Rough ideal after start - 1987 560SL

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Feb 25, 2022 | 09:04 AM
  #1  
Hello

Recently purchased R107 – 560SL from 1987.

Car is very original. Same owner for past 20 years.

I noticed two things:

1. Smell of fuel and..

2. Hard to start the car. After couple of trials the engine started, but the ideal is not smooth. It take a minute or two and once the engine get warm up and stable the ideal become much better.

Almost like normal.

So first thing, I found fuel leak. I replaced both fuel pump, Fuel filter and the fuel accumulator – all OEM. Now, there is no leak.

But the “hard start” remains and the same symptoms are there after start.

Your help and advice please.

Can it be the “Auxiliary air valve”?

Can it be the old and maybe the original injectors (car have 110k miles) that getting old?

I don’t want to waste money and time and replace the wrong parts.

Any thoughts and idea will be great appreciated.

Meir
Reply 0
Feb 26, 2022 | 08:19 AM
  #2  
Well, I'm pretty sure I'm not the first to complain this type of problem.
any other suggestion out there?
Reply 0
Feb 26, 2022 | 10:58 AM
  #3  
You could try some of the cheap solutions. Run a can or 2 of "Sea foam" or other injector cleaner through the fuel system, sometimes cruising in a lower gear so you get the RPMS up around 3,000 or so. You didn't mention if the car had been sitting for a while before you got it, could be old fuel, so dirve it and get fresh fuel in it.
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Jun 25, 2022 | 03:27 AM
  #4  
Hello, I know the problem, KE-Jetronic is for many a book with seven seals. I do many things myself and there are many instructions and videos on the net, such as the R107 screwdriver on YouTube: https://www.youtube.com/c/MercedesR107Schrauber/

Some videos also have English dubbing

The problems you describe can have many causes:

Defective pressure diaphragm
Defective cold start valve
Wrong air
Defective pressure disc potentiometer
defective or leaking electro-hydraulic actuator

Translated with www.DeepL.com/Translator (free version)
Reply 1
Jun 25, 2022 | 08:40 AM
  #5  
Looks like wonderful knowledge channel and learn How to, but a lot of the videos are in German :-(
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