Brake pedal excessive travel
Thread Starter
Newbie
Joined: Dec 2021
Posts: 3
Likes: 2
S430, W113 280SL, 220d, W114 250, 300E
Brake pedal excessive travel
My 2000 S430 started having excessive brake pedal travel and in conjunction, the anti-lock 'thinks' the wheels are locking when they are not, anytime I push the pedal about halfway in this long travel. Normally with this much brake pedal travel, I would expect the master cylinder. But the ABS malfunction adds another element. This makes the car impossible to stop quickly as the ant-lock kills the foot pressure on the pedal. Any suggestions on what component to investigate initially?
Senior Member
Joined: Apr 2019
Posts: 428
Likes: 96
From: Houston
001 s600, 94 sl600
A good diagnosis with SDS is essential to finding the failed component in this case. You should not just throw new parts at it. There are several systems that interact in the brake system and cause such failures.
Thread Starter
Newbie
Joined: Dec 2021
Posts: 3
Likes: 2
S430, W113 280SL, 220d, W114 250, 300E
Which brings up a bleeding question ... See next
Thread Starter
Newbie
Joined: Dec 2021
Posts: 3
Likes: 2
S430, W113 280SL, 220d, W114 250, 300E
Continuing exploration:
We just installed a new master, as a Mercedes master-tech suggested the symptoms could be that of an internally by-passing master. When we bled the right front caliper, we got a constant stream of fine air bubbles which do not stop. Yet when we close the bleeder and step on the brake pedal there is no brake fluid leak, and we are not losing fluid. Yet we continue to have a soft brake pedal. Any ideas on this? Someone said rather than old-school bleeding, we need to power bleed.
Which brings up another question, in power bleeding, should one push the fluid down from the reservoir to the calipers or up from the calipers to the master?
We just installed a new master, as a Mercedes master-tech suggested the symptoms could be that of an internally by-passing master. When we bled the right front caliper, we got a constant stream of fine air bubbles which do not stop. Yet when we close the bleeder and step on the brake pedal there is no brake fluid leak, and we are not losing fluid. Yet we continue to have a soft brake pedal. Any ideas on this? Someone said rather than old-school bleeding, we need to power bleed.
Which brings up another question, in power bleeding, should one push the fluid down from the reservoir to the calipers or up from the calipers to the master?
