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 10-09-2013, 11:05 AM
Registered User
 
Join Date: Feb 2011
Location: Elverson PA
Posts: 42
500SEL dead

Guys I need some diagnosis help asap. Driving the '85 500SEL home the other day it just died on the road, no funny noises or anything just dead. Jumpered the FPR and checked the OVP and still nothing. I have spark going into the distributor cap but no spark at the plug wires. Brand new BOSCH rotor and cap about 6 month ago. Measured resistance through cap and rotor, both at about 1100 ohms, total of 2200 ohms before you get to the spark plug, which doesnt seem to high to me. I'm baffled and need to get this thing on the road by next week. Looking for any ideas.

Reply With Quote
  #2  
Old 10-09-2013, 11:15 AM
GemstoneGlass
 
Join Date: Dec 2005
Location: Northern,Ca
Posts: 882
make sure the rotor is turning

It could be a timing chain issue. Hopefully not. You could make sure it is turning by grabbing the rotor while someone is cranking. If the rotor still turns your chain is intact, but not necessarily in time.
Do you feel compression when you crank the engine. If there is a problem there the engine will turn very fast while cranking because of low pressure.
Your issue is definitely close to being figured out since you have determined spark is going to but not out of the distributor.
__________________

Chris
84 280sl
82 300d euro
Reply With Quote
  #3  
Old 10-09-2013, 11:29 AM
Registered User
 
Join Date: Feb 2011
Location: Elverson PA
Posts: 42
I did think of possibility of chain slip but it doesn't seem to turn any harder by hand than it did any other time I worked on it. If the chain slipped, wouldnt I have heard something when it died? I suppose a compresssion test would reveal if thats what happend.
Reply With Quote
  #4  
Old 10-09-2013, 11:39 AM
Registered User
 
Join Date: Aug 2013
Posts: 7
Did you pull the distributor cap and look underneath? Could be a problem with the inside of the cap, the rotor, or the distributor itself.
Reply With Quote
  #5  
Old 10-09-2013, 12:00 PM
Registered User
 
Join Date: Feb 2011
Location: Elverson PA
Posts: 42
yes I pulled the cap and cleaned everything last night. Even moved the motor to tdc and realigned the rotor to be centered on the mark where number 1 wire is supposed to be.
Reply With Quote
  #6  
Old 10-09-2013, 12:56 PM
JamesDean's Avatar
Electrical Engineer
 
Join Date: Apr 2005
Location: NE Ohio
Posts: 5,038
not sure if it will help but...

I would disconnect the coil from the dist..connect one side of an ohmmeter to the coil plug on the dist...and connect the other to an end of a spark plug wire lead...I'd rotate the engine around and see if the ommeter registered a completed connection being made. That way you would know if your rotor is connecting the coil to the plug wires..

Maybe bad ground or something of that nature?
__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k
Reply With Quote
  #7  
Old 10-10-2013, 06:58 AM
Registered User
 
Join Date: May 2004
Location: Natchez MS and Dallas TX
Posts: 355
Quote:
Originally Posted by JamesDean View Post
not sure if it will help but...

I would disconnect the coil from the dist..connect one side of an ohmmeter to the coil plug on the dist...and connect the other to an end of a spark plug wire lead...I'd rotate the engine around and see if the ommeter registered a completed connection being made. That way you would know if your rotor is connecting the coil to the plug wires..

Maybe bad ground or something of that nature?
There is no direct connection in the distributor. The spark jumps the gap between the rotor and the plug wires so an ohmmeter will not show anything.
__________________
85 300 SD ~ 115K
82 500 SEC Euro ??K
78 450SL 164K
Reply With Quote
  #8  
Old 10-10-2013, 08:04 AM
Registered User
 
Join Date: Nov 2004
Location: Dallas, TX
Posts: 5,134
[QUOTE=jhertzler1103;3220355]I have spark going into the distributor cap but no spark at the plug wires[/QUOTE

If no spark coming out of the any plugs or wires, then it's either your cap or rotor. Doesn't matter if you replaced them, this is where the failure is.

If it was a timing issue or anything else, you'd still get spark at the plugs.
__________________
With best regards

Al
Reply With Quote
  #9  
Old 10-10-2013, 09:28 AM
Registered User
 
Join Date: Jan 2003
Location: Matthews, NC
Posts: 1,356
I agree with alabbasi. The problem has to be in the dist. My guess is the rotor. I have never seen it on a Mercedes but we have seen a problem like this on many cars and trucks over the years. The rotor develops a hole from the center button location to the distributor shaft. It can be seen if you look very carefully inside the rotor where it sits on the shaft. It will be a very small dark spot. This is usually caused by a bad plug wire.
Keep in mind, as you are trying to start the engine the fuel system is still working which will flood the engine unless you have removed the fuel pump relay or something to stop the fuel pump. BTDT.

Good luck
Paul
__________________
84 500 SEL (307,xxx miles)
Reply With Quote
  #10  
Old 10-16-2013, 11:06 AM
Registered User
 
Join Date: Jan 2003
Location: Matthews, NC
Posts: 1,356
Did you find the problem?

__________________
84 500 SEL (307,xxx miles)
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 05:40 AM.


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