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Discussion Starter · #1 ·
Hello everyone,
I have been psyching up, LOL, lately regarding major maintenance on my mb and this time , it's the brake system. I know that it's more major than my tranny change , last month, and so here I am asking for guidance from the gods.
How difficult is it and will there be any dont's while working on it, especially regarding computer stuff on the system ? Will I see codes later on especially when I hook it up wrong ?
Please advice. :confused::bowdown:
 

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Hello everyone,
I have been psyching up, LOL, lately regarding major maintenance on my mb and this time , it's the brake system. I know that it's more major than my tranny change , last month, and so here I am asking for guidance from the gods.
How difficult is it and will there be any dont's while working on it, especially regarding computer stuff on the system ? Will I see codes later on especially when I hook it up wrong ?
Please advice. :confused::bowdown:
The W210 is Easy to replace the BRAKE Pads...Simple remove and reinstall also replace the wear sensors...No Bleeding required but its a good idea to flush the brake system every two years!
 

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The wear sensors are very simple items and should not pose a problem. There are also ABS sensors at each wheel that you don't want to break, but these also should not cause any trouble.

In the old days, we would simply withdraw some fluid from the master cylinder reservoir and push the pistons back. With ABS, you should probably not force fluid from the caliper back through the system, and should loosen the bleed screw to extract the fluid when you reset the pistons. A brake fluid flush may be a good idea too, while you have the wheels off.
 

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Discussion Starter · #4 ·
Thanks guys.
One more question with pushing the caliper piston. I do not have to open the cap at the filler, just loosen the bleeder, is that correct?
 

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Thanks guys.
One more question with pushing the caliper piston. I do not have to open the cap at the filler, just loosen the bleeder, is that correct?
I followed gregs's DIY and its pretty easy. I don't know what you mean by cap at the filler, just open the bleed screw and push the piston back in. stick a little hose like from an aquarium on the bleed screw and you can guide it into a container. you want to be sure to add some fluid and then bleed each one you open after your all done. as ohlord noted if you dont change rotors then use some emery cloth on them to break up the glaze.
 

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Discussion Starter · #6 ·
Thanks people ,
So off I go to Autohausaz.
 

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I'm not so sure than you cannot just do it the 'old-fashioned' way, that is just open the filler cap and push the piston back. I've never done it the bleeder screw way on any of my cars (current and previous Mercedeses included) and never had problems.:surrender: I'd be more worried about getting air into the system with the bleeder screw method.
 

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I'm not so sure than you cannot just do it the 'old-fashioned' way, that is just open the filler cap and push the piston back. I've never done it the bleeder screw way on any of my cars (current and previous Mercedeses included) and never had problems.:surrender: I'd be more worried about getting air into the system with the bleeder screw method.
You certainly can push the pistons back, the old-fashioned way. But before you do, check the price on the ABS pump.
 

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I'm not so sure than you cannot just do it the 'old-fashioned' way, that is just open the filler cap and push the piston back. I've never done it the bleeder screw way on any of my cars (current and previous Mercedeses included) and never had problems.:surrender: I'd be more worried about getting air into the system with the bleeder screw method.
Technically you can do it any way you want. And you're right, you can almost be assured of getting air in doing it the way the DIY recommends by cracking the bleeder screw (if you're sneaky there are ways to avoid it, but it's like ten minutes when you're all through to bleed out what little air might intrude).

And if you take meticulous care of your car and flush the brake fluid at least as frequently as MB says, you lessen the chances of experiencing a nightmarish problem. But ... if you never push the fluid backwards through the system, your chances of it are exactly zero.

That said, once you've doubled your work time because you had to replace (or disassemble and rebuild) expensive system parts (like an ABS unit or a master cylinder) because of pushing old, degraded, contaminated fluid back through those little orifices -- just to save ten minutes of bleeding -- I can pretty much promise you it's nothing you'll want to experience again.

Take care and enjoy the ride,
Greg
 

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If the

rotors are anything but perfect renew them,autohausaz.com
if good deglaze them.
want less dust?Akebono pads from tirerack.
follow the bed in procedure.
:bowdown:
 

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Discussion Starter · #11 ·
You certainly can push the pistons back, the old-fashioned way. But before you do, check the price on the ABS pump.
Mat,
Do you mean if I do the old way , I have a chance of ruining the abs ?
 

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I recently replaced my front pads. I opened the bleeder at the caliper and slowly and steadily pushed the piston in. Then, immeadiately closed the bleeder. No air got into the system as I made sure that the fluid was coming out of the bleeder right up to the time that I closed it. Worked perfectly. Much better than taking a chance on pushing old fluid back through the ABS system.
 

