Brake pads - checking hoses and tools needed

d215yq

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Hi All,

I really want to change my brake pads myself. When I had some inspections done for the MOT one place (not MOT) said the hoses were not in good condition. So some questions:

1) What would a corroded break hose consist of - OK I get the rubber is probably 32yrs old but I have inspected one side F+R with the wheels off, cleaned all the dirt off and cannot see anything nor feel anything other than smooth uncracked rubber for the whole hose without a perforation or crack in sight. As it doesn't leak and feels like this, is there any other signs to show it needs changing? The same garage did say the V belt was warn too and it is very very lightly cracked but not worth replacing so maybe they're just looking for work?

2) What tools do I need to do the pads. I have a full 1/2" quality socket set and screwdrivers, etc but nothing else. I take it I need a jack and axle stands (which I want to get anyway) but do I need allen keys/non standard bolt fittings/greases etc?

3) As the car brakes fine as it is and the fluid was changed 3 yrs ago and there is no catching/problems other than being told the pads are low, can I just simply do only the pads and nothing else? As it's first time on the brakes that would be ideal to just do the pads - I have a quote from a garage of 220€ to replace the F+R pads and I park 200m from them when doing this. Bosch pads are coming out at 12€ for rears and 22€ for front so that's 34€ for parts 65€ for the jack/stands so I get the jack and stands and 120€ saving.

I'll also only do the rears first and then drive it a bit so I know I've done it right before I do the fronts. Worst case if I can't complete it I can drive it 200m to the garage anyway, or even if I just to the rears then that's still halved the cost.
 

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You will need a socket set which you already have, yes, some allen keys, I think 7mm is the most common size for the brakes although having a couple of smaller and larger sizes will help as you build your toolbox, you can either buy a set (get long handled ones if you go down that route) or 1/2" sq drive mounted type to match up to your socket set.

You'll also need some copper grease, a tooth paste sized tube will last for several b/pad changes, plus, the brake fluid should be changed every two or three years depending on your model, check your owners manual, it'll tell you, there may even be a section in the service book with the necessary information.

You Tube is a mine of tutorials to help you find the right method to use. Watch a couple of different ones, that way you can pick up as many ideas and as much info as you can.

The corrosion that the garage reported may just have been the dirt that you cleaned off, although it sounds like they may have just been up selling to me. If there are no cracks or other obvious damage to the hoses they will most likely be ok. However, if you suspect that they are as old as that, I'd think seriously about getting them changed anyway. If you are a novice to this type of work I'd strongly recommend that a garage or someone with experience changes them as, the brake system will need to be bled after changing the hoses.

If you have a friend or know someone who is up to speed with the brakes ask them to help check out your work. That way you can have confidence that the brakes will stop you when the jobs done. Don't forget that the brakes will need to bed in after the job is done so they will not be as good or bite as well as they will when they're bedded in. Take care!
 
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d215yq

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You will need a socket set which you already have, yes, some allen keys, I think 7mm is the most common size for the brakes although having a couple of smaller and larger sizes will help as you build your toolbox, you can either buy a set (get long handled ones if you go down that route) or 1/2" sq drive mounted type to match up to your socket set.

You'll also need some copper grease, a tooth paste sized tube will last for several b/pad changes, plus, the brake fluid should be changed every two or three years depending on your model, check your owners manual, it'll tell you, there may even be a section in the service book with the necessary information.

You Tube is a mine of tutorials to help you find the right method to use. Watch a couple of different ones, that way you can pick up as many ideas and as much info as you can.

The corrosion that the garage reported may just have been the dirt that you cleaned off, although it sounds like they may have just been up selling to me. If there are no cracks or other obvious damage to the hoses they will most likely be ok. However, if you suspect that they are as old as that, I'd think seriously about getting them changed anyway. If you are a novice to this type of work I'd strongly recommend that a garage or someone with experience changes them as, the brake system will need to be bled after changing the hoses.

If you have a friend or know someone who is up to speed with the brakes ask them to help check out your work. That way you can have confidence that the brakes will stop you when the jobs done. Don't forget that the brakes will need to bed in after the job is done so they will not be as good or bite as well as they will when they're bedded in. Take care!

