[W126 Coupe] Brakes and air

[Ronny 560sec]

Just another idea about the brake problem.
Is it possible that the ABS system has to read the system to kick in.
Does it mean that the car has to run to find that out, because another guy told me he had that experience with a Ford.
I just was in the garage and sat behind the wheel. The brake pedal was very firm. I started the engine and put it in drive and the brake pedal get softer and went slowly down. When I started pumping the pedal came a little up.

Ronny



From: mbramel 
Sent: Sunday, December 19, 2010 12:57 PM
To: 'Mercedes Coupes Mailing Lists' 
Subject: Re: [W126 Coupe] Brakes and air


Couple years ago I had bought one of those mityvac units to bleed the brakes. First time I used it I guess I went a little overboard. Sucked all the fluid out of the lines. Then I filled the reservoir back up. Tried pulling the fluid through and I couldn't get anything? Tried the pumping method, that didn't work. And that took hours. Bought one of the motive bleeders from jegs for $50. Lines were done in 10 minutes for all four. Best $50 I ever spent. Good luck. Had to put a new MC on too because of all the pumping. But, looks like everyone has their own experience

 


--------------------------------------------------------------------------------

From: mbcoupes-bounces at mbcoupes.com [mailto:mbcoupes-bounces at mbcoupes.com] On Behalf Of Ronny 560sec
Sent: Sunday, December 19, 2010 2:54 PM
To: Mercedes Coupes Mailing Lists
Subject: Re: [W126 Coupe] Brakes and air

 

Jay H wrote:

Do not know why you  do not try the simple and fool proof way of bleeding lines

Jay, believe me we will try all the advices I received from  all at the mbcoupes.

I printed all the emails, also your 5 points of steps.

As soon as the problem is solved I will report that to you and all the others.

 

Ronny

 

From: Michael Ramay 

Sent: Sunday, December 19, 2010 10:58 AM

To: Mercedes Coupes Mailing Lists 

Subject: Re: [W126 Coupe] Brakes and air

 

The check valve in the middle of the 1/2" vacuum line from the engine to the brake booster is the normal failure point. Once that cracks/breaks and vacuum is gone, the pedal goes from the normal "kinda firm" to "Rock F'g Solid". A guy (LARGE guy) with both feet on the brake pedal *might* be able to get the car to stop. My 5'2" wife has no chance. 

FYI, this check valve is a part that should be looked at at least once a year to see if the plastic is starting to look chalky. Doesn't hurt to wiggle it a little bit too. IIRC, it's about $30 for the black tubing with the check valve in there.

On Sun, Dec 19, 2010 at 11:46 AM, Jay Hirsch <J.Hirsch at mac.com> wrote:

On "normal" cars,  to me which is  most American cars if the power booster  has  a "leak" the brake is very hard or firm,  and stays that way the more you apply pressure, something we all wish at various times
Will not comment on the 560  power booster but  assume all brake systems are the same....spongy pedal either air  in the line or fluid  leak some where.
Do not know why you  do not try the simple and fool proof way of bleeding lines

Jay H
On Dec 19, 2010, at 1:05 PM, Ronny 560sec wrote:

Jason,
I thought that when there is a vacuum leak the brake pedal will stiffen! Or am I wrong.
Meanwhile I will ask my mechanic to check that line too.

Ronny

 


--------------------------------------------------------------------------------

The MB Coupes Website!
W126 SEC Mailing List
Postings remain property of MB Coupes, L.L.C.



--------------------------------------------------------------------------------


The MB Coupes Website!
W126 SEC Mailing List
Postings remain property of MB Coupes, L.L.C.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.pairlist.net/pipermail/mbcoupes/attachments/20101220/2574b89f/attachment.htm>