Re: [MBZ] 124 Rear Calipers

2005-08-01 Thread ned kleinhenz
Thank you Peter.  Your advice makes sense.  If the pison stuck, can it
be fixed by replacing just the piston?  Or do just the o-rings need
replacement?   Is the cylinder of the caliper body usually OK?

I haven't looked at the front caliper yet. Does the front caliper have
a floating side?
Each rear caliper has two independent pistons.  Is there a caliper
rebuilding article somewhere?

Thanks, 
Ned

On 7/31/05, Peter Frederick <[EMAIL PROTECTED]> wrote:
> You need to rebuild the calipers, it's easy on this particular set (you
> can push the pistons back in by hand!).  Quick fix.  I would do the
> fronts as well, and check the condition of the pin and bushings the
> floating caliper slides on -- if they rattle or move sideways, replace
> them too (kits available).
> 
> I would also take a wire brush and clean up the bearing surfaces for
> the pads, they CAN stick if there is lots of corrosion in there,
> although that usually causes excessive pad wear rather than no pad wear!
> 
> I suspect what happened is that the calipers actually needed rebuilding
> last time the pads were replaced, so you have a pair of pistons that
> are stuck.  The rubber goes bad eventually, and although the caliper
> does not leak, you are not generating enough pressure to move the
> piston during normal use.
> 
> Working the piston free doesn't help, it will only stick again, or
> worse, leak.
> 
> Bad hoses cause BOTH pads to wear, not just one,  but I would replace
> all four hoses at 300,000+ miles anyway, they are MUCH cheaper than
> failed brakes!
> 
> Peter
> 
>



Re: [MBZ] 124 Rear Calipers

2005-08-01 Thread degcoast
I just had a caliper failure on a 123 and the hoses were not letting the 
fluid return so they held pressure on the calipers and thus the pads. Now 
with new hoses, the new calipers and pads are not sticking as they were when 
I put them on without changing the hoses at the time..


Dwight Giles
1979 240D auto 244k + miles
Wickford, RI
Bissell Cove Quahog & Auto Salvage Co.
- Original Message - 
From: "Kaleb C. Striplin" <[EMAIL PROTECTED]>

To: "Mercedes mailing list" <[EMAIL PROTECTED]>
Sent: Sunday, July 31, 2005 9:18 PM
Subject: Re: [MBZ] 124 Rear Calipers



sounds like maybe your brake hoses are bad and need to be replaced.
This is likely because you couldnt push the pistons in with hose hooked
up but could when you removed then.

ned kleinhenz wrote:


I found an unusual (to me) situation when replacing the rear brake
pads on one of my '95 E300D.  A dealer replaced the disks and pads at
some point just short of 300k mi, perhaps 2-1/2 years ago.  It's now
at 352k mi.  The rear brakes started  making noise, so today I started
replacing the pads myself.  When I removed the old pads on the left,
the outboard pad was gone and metal was rubbing the disk.  The inboard
pad was still like new and seemed to be siezed in the caliper.  The
right rear brake is in similar condition, but not quite as bad.  The
outboard pad is down to about 1/4 and the inboard pad is maybe at 3/4.

To sort this mess out, I removed both calipers.  There is no evidence
of leakage. And when I forced each pistion back (two per caliper) it
squirted fluid out the hose connections.  So the pistons don't seem to
be siezed.  But there is a lot of rust/corrosion around the pad guides
and pressure surfaces.  Has anyone else experienced this? What is the
source of this problem?  How do I correct it and avoid a repeat?  Can
I cleanup and rebuild the calipers?

Thanks
Ned Kleinhenz
'95 E300D x2
'85 300D
'80 300TD

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--
Kaleb C. Striplin/Claremore, OK
 89 560SEL, 87 300SDL, 87 300SDL, 85 380SE,
 85 300D,  83 300TD, 81 300TD, 81 240D, 81 240D,
 76 450SEL, 76 240D, 76 300D, 74 240D, 69 250
Okie Benz Auto parts-email for used parts

___
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For new parts see www.buymbparts.com
For repairs see www.oldworldauto.com

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Re: [MBZ] 124 Rear Calipers

2005-08-01 Thread Peter Frederick
You need to rebuild the calipers, it's easy on this particular set (you 
can push the pistons back in by hand!).  Quick fix.  I would do the 
fronts as well, and check the condition of the pin and bushings the 
floating caliper slides on -- if they rattle or move sideways, replace 
them too (kits available).


