do. I cannot fault what you said and totally agree..Apart from those that dont Hard brake. Still need this done..Ps my comment was a Vx point not mine apart from the fact I got the date wrong by 2 years.Still stands.
--
Steve
|
|
|
|
|
