Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 09-20-2009, 02:33 PM
tyl604's Avatar
Registered User
 
Join Date: Feb 2008
Location: Atlanta, GA
Posts: 3,633
Hot wheel - replaced back brakes yesterday

It was raining yesterday and I was driving my 81 300SD. Stopped at a gas station and noticed a slight burning smell near the rear wheels. Touched the right back wheel - OK. Touched the left back wheel - it was noticeably hot even after driving in rain. So I figured maybe the brake pad had completely worn through and the metal backing was scraping on the rotor and creating heat.

Not so. When I pulled the left rear wheel I found one almost new pad and one about half gone. It was very difficult getting the worn pad out, even using a heavy duty C-clamp to depress the piston. Finally broke it loose and then slowly pushed it in flat. I guess this side of the caliper was not releasing when I let off the brake. Sprayed blue no squeak on the new pad backs and slid them in. Then did the other side. Other side was pretty hard to depress too but not as bad.

So both sides are done. I have been having a lot of squeaking at braking but I assumed it was the front pads. Have not driven it yet but will be interested to see if the squeak goes away.

I had actually noticed that the left rear bundt had developed some black areas that would not come out with wax (I repainted them about 18 months ago and they are beautiful). So I now know that the wheel was overheating and that caused the black spots on the bundt.

Anyone know if you are still supposed to burn in a new set of pads and if so should you do it on the rear wheels which do not catch the brunt of the action when you stop?

PS - I still love this car; it is so easy to work on. Cannot say the same for my Land Rovers.

Reply With Quote
  #2  
Old 09-20-2009, 02:49 PM
oldsinner111's Avatar
lied to for years
 
Join Date: Nov 2008
Location: Elizabethton, TN
Posts: 6,243
I've had that problem.Calipers get sticky,and pads don't unlock. You can carefully work pistons out and clean,an press in.Lube all silding areas for pads.This will get you by a couple of years ,untill you can buy new rotors,calipers,and brake lines.I use only NAPA parts.
__________________
1999 w140, quit voting to old, and to old to fight, a god damned veteran
Reply With Quote
  #3  
Old 09-20-2009, 02:52 PM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by tyl604 View Post
When I pulled the left rear wheel I found one almost new pad and one about half gone.

I guess this side of the caliper was not releasing when I let off the brake.
What did you do to address the sticking caliper problem?
Reply With Quote
  #4  
Old 09-20-2009, 03:00 PM
tyl604's Avatar
Registered User
 
Join Date: Feb 2008
Location: Atlanta, GA
Posts: 3,633
Actually I have just assumed that it would start working again. Guess I better keep an eye on it.

Are you saying I should remove the caliper, take it apart, and lube the pistons? For about another ten minutes effort couldn't I just rebuild the caliper?
Reply With Quote
  #5  
Old 09-20-2009, 03:05 PM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by tyl604 View Post
Actually I have just assumed that it would start working again.
That is possible, if the brake pad was the cause of the problem. If the worn pad was just a symptom of the problem, more work needs to be done.
Reply With Quote
  #6  
Old 09-20-2009, 03:56 PM
Registered User
 
Join Date: Sep 2001
Location: central Texas
Posts: 17,281
UH.... many people do not have the tools to take apart the caliper with its pistons , get it back together then BET THEIR LIVES ON IT....
many manuals say to replace ( by axle ) the calipers if they need repair.
Reply With Quote
  #7  
Old 09-20-2009, 06:51 PM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by leathermang View Post
UH.... many people do not have the tools to take apart the caliper with its pistons , get it back together then BET THEIR LIVES ON IT....
Replacing caliper piston seals is hardly a "tool intensive" evolution. If the discussions on this forum were limited to the tools and ability of the least capable participants, they would be limited to checking the oil and replenishing windshield wiper fluid.

Quote:
Originally Posted by leathermang View Post
many manuals say to replace ( by axle ) the calipers if they need repair.
The MB manual for the subject vehicle contains detailed instructions on caliper "overhaul."
Reply With Quote
  #8  
Old 09-20-2009, 07:02 PM
oldsinner111's Avatar
lied to for years
 
Join Date: Nov 2008
Location: Elizabethton, TN
Posts: 6,243
To unstick pistons you find wood same size or a little under.The thickness of rotor and pads.Have someone hand push brake pedal.Clean around piston with toothbrush and wd40.If only one piston comes out,you press that until other one comes out.then clean and lube.Take pins and pad locators and clean road gunk with steel wool and wd40.
__________________
1999 w140, quit voting to old, and to old to fight, a god damned veteran
Reply With Quote
  #9  
Old 09-20-2009, 07:12 PM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by oldsinner111 View Post
Clean around piston with toothbrush and wd40.
The use of petroleum-based products on brake components is highly NOT recommended.
Reply With Quote
  #10  
Old 09-20-2009, 07:26 PM
Registered User
 
Join Date: Feb 2008
Location: DFW area (north side)
Posts: 1,288
Calipers or life insurance

Quote:
Originally Posted by leathermang View Post
UH.... many people do not have the tools to take apart the caliper with its pistons , get it back together then BET THEIR LIVES ON IT....
many manuals say to replace ( by axle ) the calipers if they need repair.
x2 But if you want to take the risk, you can buy life insurance for less than the cost calipers - your family might thank you.

I had one that was sticking but not as bad as yours. I replaced two - same axle.
__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/mercedes-benz-cars-sale/296386-fs-1-owner-83-mb-300d-turbo-rebuild-parts.html
Reply With Quote
  #11  
Old 09-20-2009, 07:40 PM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by Cr from Texas View Post
x2 But if you want to take the risk, you can buy life insurance for less than the cost calipers - your family might thank you.

I had one that was sticking but not as bad as yours. I replaced two - same axle.
Just curious, did you replace your brake hoses at the same time?
Reply With Quote
  #12  
Old 09-20-2009, 10:44 PM
Registered User
 
Join Date: Feb 2008
Location: DFW area (north side)
Posts: 1,288
Yes

Quote:
Originally Posted by tangofox007 View Post
Just curious, did you replace your brake hoses at the same time?
Yes! Even cheaper insurance.

I might take a short cut on things to make it go but not on things to make it stop.
__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/showthread.php?t=296386
Reply With Quote
  #13  
Old 09-25-2009, 03:43 PM
tyl604's Avatar
Registered User
 
Join Date: Feb 2008
Location: Atlanta, GA
Posts: 3,633
Well, it looks like the problem is solved. My wheel no longer heats up during driving. And the tremendous squeal each time I hit the brakes went away.

Thanks for the comments guys.

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 01:31 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page