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secure

a clear tube onto the bleed screw and submerge it into a bottle 1/2 filled with fluid.That way no air can back into the system.Since brakes only come every few years why not take the time to properly pressure bleed them after the brake job is complete,the new pads and rotors and you pedal feel will love you for it:thumbsup:
:bowdown:
 

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Discussion Starter · #15 ·
I strongly commend this forum for excellence and perfect assistance to people like me . Thanks, you guys. May we all be rewarded in heaven ! LOL !
 

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Greg/Matt,
Of course I frequently make the mistake to assume that everybody does always keep lubrication/brake/fluids related internals meticulously clean. ;) For the people that does not, your method may be marginally safer. The reason I say marginally is that in the event of a lockup, the ABS system pumps brake fluid upstream (BACKWARDS toward reservoir). See http://www.mercedestechstore.com/pdfs/327_traction_and_braking/327%20HO%2002%20ABS%20(WJB,GC)%2002-25-04.pdf

So if your brake fluid is dirty, you should better refrain from locking up your brakes. :)

One of my concerns with the bleeder method is the fluid used to top up the reservoir. I firmly believe that different types of fluid should not be mixed, and unless you have purged the system yourself, there is no guarantee about the make/lot nr of the fluid in the system. And if you fill up from an old bottle left over from the last purge, you are probably introducing a lot a water into the system. On my own car, I only open the reservoir when I purge the system or when I change brake-pads, about 2 times in the life of the brake fluid.;) I don't ever top up the reservoir, because I've never had the need to. I even discard the unused fluid from the opened bottle. The reservoir is designed big enough that it will not go too low due to pad wear. So if it goes below minimum, there is a leak somewhere.

All that said, this is the wonder of the Internet - all the contrasting opinions that can be found. :D And the greatness of democracy and free will - each one can make up his own mind as to what procedure works for him and ACCEPT responsibility for his own decisions. :D:D

So to paraphrase Greg: Take care and enjoy the brake (break :eek:) :D
 

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Greg/Matt,
Of course I frequently make the mistake to assume that everybody does always keep lubrication/brake/fluids related internals meticulously clean. ;) For the people that does not, your method may be marginally safer. The reason I say marginally is that in the event of a lockup, the ABS system pumps brake fluid upstream (BACKWARDS toward reservoir). See http://www.mercedestechstore.com/pdfs/327_traction_and_braking/327%20HO%2002%20ABS%20(WJB,GC)%2002-25-04.pdf

So if your brake fluid is dirty, you should better refrain from locking up your brakes. :)
Well, there is a substantial difference in the micro-milliliters of fluid cycled back and forth at the ABS unit itself and the several ounces of fluid shoved back by compressing a piston into a caliper (which is also why you have to siphon fluid from the MC if you're pushing it back). I've also seen clean fluid at an ABS unit and disgusting degraded stuff at a wheel cylinder/caliper.

As I noted, you only have to make this error once before you vow never to do it again -- or to suggest that others do it. There is little that feels worse than spending 45 minutes changing pads on one axle and jumping in the car to find a brake pedal that falls to the floor again...and again...and again. Lots more work and having to find alternative transportation until you can get the car fixed because of a "shortcut" are not things most people enjoy. With all due respect, Kobus, IMHO you've been lucky thus far, albeit luck combined with a bit of return for proper maintenance intervals otherwise. But personally luck is something I don't like to rely on, and if I must do so, I try to reach it only after experience and knowledge have already exhausted themselves.

Thus, while my typical mantra is "maintain your car as you see fit" there are exceptions, and this is one that begs for the exception. Even if I flushed my brakes every year I would never, ever compress a piston back into a caliper without cracking the bleeder valve and flowing the garbage out that way.

Take care and enjoy the ride,
Greg
 

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2012 C300 Sport 4Matic and 2003 CLK430 Cabrio
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OMG!!

:eek: I have done brakes on every car that I have owned for the last 20 years and have always used the big c clamp to push the caliper in. Now after reading this I'm very nervous about my next change.:eek: :confused:

All had ABS.
Toyota Supra
Acura Integra
Infiniti J30 t
Nissan 300Z
Nissan Maxima
Volvo V70
BMW 740
Mazda RX7 (No ABS)
Mercedes E430

This really worries me!

1) Has anyone here ruined the ABS pump by pushing it in?
2) Has anyone had to re bleed the brakes after cracking open the bleeder scree after the job was done?
 

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Hey, acarter. Aside from lots of anecdotal stories over the years, I have personally known a few people who have had to rebuild or replace an ABS unit and/or a master cylinder after compressing fluid back through the system. One was on some semi-exotic brand, I think the part itself was well over a grand -- dealer only of course -- and he also got to wait four weeks for the part (a car enthusiast with several nice rides, he was pretty anal about maintenance, so I'm guessing he was flushing the fluid regularly, I didn't ask since he was a little touchy on the subject at the time:rolleyes:). Personally, I will no longer force fluid back for a brake job even on a non-abs car after an event several few years back. I had a roommate with an older Civic, non-abs. He knew I knew something about cars (duh, I was often out in the garage tinkering on my car) and he asked about changing his front brake pads. Sure, I said, no problem, quick and easy, shouldn't take more than an hour.

