S212 Corroded Brake Line

[Cozen]

Hey everyone as mentioned I have a really bad corroded Brake Line. Which in hindsight don't seem bad to do ...but the brake line that's corroded is above the whole suspension and to do it looks like you have to drop the complete rear suspension and probably fuel tank to get access to it.

Wondering if anyone of you had come across this problem before??

 

[steveq]

It depends where the brake pipe is corroded.
If it is the area that is nearest to the wheel (and it normally is) then you could just cut out the corroded section, put in a new length and join it to the existing pipe.

 

[Cozen]

Thanks Steve I'm familiar with the pipe nearest to the wheel and wished it was...but where mine is corroded there's no access..I will see if I can take a pic this weekend when it's on the ramp

 

[190]

I'm surprised at the lack of response to your question as it's been a common enough problem on other models and there have been a number of threads on corroded rear brake lines. I imagine different models are similar in the brake line routing. On my W204 they come down the near side of the car under the trays and then behind the near side wheel arch liner. The line across to the offside rear wheel then goes up above the rear suspension. Mine failed the MOT on that exposed section and I had it replaced with cu-nickel as there is no point in putting the same crappy steel lines back in again. I would have done it myself but it would be near impossible without a proper lift. It's hard to see it never mine replace it.

 

[Cozen]

That's correct '190' it is hard to see let alone access... I had just serviced the bloody thing because I'm going away on a long 2 day driving trip. Fuel filter was a b**** to change but that's another story.

So if I was to undertake the job myself (I have a friend who can let me use his lift) am I right in saying whole suspension out, diff out and maybe fuel tank? Also I don't know how far back the brake line goes.

 

[190]

So if I was to undertake the job myself (I have a friend who can let me use his lift) am I right in saying whole suspension out, diff out and maybe fuel tank? Also I don't know how far back the brake line goes.

I quite certain the garage that did mine did not have to resort to dismantling anything other than removing the rear wheel arch liner but it's a different model. I think you will have to wait an see how it looks on the lift but I doubt you would have to do any of that. If what you are suggesting was needed, it would amount to outrageously bad design on MB's part.

 

[Londonscottish]

Good thread here with resolution

W212 E63 Rear brake lines | Wheels, Tyres, Brakes & Suspension

yes yes.. off that has to come.. did mine on the old clk, got a second hand rear subframe that was in excellent condition, removed the bushes etc and had it blasted and re coated. The brake pipes were a little bit worse than yours and I bought everything to replace mine back to good pipe, I got...

forums.mbclub.co.uk

 

[Cozen]

Good thread here with resolution

W212 E63 Rear brake lines | Wheels, Tyres, Brakes & Suspension

yes yes.. off that has to come.. did mine on the old clk, got a second hand rear subframe that was in excellent condition, removed the bushes etc and had it blasted and re coated. The brake pipes were a little bit worse than yours and I bought everything to replace mine back to good pipe, I got...

forums.mbclub.co.uk

Thanks Scottish,

Good thread here with resolution

W212 E63 Rear brake lines | Wheels, Tyres, Brakes & Suspension

yes yes.. off that has to come.. did mine on the old clk, got a second hand rear subframe that was in excellent condition, removed the bushes etc and had it blasted and re coated. The brake pipes were a little bit worse than yours and I bought everything to replace mine back to good pipe, I got...

forums.mbclub.co.uk

Thanks Scottish, wish mine was corroded at that location...and the corrosion on mine is worse then that!! I'll get some pics of it on the weekend. In the meantime I'll see if I can find the routing of the brake lines online.

 

[Cozen]

Worst than I thought it has leaking pipe underneath the tray .

 

[ChrisHGTV]

My Alfa is in the garage at the moment having the brake lines replaced. The fronts are effectively an engine out job so after a bit of discussion we’ve found an alternate routing that still looks neat. Might be an option to create a new route if access is that difficult on the Merc?

 

[Cozen]

My Alfa is in the garage at the moment having the brake lines replaced. The fronts are effectively an engine out job so after a bit of discussion we’ve found an alternate routing that still looks neat. Might be an option to create a new route if access is that difficult on the Merc?

It's an idea...but I have my head set on just cutting where the pipe is rusty and just doing the rears rather then complete from back to front to the abs module. Has to at least drop the subframe a bit and maybe fuel tank.

 

[Smiley]

MB brake pipe quality is shocking compared with other comparable manufacturers. The sad thing is that it would not cost much extra to improve the quality on the initial build whereas the cost to repair is relatively high. The cost of poor quality, they've known about it for years and chosen to do nothing.

 

[Londonscottish]

Worst than I thought it has leaking pipe underneath the tray .

Gah..

 

[Londonscottish]

MB brake pipe quality is shocking compared with other comparable manufacturers. The sad thing is that it would not cost much extra to improve the quality on the initial build whereas the cost to repair is relatively high. The cost of poor quality, they've known about it for years and chosen to do nothing.

Hate this sort of penny pinching shit. The non-removable non-return valve on my wife's Fiat 500 clutch assembly just failed. Had to replace the whole sodding assembly; the valve, the new lines, the reservoir. AND the slave. AND the sodding master! That lot plus VAT plus labour cost me north of £500. For the want of a £5 valve.

Grrrrr....

 

[Cozen]

Just an update. We lowered the subframe down a bit and managed to make new pipes from cupronickel. Went to bleed the car...the rear brakes can't be bled. There's slight little stream when you open the nipple. Tried gravity bleeding, using the launch to cycle the abs, bleeding at abs pump. Our mistake was all the brake fluid drained out the system overnight. Either there's trapped air or master cylinder. We going to try pressure bleeding it tomorrow.
Anyone else came across this before,?

 

[colinallcars]

Just an update. We lowered the subframe down a bit and managed to make new pipes from cupronickel. Went to bleed the car...the rear brakes can't be bled. There's slight little stream when you open the nipple. Tried gravity bleeding, using the launch to cycle the abs, bleeding at abs pump. Our mistake was all the brake fluid drained out the system overnight. Either there's trapped air or master cylinder. We going to try pressure bleeding it tomorrow.
Anyone else came across this before,?

Is the rear of the car raised? Could be the balancing valve has closed limiting the flow to the back brakes.

 

[Cozen]

Is the rear of the car raised? Could be the balancing valve has closed limiting the flow to the back brakes.

The car is on the ramp I've read somewhere on the forums that itcould be trapped air between the master cylinder and abs pump. We'll see my friend is gonna pressure bleed it today ...fingers crossed.

 

[jasonh]

Yes, someone else, I think on this forum, had immense problems bleeding the brakes after letting the system drain.

So for anyone else reading this job cap off the lines you're replacing:

Keep the brake pedal depressed (with a piece of wood and moving the driver's seat).
Disconnect the line at the ABS pump then cap off at the ABS pump with a spare flare and nut, and the line crimped.

However back to your immediate problem - MB say you have to pressure bleed and simultaneously pump the brake pedal.

 

[Cozen]

Thanks Jason car is sorted now I pressure bled it...without pump the brake pedal, thought I'll try without first. Loosened the 2 pipes from master cylinder. Lots of air came out. Thanks for everything everyone