Thanks for that, very useful, I've been on youtube and watched a few videos, it looks easy but they always make it look so. I won't touch brake fluid myself, I just want to know what I'm looking for on the hoses while doing it to see if they needto be done by someone else. When I say they are 32 years old that's the age of the car - I've no idea if they've been replaced before but I'm not going to get into the "it might be 32 years old I'll just replace it" mantra or I'd also do all pipes, master cylinder, caliper, and it would never stop!

I don't have anyone to check my work but if I do rears first and then let them bed in before doing fronts that should give me a good heads up on what's involved and how it worked out. I am assuming that any problems for the job come with not being able to dismantle things rather than the reassembly - that's almost always what I find with mechanics, so worst case if I'm stuck halfway through I just reassemble and drive 200m to garage to do it...
 

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Thanks for that, very useful, I've been on youtube and watched a few videos, it looks easy but they always make it look so. I won't touch brake fluid myself, I just want to know what I'm looking for on the hoses while doing it to see if they needto be done by someone else. When I say they are 32 years old that's the age of the car - I've no idea if they've been replaced before but I'm not going to get into the "it might be 32 years old I'll just replace it" mantra or I'd also do all pipes, master cylinder, caliper, and it would never stop!

I don't have anyone to check my work but if I do rears first and then let them bed in before doing fronts that should give me a good heads up on what's involved and how it worked out. I am assuming that any problems for the job come with not being able to dismantle things rather than the reassembly - that's almost always what I find with mechanics, so worst case if I'm stuck halfway through I just reassemble and drive 200m to garage to do it...


From what you've described on your initial post the hoses sound fine, as long as there are no cracks and the pipes don't swell when you apply pressure to the brake pedal they'll most likely be fine.

I understand what you mean about the "mantra" however, their is also the old "if it ain't broke, don't fix it" one too. :p

I've looked up a photo of which car you have, so now have a better idea of what your dealing with.

I've also watched the replacing rear pads video on You Tube too.

Fortunately they are one of the easiest types of calipers in which to change the pads, as long as they haven't seized in.

It really is as simple as the videos makes it look. As a further suggestion, regarding tools required, I'd add a smaller sized wire brush to help clean up the caliper working parts as much as possible, cleanliness helps with the strip down side of things and a face mask to protect your lungs from from the brake dust, fortunately the pads are no longer made from an asbestos material with can be fatal if inhaled (although not immediately, it usually takes 20 years or so to kill you), however it's still not a good idea to inhale any brake dust, so take care.

In the videos they don't show the use of copper grease at all, which is a mistake, as it helps enormously, to prevent brake squeeks and squeals as well as lubricating the slides and pins which helps everything move as and when it should.

I suspect it is not shown to prevent accidental contamination of the pad friction material and disc face which would be disasterous. No brakes!!!

Basically just look at everything before you start to strip it, try to be methodical as you take it apart and sit it down in such a way as to help you remember how to reassemble everything in the correct order. Use the video to help you if you get stuck. Another thing I noticed on the video is that they don't show the master cylinder cap being removed prior to pressing the pistons on the caliper back in, this is a must! Just don't forget to wrap a cloth around the reservoir to collect any spillage of brake fluid particularly if the reservoir is full, if you do have spillage do not leave it on the paint work as it will remove it and cause damage. Wipe it off immediately with a clean dry cloth.

Don't forget to re-tighten the cap when you have finished the job.

I'm sure you will manage fine, good luck my friend and remember to enjoy yourself, the feeling of satisfaction when you've finished will be enormous! ;) :) :D

If you need anymore questions answered just ask and I'll do my best to help. I was going to say I'd pop round when I noticed that you're in Barcelona. According to google maps it would take me 22.5 hours to drive the 2,208.5 kilometers plus the ferry or channel tunnel to get to you, lol. :D :D :D
 
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d215yq

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Thanks again, that's the sort of encourgaement I need so I've ordered everything and now will wait until I have a free weekend and no use for the car for 4 or 5 days so I can do it without any pressure/hurry and keep referring to your posts/the videos if necessary.