I would also take a wire brush and clean up the bearing surfaces for 
the pads, they CAN stick if there is lots of corrosion in there, 
although that usually causes excessive pad wear rather than no pad wear!


I suspect what happened is that the calipers actually needed rebuilding 
last time the pads were replaced, so you have a pair of pistons that 
are stuck.  The rubber goes bad eventually, and although the caliper 
does not leak, you are not generating enough pressure to move the 
piston during normal use.


Working the piston free doesn't help, it will only stick again, or 
worse, leak.


Bad hoses cause BOTH pads to wear, not just one,  but I would replace 
all four hoses at 300,000+ miles anyway, they are MUCH cheaper than 
failed brakes!


Peter




Re: [MBZ] 124 Rear Calipers

2005-08-01 Thread Kaleb C. Striplin
sounds like maybe your brake hoses are bad and need to be replaced. 
This is likely because you couldnt push the pistons in with hose hooked 
up but could when you removed then.


ned kleinhenz wrote:


I found an unusual (to me) situation when replacing the rear brake
pads on one of my '95 E300D.  A dealer replaced the disks and pads at
some point just short of 300k mi, perhaps 2-1/2 years ago.  It's now
at 352k mi.  The rear brakes started  making noise, so today I started
replacing the pads myself.  When I removed the old pads on the left,
the outboard pad was gone and metal was rubbing the disk.  The inboard
pad was still like new and seemed to be siezed in the caliper.  The
right rear brake is in similar condition, but not quite as bad.  The
outboard pad is down to about 1/4 and the inboard pad is maybe at 3/4.

To sort this mess out, I removed both calipers.  There is no evidence
of leakage. And when I forced each pistion back (two per caliper) it
squirted fluid out the hose connections.  So the pistons don't seem to
be siezed.  But there is a lot of rust/corrosion around the pad guides
and pressure surfaces.  Has anyone else experienced this? What is the
source of this problem?  How do I correct it and avoid a repeat?  Can
I cleanup and rebuild the calipers?

Thanks
Ned Kleinhenz
'95 E300D x2
'85 300D
'80 300TD

___
For used parts email [EMAIL PROTECTED]
For new parts see www.buymbparts.com
For repairs see www.oldworldauto.com

To Unsubscribe or change delivery options go to:
http://striplin.net/mailman/listinfo/mercedes_striplin.net





--
Kaleb C. Striplin/Claremore, OK
 89 560SEL, 87 300SDL, 87 300SDL, 85 380SE,
 85 300D,  83 300TD, 81 300TD, 81 240D, 81 240D,
 76 450SEL, 76 240D, 76 300D, 74 240D, 69 250
Okie Benz Auto parts-email for used parts



[MBZ] 124 Rear Calipers

2005-08-01 Thread ned kleinhenz
I found an unusual (to me) situation when replacing the rear brake
pads on one of my '95 E300D.  A dealer replaced the disks and pads at
some point just short of 300k mi, perhaps 2-1/2 years ago.  It's now
at 352k mi.  The rear brakes started  making noise, so today I started
replacing the pads myself.  When I removed the old pads on the left,
the outboard pad was gone and metal was rubbing the disk.  The inboard
pad was still like new and seemed to be siezed in the caliper.  The
right rear brake is in similar condition, but not quite as bad.  The
outboard pad is down to about 1/4 and the inboard pad is maybe at 3/4.

To sort this mess out, I removed both calipers.  There is no evidence
of leakage. And when I forced each pistion back (two per caliper) it
squirted fluid out the hose connections.  So the pistons don't seem to
be siezed.  But there is a lot of rust/corrosion around the pad guides
and pressure surfaces.  Has anyone else experienced this? What is the
source of this problem?  How do I correct it and avoid a repeat?  Can
I cleanup and rebuild the calipers?

Thanks
Ned Kleinhenz
'95 E300D x2
'85 300D
'80 300TD