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 06-24-2014, 08:52 PM
Registered User
 
Join Date: Jun 2014
Posts: 18
67 250S firing order

I've been looking for the firing order for my 67 250s with the carbureted 2.5L straight six. All I'm finding is Ford engine orders. I've worded it many different ways and still only Fords pop up. Does anybody have a diagram of the firing order?

Reply With Quote
  #2  
Old 06-24-2014, 09:11 PM
Registered User
 
Join Date: Feb 2011
Location: Modesto CA
Posts: 4,086
15, 36, 24

too young, too old, just right
Reply With Quote
  #3  
Old 06-24-2014, 09:36 PM
Registered User
 
Join Date: Jun 2014
Posts: 18
Quote:
Originally Posted by Frank Reiner View Post
15, 36, 24

too young, too old, just right
Okay I have the firing order correct then. Is there a certain starting point on the distributor? I can smell it getting fuel, all the grounds are good, and all the wires, plugs, cap, rotor, and ignition coil are new.
Reply With Quote
  #4  
Old 06-24-2014, 10:42 PM
Registered User
 
Join Date: Jun 2014
Posts: 18
Okay, so, the firing order is now correct, new plugs, new wires (fully secure), new cap, new rotor, new ignition coil, it's getting fuel, all the grounds are good, timing is dead on.

I noticed fuel is starting to pool around he carburetor next to the firewall. Not sure why.

It cranks over but it still seems to have no spark. All the fuses are good as are the relays.....I'm out of ideas....any help?
Reply With Quote
  #5  
Old 06-24-2014, 11:55 PM
Registered User
 
Join Date: Feb 2011
Location: Modesto CA
Posts: 4,086
Quote:
Originally Posted by Lo-Key View Post
Okay, so, the firing order is now correct, new plugs, new wires (fully secure), new cap, new rotor, new ignition coil, it's getting fuel, all the grounds are good, timing is dead on.

I noticed fuel is starting to pool around he carburetor next to the firewall. Not sure why.

It cranks over but it still seems to have no spark. All the fuses are good as are the relays.....I'm out of ideas....any help?
How has timing been determined to, in fact, be "dead on"?

If the coil wire is removed from the dist. and held ~1/4" from a ground, is there spark when the engine is cranked? If so, is there also spark at each of the plugs when cranking?
Reply With Quote
  #6  
Old 06-25-2014, 12:24 AM
Registered User
 
Join Date: Jun 2014
Posts: 18
Quote:
Originally Posted by Frank Reiner View Post
How has timing been determined to, in fact, be "dead on"?

If the coil wire is removed from the dist. and held ~1/4" from a ground, is there spark when the engine is cranked? If so, is there also spark at each of the plugs when cranking?
I had my neighbor come over and take a look at it when I first got it because he's been working on these for years and he said the timing is "dead on" so that's not the problem. He gave me a list of things to check before he left and I've gone over all of them.

I'll check the wires for spark again to be sure 100%. In the morning I'm going to rent a compression tester and see if that's the problem. The oil and coolant aren't mixed and I see no spots on the ground under the engine from leaks.
Reply With Quote
  #7  
Old 06-25-2014, 03:38 AM
Registered User
 
Join Date: Jun 2014
Posts: 18
Okay so I just tested the ignition coil plug wire and it give off a very very very faint spark. I also tried one that I know for a fact is good from my 72 because it ran before I pulled the engine and it did the same. So it's something with the spark not being strong enough.
Reply With Quote
  #8  
Old 06-25-2014, 09:02 AM
Registered User
 
Join Date: Jan 2003
Location: Matthews, NC
Posts: 1,356
From what I can find, the 250S has points/condensor type ignition system. Points not adjusted correctly or a bad condensor can cause weak fire from the coil. I have worked on many old domestic cars and trucks, but not on old Mercedes. Maybe some of the older forum members can chime in about these old systems.

Paul
__________________
84 500 SEL (307,xxx miles)
Reply With Quote
  #9  
Old 06-25-2014, 09:41 AM
Registered User
 
Join Date: Feb 2011
Location: Modesto CA
Posts: 4,086
Lo-Key:

The questions about spark quality were the first steps; now that you know that the spark is very weak, the next question is why. pmc has started you down that path; point cleanliness, correct gap, and condenser quality are some of the factors. Also, what is the voltage at the hot side of the coil, both with key on, and when cranking? This is a step-by-step process; there will probably be a few iterations.
Reply With Quote
  #10  
Old 06-25-2014, 12:07 PM
Registered User
 
Join Date: May 2009
Posts: 338
Quote:
Originally Posted by Lo-Key View Post
I've been looking for the firing order for my 67 250s with the carbureted 2.5L straight six. All I'm finding is Ford engine orders. I've worded it many different ways and still only Fords pop up. Does anybody have a diagram of the firing order?
I remember my old 220 firing order was stamped on to the engine block. Look for "zündfolge".

RayH
Reply With Quote
  #11  
Old 06-25-2014, 12:19 PM
is thinning the herd
 
Join Date: Mar 2010
Location: Columbus, Ohio
Posts: 3,339
It's generally on the valve cover.
__________________
68 280SL - 70 280SL - 70 300SEL 3.5 - 72 350SL - 72 280SEL 4.5 - 72 220 - 72 220D - 73 450SL - 84 230GE - 87 200TD - 90 190E 2.0 - 03 G500

Nissan GTR - Nissan Skyline GTS25T - Toyota GTFour - Rover Mini - Toyota Land Cruiser HJ60 - Cadillac Eldorado - BMW E30 - BMW 135i
Reply With Quote
  #12  
Old 06-25-2014, 05:09 PM
Registered User
 
Join Date: Jun 2014
Posts: 18
yeah I found it on the valve cover after I asked then felt stupid for asking haha.

I'll swap the ignition components from my 72 over to this one to see It helps any. I'll check back in after I do so to let you guys know if it's working or not. Thank you guys for he help so far.
Reply With Quote
  #13  
Old 06-26-2014, 11:22 PM
Registered User
 
Join Date: Jun 2014
Posts: 18
Alright.....so I swapped over the ignition coil, wires, and all the relays. Nothing changed. There's still only severely weak spark. I did notice though that the ignition coil is getting really hot. I accidentally put my arm on it and it burnt me.
Reply With Quote
  #14  
Old 06-26-2014, 11:44 PM
Registered User
 
Join Date: Feb 2011
Location: Modesto CA
Posts: 4,086
Lo-Key:

Suggest you re-read post #9.
Reply With Quote
  #15  
Old 06-27-2014, 05:26 PM
Registered User
 
Join Date: Jun 2014
Posts: 18
Quote:
Originally Posted by Frank Reiner View Post
Lo-Key:

Suggest you re-read post #9.
I checked the point this morning, it's burnt. I have to go back to the part store tomorrow and get another one again, they gave me the wrong one.

Reply With Quote
Reply

Bookmarks


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 03:40 PM.


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