I will report back on how it goes but it might be a few weeks until I try it. I'm actually in Valencia now which is even further - and don't I know it having done the Valencia-London-Valencia drive twice this year. It is rather nice through Spain/France though if not in a hurry and taking the scenic route and a good old run for any car. The engine certainly seems to run nicer after 2x 8hr days of a road/b road cruising.
 

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Thanks again, that's the sort of encourgaement I need so I've ordered everything and now will wait until I have a free weekend and no use for the car for 4 or 5 days so I can do it without any pressure/hurry and keep referring to your posts/the videos if necessary.

I will report back on how it goes but it might be a few weeks until I try it. I'm actually in Valencia now which is even further - and don't I know it having done the Valencia-London-Valencia drive twice this year. It is rather nice through Spain/France though if not in a hurry and taking the scenic route and a good old run for any car. The engine certainly seems to run nicer after 2x 8hr days of a road/b road cruising.
Do Haynes do a repair manual for your car model ?
 
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d215yq

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Do Haynes do a repair manual for your car model ?

It appears they do..that's a good shout, I remember having one of those for my first car (Rover 214) and it was pretty useful.
 

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Do Haynes do a repair manual for your car model ?

Excellent idea Wighty, I wasn't sure if there had been a manual produced for the W124 300D, however, if there has, buying/ obtaining one would be a great idea, they are full of so much useful information.
 
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d215yq

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Well I finally got round to changing the rear ones and they are indeed very easy, other than not knowing whether to take off the metal bits stuck onto the backing plate (still awaiting an answer on whether this has to be removed or not and whether I have to do one wheel again!)... it did not take long.

The fronts are going to be a bit more of a challenge with caliper removal but I feel I can do it - and the rears atleast had no issues - pins came out, calipers reset, pads came out all without much leverage/force needed ar all. The trouble is as a garage put the wheels on too tight I can't get the wheels off. The rears I've done myself and as always just stand on the brace to tighten and then they require a kick to get them off - and never had a problem. Or should I be doing them tighter? Because the garage have done them so tight it's impossible to get them off with the normal brace which to me seems wrong. So does anyone have any way with a normal brace to get the overtightened wheels off - can I hit it the brace with a hammer/use penetrating fluid or are these a no on wheel bolts? They're alloy wheels if it makes a difference and only fitted 5 months ago so shouldn't be rusted up, etc.

Another question, more for interest...the same garage that tightened my wheels also said all my pads had 5k kms braking left. Well I've done 10kkms since then (though I don't brake hardly at all) and the rears look like the attached photo - 4mm from base and 1,5mm from bottom of groove in the middle - would you say the garage are exaggerating and those have life in them yet or were these very much due for replacement? I ask because the garage also said new front brake pads and all round brake hoses and poly V belt were needed and the hoses, in the rear atleast are pretty much like new once I cleaned the dirt off them and also the poly V belt looks fine other than some slight hairline cracking which according to the internet is normal...So not sure I trust them.
 

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EmilysDad

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There's loads of life left in that pad ... the slot in the middle acts as the low warning ie when the slot has worn away, you needed new pads last week ;)
As for the tight wheel nuts, go back the garage & ask them to undo them for you and re-torque correctly .... can't think off hand what they should be
 
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d215yq

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There's loads of life left in that pad ... the slot in the middle acts as the low warning ie when the slot has worn away, you needed new pads last week ;)
As for the tight wheel nuts, go back the garage & ask them to undo them for you and re-torque correctly .... can't think off hand what they should be

OK so if it's 1.5mm to the groove that acts as the warning, how many miles is 1.5mm for someone who brakes very little? To be fair the car has done 100k miles in my ownership never replacing neither front or rear pads (and as there was no history, could have been many miles before that) so I didn't question it when they said I needed front and rear in 5kkms more...anyway it's done now, I'm just thinking I won't be in a hurry to do the fronts. Will maybe have the wheels balanced somewhere else (think they might need it) and will ask them not to tighten them much so I can do the fronts when I feel like it. I bought the pads so there's no poin in not replacing them now.
 
