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 > Mercedes-Benz SL Discussion Forum

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 11-26-2009, 07:44 PM
violinr
 
Join Date: Apr 2008
Location: Horse cave
Posts: 27
Red face 450sl transmission rear seal failure

Any ideas as to why my auto tranny seal has twice blown out?
Neither time was it over filled, or being mistreated,,,correct seal for the transmission....last night coming back from the mechanic's it blew approx. 5 miles from the shop when it down shifted from 3rd to 2nd....my mechanic is stumped,,,and so am I...any thoughts would be appreciated!
Reggie
Reply With Quote
  #2  
Old 11-26-2009, 08:10 PM
Werner W's Avatar
Registered User
 
Join Date: Oct 2008
Location: Hudson Valley NY
Posts: 73
Did you check your VIN with the classic center to find out if you need a left handed seal or a right handed seal?


















Just kidding......
Reply With Quote
  #3  
Old 11-26-2009, 08:17 PM
violinr
 
Join Date: Apr 2008
Location: Horse cave
Posts: 27
Ha-ha!.....we even used adhesive to help insure it's staying in....still blew out as if under too much pressure.
Reply With Quote
  #4  
Old 11-27-2009, 09:56 AM
Gurunutkins's Avatar
Certified Idiot
 
Join Date: Oct 2005
Location: Seattle WA
Posts: 496
Werner is probably not joking
I just replaced both rear axles on my 450sl and the seals on both were handed unless you can get the upgraded part. the actual shaft itself has small threads machined into it to return oil from between the seal and the bearing back through the bearing. if you use the wrong one it actually pumps oil into the space. I bought new upgraded shafts without the thread so it didnt matter which seal I used. Here is the relevant bit out of the 107 bible. EPC seems to be down at the moment so I cant check it for the transmission seal but if you have an older car with the treads on the shaft (and I cant check for now) you may have a problem if using an aftermarket seal (right size number or not)
Attached Thumbnails
450sl transmission rear seal failure-seals-rear.jpg  
__________________
61 Austin mini
67 Lotus 7
74 450sl
76 Cadillac 8.2l (501 ci)

some new cars

megasquirt conversion on:
djet 74 450sl http://www.mercdjetmegasquirt.britautorepair.com/
cis 76 450sl http://www.merccismegasquirt.britautorepair.com/

the best view is always from the point of no return
Reply With Quote
  #5  
Old 11-28-2009, 06:31 PM
violinr
 
Join Date: Apr 2008
Location: Horse cave
Posts: 27
Thanks!,,,,after doing a very long search, I have found that there are 2 different seals for the 722.004 transmission,,,one is smooth and and one is handed...the one that blew out first was smooth and the one I replaced it with was also smooth,,,so,,,,I'am going to order the handed seal (both are the same size) and see if that fixes the problem...I would have never known as 95% of the parts houses carry the smooth one only.
Reggie
Reply With Quote
  #6  
Old 11-28-2009, 06:48 PM
Gurunutkins's Avatar
Certified Idiot
 
Join Date: Oct 2005
Location: Seattle WA
Posts: 496
hope that is the problem - simple fix. please let us know if it works
cheers
Barri
__________________
61 Austin mini
67 Lotus 7
74 450sl
76 Cadillac 8.2l (501 ci)

some new cars

megasquirt conversion on:
djet 74 450sl http://www.mercdjetmegasquirt.britautorepair.com/
cis 76 450sl http://www.merccismegasquirt.britautorepair.com/

the best view is always from the point of no return
Reply With Quote
  #7  
Old 11-29-2009, 07:39 AM
Werner W's Avatar
Registered User
 
Join Date: Oct 2008
Location: Hudson Valley NY
Posts: 73
Geese I thought I was joking. Well hopefully my joke put you on to the solution to your problem. GOD works in mysterious ways.
Good luck!
Reply With Quote
  #8  
Old 12-12-2009, 10:42 AM
violinr
 
Join Date: Apr 2008
Location: Horse cave
Posts: 27
Hi,
WE replaced with the other (handed seal)...It blew while still on the lift!...
I'am going to try and find a good transmission ...anyone close by have one?
Reply With Quote
  #9  
Old 12-12-2009, 11:25 AM
Registered User
 
Join Date: Sep 2008
Location: West Hills, CA Northwest San Fernando Valley, Los Angeles
Posts: 187
Dare I say the "D" word ?
Reply With Quote
  #10  
Old 12-12-2009, 11:30 AM
violinr
 
Join Date: Apr 2008
Location: Horse cave
Posts: 27
My mechanic as well as myself have already said several "choice words"...
Reply With Quote
  #11  
Old 12-12-2009, 12:11 PM
Gurunutkins's Avatar
Certified Idiot
 
Join Date: Oct 2005
Location: Seattle WA
Posts: 496
I really thought that might be it - I would be onto choice words by now as well.
good luck and if you disassemble it let us know what the problem was - there just should not be that much pressure at the seal.
good luck
Barri
__________________
61 Austin mini
67 Lotus 7
74 450sl
76 Cadillac 8.2l (501 ci)

some new cars

megasquirt conversion on:
djet 74 450sl http://www.mercdjetmegasquirt.britautorepair.com/
cis 76 450sl http://www.merccismegasquirt.britautorepair.com/

the best view is always from the point of no return
Reply With Quote
  #12  
Old 12-12-2009, 01:08 PM
Registered User
 
Join Date: Sep 2008
Location: West Hills, CA Northwest San Fernando Valley, Los Angeles
Posts: 187
No, the "D" word I meant, the one no one on the forum says with a smile. DEALER!

Might be a better choice before a Transmission replacement?
Reply With Quote
  #13  
Old 12-12-2009, 01:34 PM
Registered User
 
Join Date: Sep 2008
Location: West Hills, CA Northwest San Fernando Valley, Los Angeles
Posts: 187
HI Again, Now to be serious.what did you have done at your mechanic before the seal leaked or blew out.? The transmission has an internal pump that moves the fluid along and out to the trans cooler which is part of the radiator. None of these can bring pressure up to that level unless you have gotten air into the lines which does compress and can build up pressure. I think that you might want to look in other places before you do another seal. Best of luck J.
Reply With Quote
  #14  
Old 12-13-2009, 08:02 PM
violinr
 
Join Date: Apr 2008
Location: Horse cave
Posts: 27
the seals that have blown is all that I have had him look at other than make sure the vent part was venting / no bent lines....probably cheaper to just put in a good used tranny...and then tear the old one down and repair/rebuild for a spare.
Reply With Quote
  #15  
Old 12-13-2009, 11:00 PM
cth350's Avatar
Registered User
 
Join Date: Dec 2000
Location: Long Island, NY
Posts: 3,788
there are specs posted in the TDM for governor pressure and the like. Check those, if nothing else to eliminate any concern for the transmission internals.

On the mechanical front, are you sure the tailshaft diameter is correct? Perhaps it's scored or out of round?

There's a fellow in the vintage and parts for sale areas actively discussing rebuilding a transmission. He has a spare that he's been pulling parts from. See if you can get his spare tail shaft. Or at least, get him to mike it and compare the numbers to yours.

-CTH
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 11:11 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, 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