Yeah, right. We compressed his pistons back in and guess what? No brake pedal; none at all. After I looked in the MC reservoir I could see why, fluid was dark and degraded. Went to the parts store and bought brake fluid, ended up flushing all of the lines and guess what? Still no brake pedal. This was on a Saturday, we would have had to wait until Monday to hit a foreign car parts shop to buy a rebuild kit for the MC. Instead, I removed and disassembled his MC, cleaning and soaking the cups in fresh fluid and lightly honing the cylinder and thoroughly flushing the orifices. The way I see it, I got lucky: that fixed it. In any event, instead of a quick hour job, it ended up being about 4-5 hours of work time, plus the extra brake fluid.

Can I put it another way? You do great work in basements/remodeling. If someone came and asked you about putting in shelving by using hollow-wall anchors in drywall of unknown thickness (rather than locating studs, etc.) to support shelves that they're going to use to display expensive and heavy glassware, what would you tell them? Yeah, you *can* do it that way, but...

Same thing here. You *can* do it the old-fashioned way. Again, on a properly maintained system you might get away with it, just like you might get away with hollow-wall anchors on shelves. But if you don't, the downside is pretty extreme. Even if the risk is only 10%, why take it? Why not reduce it to zero?

As noted, if you are very careful about doing the compression through the bleed screw, you won't introduce air into the system. But even at that, the best practice (again, reducing your risk to zero) is to spend ten minutes afterwards to make 100% sure there is no air in there. If you instead choose not to and it turns out your brakes are a bit spongy afterwards, you can still bleed them and you'll be fine (at least you'll still have brakes!). But in all honesty, isn't that infinitely better than taking the chance with the alternative?

Take care and enjoy stopping the ride,
Greg
 

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Hey, acarter. Aside from lots of anecdotal stories over the years, I have personally known a few people who have had to rebuild or replace an ABS unit and/or a master cylinder after compressing fluid back through the system. One was on some semi-exotic brand, I think the part itself was well over a grand -- dealer only of course -- and he also got to wait four weeks for the part (a car enthusiast with several nice rides, he was pretty anal about maintenance, so I'm guessing he was flushing the fluid regularly, I didn't ask since he was a little touchy on the subject at the time:rolleyes:). Personally, I will no longer force fluid back for a brake job even on a non-abs car after an event several few years back. I had a roommate with an older Civic, non-abs. He knew I knew something about cars (duh, I was often out in the garage tinkering on my car) and he asked about changing his front brake pads. Sure, I said, no problem, quick and easy, shouldn't take more than an hour.

Yeah, right. We compressed his pistons back in and guess what? No brake pedal; none at all. After I looked in the MC reservoir I could see why, fluid was dark and degraded. Went to the parts store and bought brake fluid, ended up flushing all of the lines and guess what? Still no brake pedal. This was on a Saturday, we would have had to wait until Monday to hit a foreign car parts shop to buy a rebuild kit for the MC. Instead, I removed and disassembled his MC, cleaning and soaking the cups in fresh fluid and lightly honing the cylinder and thoroughly flushing the orifices. The way I see it, I got lucky: that fixed it. In any event, instead of a quick hour job, it ended up being about 4-5 hours of work time, plus the extra brake fluid.

Can I put it another way? You do great work in basements/remodeling. If someone came and asked you about putting in shelving by using hollow-wall anchors in drywall of unknown thickness (rather than locating studs, etc.) to support shelves that they're going to use to display expensive and heavy glassware, what would you tell them? Yeah, you *can* do it that way, but...

Same thing here. You *can* do it the old-fashioned way. Again, on a properly maintained system you might get away with it, just like you might get away with hollow-wall anchors on shelves. But if you don't, the downside is pretty extreme. Even if the risk is only 10%, why take it? Why not reduce it to zero?

As noted, if you are very careful about doing the compression through the bleed screw, you won't introduce air into the system. But even at that, the best practice (again, reducing your risk to zero) is to spend ten minutes afterwards to make 100% sure there is no air in there. If you instead choose not to and it turns out your brakes are a bit spongy afterwards, you can still bleed them and you'll be fine (at least you'll still have brakes!). But in all honesty, isn't that infinitely better than taking the chance with the alternative?

Take care and enjoy stopping the ride,
Greg

Greg, I understand. It seems that the largest risk of opening the bleed screw is air in the system and that can be fixed right away. The old push the caliper in has a much larger risk. I will give it a try on the next pad change. I like olords suggestion of putting the tube in a bottle of break fluid to prevent air.
 
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