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d215yq

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How long is a piece of string? ;)

I know I know it's a sill yquestion, to put it another way for future use when I start looking at these things myself, at what mm of useful material do people replace their brakes. I know for tyres it's 1,6mm legal and 2.5mmish recommended. Is there a similar recommendation for pads.

I've never seen any before I ordered them so can only conlcude tha the new ones have more life than the old ones but not sure of anything else
 

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I know I know it's a sill yquestion, to put it another way for future use when I start looking at these things myself, at what mm of useful material do people replace their brakes. I know for tyres it's 1,6mm legal and 2.5mmish recommended. Is there a similar recommendation for pads.

I've never seen any before I ordered them so can only conlcude tha the new ones have more life than the old ones but not sure of anything else

A quick Google suggests there's min legal limit of 1.5mm but 3 mm is a good point to change them.
 
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d215yq

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A quick Google suggests there's min legal limit of 1.5mm but 3 mm is a good point to change them.

That makes sense as the "wear grooves" are at 2.5mm so that fits in with what you are saying i.e. change before 2.5mm. I'll remember this in future.
 

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OK so if it's 1.5mm to the groove that acts as the warning, how many miles is 1.5mm for someone who brakes very little? To be fair the car has done 100k miles in my ownership never replacing neither front or rear pads (and as there was no history, could have been many miles before that) so I didn't question it when they said I needed front and rear in 5kkms more...anyway it's done now, I'm just thinking I won't be in a hurry to do the fronts. Will maybe have the wheels balanced somewhere else (think they might need it) and will ask them not to tighten them much so I can do the fronts when I feel like it. I bought the pads so there's no poin in not replacing them now.

Everyones braking technique and style is different, for example, I know I am quite hard on my brakes, I expect to get approx, 20K miles out of a front set of pads and around 30K out of a set of rears.

However, as Emilys Dad says, "how long is a piece of string?".

It also depends on the condition of the components, (discs and pads), the make, the quality, your driving style, how hilly the area you live and drive on are. So, not an easy question to answer my friend.

As you have already changed them I would give them a check at 10K and then evaluate the wear rate from there.

The ones you have taken off I'd assess as having less than 5K (for my driving style, I might add) however, if you are as gentle on the brakes as you say, you potentially, could get considerably more out of them. I think checking regularly, every 3-5K when they get that low would be my method. You may be able to get away with checking them less, I tend to go on the better safe than sorry methodology myself. Mainly I think, because replacing pads is relatively cheap and as you have discovered quite easy. If you let them get metal to metal with the discs then you have the added expense and work of replacing the discs too.

As for the tightness of the wheel nuts, there is a specific torque setting for them, if you managed to get yourself a Haynes manual for the car as you mentioned before, I'm sure that the figure required will be in it.
On my C207 Coupé the torque setting for the wheel nuts is surprisingly high, you couldn't manage to loosen them with the little wheel wrenches that most manufacturers supply as standard. I have a 24" samson bar which I use to undo mine and they do seem tighter sometimes. I must just be getting old. :D

I would ask the garage to put the nuts on manually rather than by using the buzz gun as so many do. Just remember if you are doing the wheel nuts yourself always loosen the locking nut first on removal and tighten up last at refitting, it just needs to be tight and no more, no point in making trouble for oneself at removal time. :p
 

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have to say following.
1) garage stated corroded brake hose, i suspect they mean a corroded brake pipe (the metal pipe that connects to the rubber brake hose) check all your pipes, and if corrosion is not that bad, clean up and paint.
2) a 1 meter breaker bar would be your best friend along with your socket set to get the wheel bolts undone. They also need to be tightened to correct torque after re fitting. I breaker bar is quite a cheap item, a torque wrench a bit more money.
 

Jimbo1959

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Well I finally got round to changing the rear ones and they are indeed very easy, other than not knowing whether to take off the metal bits stuck onto the backing plate (still awaiting an answer on whether this has to be removed or not and whether I have to do one wheel again!)... it did not take long.

