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So where is the actual leak at the MC ?
The interface MC to Brake Booster ? or somewhere else ?
Yes, thats exactly where, it was impossible to see, but the end of the MC was wet with fluid when I removed it, but luckily there's a seal at the brake booster.
Last edited by pierrejoliat; 09-22-2022 at 05:15 PM.
Pierre, good job re-plumbing all your lines!! You're not the kind that backs down when troubles ring.
Your experience calls for a thread to coat all the unprotected steel lines.
Many folks drive in the rust belt... I am in dry California.
Thanks Cali, but now that I have done it, I would be faster next time! And more aware just how time consuming it is! I know you'll be happy, I had a can of black rustoleum left from something, I did spray them! But they are Copper-Nickel so I don't know how effective it will be, LOL. Slow and steady wins the race, but I'm hurting today, got the wheels back on and went for a ride after my buddy came over to help with the bleed process, I used about a liter and a half of fluid.Finding the original leak was hard, it was only dripping when the brake pedal was pressed or in the hold function, go figure. But you guys helped immensely and I'm glad to share the accolades!
Glad to hear your diagnosis was correct, and you were able to fix it.
I can relate on the body aches from crawling under and around a car. Although I still enjoy doing my own car maintenance, there is a price to pay. But I worry that when I stop doing this kind of projects, the price on my body will be higher.
I have almost 130,000 miles and plan on taking a trip out west to see my daughter. Changing Regular Maintenance items for a 12 year old car with 130,000 miles is not unusual. Especially when you are going over 2,000 miles and are in bad terrain for a Mercedes-Benz dealer near by? I am 67 years old and last time I had my Benz in the Dealer for Service was 2017 at 90,672 miles on the last of 3 service plans I had when My Wife bought a service plan on it seeing I just hot done less than a year from Cancer treatments from Stage 3 Non-Hodgkin's Lymphoma losing 14.5 inches of my small intestine and 6 surgeries. I have done all the service since 90,672 miles. I am due for Transmission Service which I planned a month ago but spent 3 days in the hospital with Congestive Heart failure caused by the Chemo Drugs from 11 years ago. It seems every time I have time to work on My Mercedes-Benz E350 my Daughter's Lexus or My Wife's Audi Q5 needs something especially the Lexus RX350 with 183,000 miles on it. I know Pierre is trying to fix his Car but before buying it some parts do wear out and on a Mercedes it CAN be costly to repair especially if you cannot do some DIY maintenance?
OK you guys of great help, I have completed the brake line install from Anti-lock unit to rear wheels, Wow, took 21 hours to complete, but got all the lines back into all the retainers and connected, filled with fluid and no leaks so far! Have a friend coming today to help with the bleeding process and have everything back together but the wheels. I did take Left Coast Geek's suggestion and used Copper/ Nickel lines, not just because they last longer, but because they are way easier to bend than coated steel which was stock.
I think the bleeding will go well and look forward to getting the car off the jack stands and floor jacks, wheels on and get my wife out of my car, LOL. I bought two Liters of Dot 4+ so should have enough.
So just to recap, MC was leaking, but only under brake pressure, which is why it could sit without leaking for days at a time, the leak was so small and brake fluid so clear and thin that the booster did not look wet, it was not obvious at all and as earlier mentioned had no signs of malfunction, there was no fluid in brake booster, I lucked out there! I will update after the bleeding process and first ride around the block.
Also; I might suggest not doing this job on a garage floor or lift quite frankly if yo are as old as I am, I had plenty of room and a creeper to get around on, but I hurt all over! Also I want to thank all of you for your expertise and moral support, couldn't of done it without you!!!! And to Toledo Tom. thanks as well, without your comments I might have given up and taken it to my Indy, instead I saved like TWO GRAND in labor. Cheers
Amazing work, Pierre! Climbing under these cars on jack stands will beat you up. I've had the TR8 on stands probably 10 times and at least it's light enough to get up and down with my shop floor jack. I can't imagine doing what you did on that Mercedes. You significantly scared me with this brake work that I sold the E550 today. The used car market is still pretty good and I decided I have the Triumph to wrench on and other cars to drive around town. Retirement has diminished my driving significantly and I really need a more versatile vehicle, like a small pickup (not a 150K G-Wagon!) Living in a 120-year-old house requires constant trips to Home Depot.
Once again, Way to tackle that job head on!
Amazing work, Pierre! Climbing under these cars on jack stands will beat you up. I've had the TR8 on stands probably 10 times and at least it's light enough to get up and down with my shop floor jack. I can't imagine doing what you did on that Mercedes. You significantly scared me with this brake work that I sold the E550 today. The used car market is still pretty good and I decided I have the Triumph to wrench on and other cars to drive around town. Retirement has diminished my driving significantly and I really need a more versatile vehicle, like a small pickup (not a 150K G-Wagon!) Living in a 120-year-old house requires constant trips to Home Depot.
Once again, Way to tackle that job head on!
-Keith
Sorry to read that you've sold your E550, Keith. You've volunteered a great deal of information and help on the W212. Although we need no help with a TR8 (LOL) I hope you stick around and contribute from memory.
