Dies suddenly after good idling cold start

[geert1000]

It's all getting worse. I have made no linkage adjustments. (they seem correct as far as I've inspected).
I can't keep the car running at all now without the engine just totally cutting out dead, then recovering in spurts.
Is it possible that the spark is cutting out intermittently? I don't see condenser or coil failure symptoms in the tech manual on this site.
Can either of those go intermittent? Heck, is it possible that it may not be a fuel problem at all?
I've never had an off-timing or points exhibit this symptom. And I've not known what failing condensers or coils act like. Thoughts?

[garymand]

Troubleshooting this sort of problem takes great care, a checklist, step-by-step thorough checking of each thing we have suggested.  You need to one-by-one, eliminate as many of the items from the check list you can.  You need to help us help you. 

Make us a list, check them off.  Post the list, do each one.  Or, just take it to a mechanic and let them do it.  You can't successfully trouble shoot a complicated problem the way you are going at it.

To answer your questions, yes anything fuel or electrical is possible.  But sorry that doesn't help.  We can help you until you focus in on your problem.  

[geert1000]

You make a good point. I need to back up, making a list to check off all the items suggested.
Since I had just a short time to try things today, I couldn't even keep it running to try the open link mixture check more delicately.
So I got the wild idea to ask/suggest that it may be ignition, since the cutting out is so severe and total.
Again, I'll back up a bit and check off the suggested possibilities. Thanks again for the reality ck.
Geert

[Cees Klumper]

Have you replaced the spark plugs recently? And checked the rest of the ignition system (wires, ballast resistor, coil, points and so on). It still sounds ignition related to me. Also make sure the linkage brackets are all tight. I once forgot to tighten down one bracket and it caused rough running, which then fouled out the plugs beyond repair, even though they looked just fine.

[Iconic]

Okay, I finally got a chance to check a few more things and get symptoms with regards to my mid-warm-up running problem. (it's a "fully warmed up" problem as well)
1. My fuel volume is now measured at: 2 liters in 15 seconds, measured at the hose that enters the fuel filter.

This sounds like exactly what happened to me.
And, you are attacking it exactly as I did. I was looking for electrical problems and found none.
Measure your fuel flow at the point where the fuel returns to the tank.
If that is low, that will be your problem, a clogged return fuel line.
You can read my posts from 2009 if you like.
Mark

[geert1000]

Hello all, Since the car got to the point that it would barely run at all, I had to start over with the basics, check spark etc. I put a test light on the points and got spark again and again until, low and behold, all of a sudden no light! Even though I had previously cleaned and reset the points and verified spark, I now pulled them out and literally sanded/polished them, noticing that they, and condenser, are "after market" cheapies . I now re-installed and adjusted them again and, shazam! All my running problems are gone. Since the car's running deteriorated by degree after the initial points clean and set, I suspect a bad condenser may have caused extra arc-ing. (I've ordered a new Bosch set)
Perfect idle, plenty of smooth power, yahoo! Done. Thanks so much for getting me to run through and check the F.I. direction. I had already verified that the ignition was working, only to find out that it was an intermittent/by degree problem that would not show itself during static testing of the individual components. Thanks to all again!

[garymand]

Don't feel bad.  My 560 died 2 years ago.  1st thing I did was pull a plug to check for spark.  I saw a spark!  I know I saw a spark.  So, on to gas, volume and pressure.  Then to compression and leakdown. I discovered I had never changed the timing chain.  The chain had 250K on it.   6 months later I gave up.  But I don't live near any MB knowledgable mechanics and I'd have to have it towed.  I let the car sit while I got the W13 tip-top.  six months later I got my gumption back and said OK!  I know I have compression well within spec.  I checked Gas pressure and volume again and knew I had gas!

I pulled out 2 neon spark testers and put on on the coil and one on #1: nothing!  I took one light out and put it on the W113: LIGHT!  I felt like an idiot.  The big sedan had sat for a year and it was spark.  The coil primary had opened.  I have to believe, the coil put out one last spark before it died. 

[geert1000]

I actually don't feel bad at all. All and all a good experience! I was fooled by my static testing. Having gotten spark, I moved on and into an adventure in getting to know my car/systems. Also, let's all stick to factory (Bosch in this case) parts. The previous owner saved a few bucks but we now see, once again in life, that the right parts make a difference! I'm still thinking that a failing aftermarket condenser probably caused more arc-ing and accelerated points burning between cleanings.
This all brings me to the next question. Do most of y'all recommend electronic ignition conversion? If so, a particular brand? ( I've regularly converted my old Norton motorcycles this way through the years with great success)

[garymand]

Yes, I have an older 70's CD ignition, stock distributor and points.  Same points for 30 years.  I'm sure there are simple CD's out there but all I see are the mallory's with way too many bells and whistles and a high price.  But I have seen a breakerless point substiture that looks good.  Here is a good overview, but these points won't fit your distributor, it is a great overview of ignition realities.

I did find this: a point replacement.