Were the metal bits very thin and made from a hard but semi flexible material?
If so, they are called brake pad shims. It is not entirely necessary to fit them, although they do help, as they are there to prevent premature wear on the pad plate which is usually made from a softer metal that the caliper piston and to help prevent pad squeal too. However, I wouldn't worry too much unless you are a perfectionist or perhaps have OCD. :D
 
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d215yq

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Everyones braking technique and style is different, for example, I know I am quite hard on my brakes, I expect to get approx, 20K miles out of a front set of pads and around 30K out of a set of rears.

However, as Emilys Dad says, "how long is a piece of string?".

It also depends on the condition of the components, (discs and pads), the make, the quality, your driving style, how hilly the area you live and drive on are. So, not an easy question to answer my friend.

As you have already changed them I would give them a check at 10K and then evaluate the wear rate from there.

The ones you have taken off I'd assess as having less than 5K (for my driving style, I might add) however, if you are as gentle on the brakes as you say, you potentially, could get considerably more out of them. I think checking regularly, every 3-5K when they get that low would be my method. You may be able to get away with checking them less, I tend to go on the better safe than sorry methodology myself. Mainly I think, because replacing pads is relatively cheap and as you have discovered quite easy. If you let them get metal to metal with the discs then you have the added expense and work of replacing the discs too.

As for the tightness of the wheel nuts, there is a specific torque setting for them, if you managed to get yourself a Haynes manual for the car as you mentioned before, I'm sure that the figure required will be in it.
On my C207 Coupé the torque setting for the wheel nuts is surprisingly high, you couldn't manage to loosen them with the little wheel wrenches that most manufacturers supply as standard. I have a 24" samson bar which I use to undo mine and they do seem tighter sometimes. I must just be getting old. :D

I would ask the garage to put the nuts on manually rather than by using the buzz gun as so many do. Just remember if you are doing the wheel nuts yourself always loosen the locking nut first on removal and tighten up last at refitting, it just needs to be tight and no more, no point in making trouble for oneself at removal time. :p

Well a typical journey is drive 2 miles in town so a few stops from 30mph and then maybe 200 miles on mways/long sweeping a roads where the brake isn't touched until the final 2 miles of the journey - but there are a few journeys where I go up and down mountain passes but I really can go for 100s of miles without braking on the road network round here. I'm glad the rears are done and happy to fit the fronts even if they do not need changing. It's the first time I've worked slightly under the car so has also been useful learning how the axle stands and chocks work etc and I find it all quite enjoyable (if not a little stressful at first when dismantling just hoping no complications arise).

You are right about them being shims - I'll know for next time but until/unless they squeal then I'll just ignore that.

Can't say I've ever had a torque wrench nor not been able to undo a wheel nut by kicking the normal supplied wheel brace hard, standing on the same wrench to tighten while doing a little dance on it seems to tighten it enough fo4r it not to come undone - I've never had a loose one when it comes to undoing them. I think a breaker is less effort and cost than finding someone to admit they tightened it too hard and then to refuse to loosen it as it's dangerous or whatever. I'll see what I can find.

Appreciate your comments and help.
 
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d215yq

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have to say following.
1) garage stated corroded brake hose, i suspect they mean a corroded brake pipe (the metal pipe that connects to the rubber brake hose) check all your pipes, and if corrosion is not that bad, clean up and paint.
2) a 1 meter breaker bar would be your best friend along with your socket set to get the wheel bolts undone. They also need to be tightened to correct torque after re fitting. I breaker bar is quite a cheap item, a torque wrench a bit more money.


Re point 1), they've used the spanish word for deteriorating rubber (equivalent of glazed/surface cracks) and written the spanish word for hose so I don't think it could be a pipe as you would describe it as corroded/rusted and not "glazed/cracked". That said they've used the same for the rear tyres (other garage/MOT said they're fine) and also the V belt which has very minimal cracking. Possibly just covering themselves but I'll inspect the front ones properly when I get the wheel off

Which brings me to point 2) I think that's a good idea, I'll pick one up when I'm next in the DIY store.

Thanks
 

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