Amazing work, Pierre! Climbing under these cars on jack stands will beat you up. I've had the TR8 on stands probably 10 times and at least it's light enough to get up and down with my shop floor jack. I can't imagine doing what you did on that Mercedes. You significantly scared me with this brake work that I sold the E550 today. The used car market is still pretty good and I decided I have the Triumph to wrench on and other cars to drive around town. Retirement has diminished my driving significantly and I really need a more versatile vehicle, like a small pickup (not a 150K G-Wagon!) Living in a 120-year-old house requires constant trips to Home Depot.
Once again, Way to tackle that job head on!
-Keith
Thanks Keith, it was an epic undertaking, LOL. Sorry to hear about your loss, but I do understand, retirement changes our lives hopefully for the better, I've never been busier and don't know how I had the time to work! You've got a wonderful little car there, I remember lots of time working on mine with my kids when they were teenagers and driving them daily.I've put total of 700 miles on my '12 this year, much going to Home Depot! I could use something more utilitarian also, I'll keep the '12 and sell the '13 when the wife retires. You've also been a long-time great contributor to this forum, many, like me have greatly appreciated your contributions, I wish you all the best and hope from time to time you stop by and say hi to us here!!
Last edited by pierrejoliat; 09-23-2022 at 06:52 PM.
Glad to hear your diagnosis was correct, and you were able to fix it.
I can relate on the body aches from crawling under and around a car. Although I still enjoy doing my own car maintenance, there is a price to pay. But I worry that when I stop doing this kind of projects, the price on my body will be higher.
Thanks, I agree, gotta keep doing and moving, I'll be 64 this year and rolling around on a creeper is not the same as when I was 40!
Did you get to bleed air out of the ABS/ESP hydraulic unit ?
When I lost my fluid due to the plug coming off and at least 500cc or more brake fluid was lost, air got into my ABS/ESP hydraulic unit, lets call it HCU.
I assume you doing new brake pipes would be the same as my case, which is air introduction to the HCU.
Xentry is required to simulate an ABS pulsation.
I do not know what is wrong with MB Xentry designer, the menu title for ABS pulsation activation is SBC HOLD ... !! Dugghhhhh
Also why only LEFT side brakes, I do not know. It could be wrong description too by Xentry designer
Above actuation gets our pedal to pulse like a true emergency ABS activation and with the strong noise.
This one below turn on the motor, but I do not know if any of the 12 solenoids are open or not. No pulsation to brake pedal whatsoever.
This one below is only a mild CLICK, solenoid click
I had to bleed twice.
1st time I got on my LEFT FRONT caliper, micro bubbles so plenty, it looks like those nice foamy black beer Guiness Stout froth.
At first I thought my brake fluid was contaminated with some other "oil", I waited for like 60 seconds and all the micro bubble gone and brake fluid looks normal....wheeewhhhh.
2nd time was final after I ran 2 liters total on all 4 calipers, I got 2 big air bubbles still, from the FRONT LEFT.
My naughty Xentry for some reason is being naughty, it kept crashing after I did SBC Hold activation . So wasted time booting up the Xentry again and again.
The need for air bubble removal, caused to me do some reading.
I wanted to know where are the potential air pockets inside the HCU.
WIS for W212 has no hydraulic schematic, only electrical one for ESP/ABS.
So I looked at 2 generations ago, W210 which is what our W212 is using or 99% similar. The W211 SBC is not useable as a reference as it was different.
I believed the air pocket is at item 11 ( Low pressure accumulator ) which is probably no more than a few milliliters just enough to push each caliper's piston/s maybe 1mm only
Without actuating the SBC Hold ( ABS pulsation ), I also believe that the green zone I marked as OUTLET will store air pockets from y7 and y9 at least up to y22 and y23 ( ( A7/3y22 and A7/3 y23 ) Front or Rear Axle inlet solenoid/s.
I could be wrong on which circuit is INLET and OUTLET, but item 11 accumulator is commonly at OUTLET line and not INLET line.
I tried to compare W210 schematic which is a hydraulic schematic, to W212 which is Electrical Schematic to see common parts.
Attached original W210 and W212 documents too. ABR = Adaptive Brake , hhmmm so many unique terms.
Hope this helps if your HCU indeed has micro air bubbles.
Oh Surya, you're gonna hate this, I disconnected the battery and we bled the brakes! Took about a liter and a half, none of that was necessary, I pumped and held until I got zero bubbles then closed the bleeders. I have been driving the car for a week now, great pedal no warning lights or issues at all. My buddy who came over was a ASE verified master technician and had done a few of these before, so I felt comfortable doing it this way. I do have an Icarsoft MB2, but did not need it ,nor do I think it is capable of the process.
Last edited by pierrejoliat; 09-26-2022 at 06:17 PM.
Lucky you Pierre, that is good news
The bubble sensation I speak of is very very minute ( the one caused by 2 big air bubbles ), the first plenty of micro bubble froth was totally obvious.
Lucky you Pierre, that is good news
The bubble sensation I speak of is very very minute ( the one caused by 2 big air bubbles ), the first plenty of micro bubble froth was totally obvious.
Yes, when I was done I had pushed a whole Quart through the system, no bubbles solid stream
09-22-2022, 11:07 AM
. So wasted time booting up the Xentry again and again.
