Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
HomeAnnouncements
Discussion Groups
By Brand
BMWChevroletDodgeFordGMHondaLexusMercedes-BenzNissanPeugeotToyotaVolkswagenOther Brands
By Topic
4x4 CarsRVsDrivingMaintenance & RepairCar AudioCollectible Cars
Country Specific
Australian ForumsUK Forums
ArticlesAuto InsuranceBuyingCars & TechnologyMaintenanceMiscellaneousSafety
DMV Resources
Related Topics
MotorcyclesBoatsMore Topics ...

Car Forum / Mercedes-Benz Cars / April 2007

Tip: Looking for answers? Try searching our database.

Brake Pedal Sinks

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
Rick - 11 Apr 2007 23:02 GMT
1984 500 SEL. I replaced a rotor on the passenger rear wheel, and
whenever I drive, if I press the brake pedal down at just the right
distance, the pedal slowly sinks to the ground, all the way. And when
Im stopped at a light, it slowly starts to sink down to the ground.
Any ideas?
-->> T.G. Lambach <<-- - 12 Apr 2007 00:32 GMT
I. Air within the new caliper. Did you bleed it after installation and
is the bleeder at or near the top of the caliper?

II. Low brake fluid level and / or defective master cylinder.

Signature

© 2007 T.G.Lambach. Publication in any form requires prior written
permission.

Rick - 12 Apr 2007 03:10 GMT
I didn't replace the caliper, its the one that was on there before,
the only thing I replaced was the rotor.
-->> T.G. Lambach <<-- - 12 Apr 2007 04:19 GMT
OK, when you replaced the rotor did you support the caliper or let it
hang by the brake line? If the latter I'd suspect the flex hose and
replace it if there's any doubt for the alternative, brake master
cylinder is more costly and therefore should be the second suspect.
Signature

© 2007 T.G.Lambach. Publication in any form requires prior written
permission.

Tiger - 12 Apr 2007 16:03 GMT
It is most likely your master cylinder is bad. I suggest you not drive the
car anymore unitl you get new master cylinder. You will find it at one time,
it will sink like crazy and you can't stop... unless you pump... but still,
you don't want to be in that situation.
Rick - 12 Apr 2007 19:35 GMT
The caliper was resting on something, not hanging. Ill check that flex
hose. It doesn't leak fluid though, at all.
-->> T.G. Lambach <<-- - 12 Apr 2007 21:28 GMT
The hose should be OK, go to the master cylinder.
Signature

© 2007 T.G.Lambach. Publication in any form requires prior written
permission.

Stupendous Man - 13 Apr 2007 06:44 GMT
If the line is undamaged, the master cyl piston got some crud in it when
retracting the pistons. Replace it.
Just out of curiousity, why change only one rotor? They cost under $30.
Signature

Stupendous Man
Defender of Liberty, Advocate of Justice

Rick - 13 Apr 2007 07:34 GMT
Long Story. Basically my wheel fell off one day, and it stripped the
threads on the hub. So I had to helicoil the threads, and the new
bolts were long enough to strike the parking brake mechanism.
Overtime, it broke off inside the rotor, and slowly scraped the inside
of the rotor. This eventually caused it to weaken enough until it
cracked. So I just removed the parking break mechanism on that wheel,
and replaced the rotor, and now I don't have any problems.
weelliott@gmail.com - 13 Apr 2007 14:39 GMT
> Long Story. Basically my wheel fell off one day, and it stripped the
> threads on the hub. So I had to helicoil the threads, and the new
[quoted text clipped - 3 lines]
> cracked. So I just removed the parking break mechanism on that wheel,
> and replaced the rotor, and now I don't have any problems.

That is except for the problem that you don't have a parking brake on
one wheel, which would be nice to have if your brakes fail, which
might happen if your master cylinder decides it doesn't want to play.

Please fix it correctly for everyone's safety, not just your own.
Tiger - 13 Apr 2007 15:03 GMT
Get the right lug bolt...  doesn't the factory lugbolt fit? Unless someone
put in the wrong one. Stick it into the wheel and look at the back side...
it should extend like 1" nothing more than that... if more than one inch,
then it is the wrong bolt and yes, will damage the parking brake.
Rick - 13 Apr 2007 16:57 GMT
Well they didn't have the right metric size helicoil, so I couldn't
use the original bolts. By the end of the month, Im having the hub
replaced with a used one, so it will be original
Tiger - 13 Apr 2007 22:19 GMT
Ahh... I see now... okay. Just be careful when you drive.
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2009 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.