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 > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-18-2010, 04:15 PM
Registered User
 
Join Date: Dec 2000
Location: Bridgetown, Nova Scotia
Posts: 553
90 300S starting hard all the sudden.

I have a 300 S and when I brought it out of storage it started right up and ran fine, when I jumped in to go for a spin I stepped on the gas and she coughed and stalled. I had quite a time getting it going again but when it did go it would do the same thing. I managed to get it too the gas station and put in some high test thinking bad gas but almost never made it back. If I let it sit awhile it will start and idle but when I try to rev it up quick it will stall and be very hard to start after that. I will say it was working perfect when I put it away last fall. Anyone know where I could start to look? I will mention I think the alternator is not charging as the ABS is on and it tests as only putting out 12.6V. The low charge condition should not effect the engine running properly or would it? I have a new Voltage regulator to try to see if it is that or the Alt. itself.

Reply With Quote
  #2  
Old 07-18-2010, 06:26 PM
Registered User
 
Join Date: Aug 2002
Location: Southeastern PA
Posts: 3,052
Remove the voltage regulator and compare the length of the brushes with the those of the new voltage regulator. Worn brushes prevent the battery from recharging properly.
__________________
Fred Hoelzle

Last edited by Ferdman; 07-19-2010 at 05:10 AM.
Reply With Quote
  #3  
Old 07-18-2010, 07:09 PM
Registered User
 
Join Date: Dec 2000
Location: Bridgetown, Nova Scotia
Posts: 553
You mean by all means it will keep it from running properly? I have removed it and the brushes are worn out so I will replace the VR
Reply With Quote
  #4  
Old 07-19-2010, 05:18 AM
Registered User
 
Join Date: Aug 2002
Location: Southeastern PA
Posts: 3,052
Yes, if the battery is not recharging the engine will not run properly.

While driving our 1991 300CE several of the dash warning lights came on simultaneously and the engine started to run poorly. A short time later the engine simply died. Jumping the battery would permit the car to be driven a few miles until the engine died. Turned out the voltage regulator brushes were worn down to nubs preventing the battery from recharging adequately.
__________________
Fred Hoelzle
Reply With Quote
  #5  
Old 07-19-2010, 05:36 AM
Registered User
 
Join Date: Dec 2000
Location: Bridgetown, Nova Scotia
Posts: 553
I will let you know what happens when I change the VR
Reply With Quote
  #6  
Old 07-19-2010, 07:45 AM
Cal Learner's Avatar
Registered User
 
Join Date: Aug 2006
Location: Marysville, CA
Posts: 781
Fred, it is certainly correct that worn VR brushes will have the effect you described and keep the engine from running right. But the reason for that isn't that the battery is not being recharged (which is true), but rather that the engine isn't getting sufficient electrical power from the alternator to keep it running. A low battery is merely another symptom of that condition. Isn't that it, or have I misunderstood that all these years?
__________________
1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't
Reply With Quote
  #7  
Old 07-19-2010, 01:03 PM
Registered User
 
Join Date: Aug 2002
Location: Southeastern PA
Posts: 3,052
Cal, you are correct, but I didn't want to complicate matters. I recall disconnecting the battery in my 1972 Chevelle with the engine running, and it stayed running because the alternator output satisfied the engine's electrical needs.

__________________
Fred Hoelzle
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 01:02 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, 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