Author Topic: Hot Start Issue - One More Issue Example - For the Records  (Read 2687 times)

Pawel66

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Hot Start Issue - One More Issue Example - For the Records
« on: September 08, 2018, 12:22:12 »
Just for future generations, in case someone is looking at hot start issue, which is fairly common - an issue and diagnosis.

The symptoms: difficult hot start. Car running ok, starting cold in 3 seconds after several weeks of parking, etc. Just would crank and not start when hot - neither after 10 minutes nor after half an hour.

The issue: restricted fuel supply through the main supply line.

How figured out: first was to look if spark plugs are wet or dry while cranking to try to start the engine. They were dry. Then measuring fuel flow right after the fuel pump and then at the main filter showed low flow at the fuel filter and a very good flow right after the pump. Could not detect it by blowing air through the line. Only by checking the fuel flow.

Hot start ok once the obstacle was removed. I will not write what the obstacle was, because everybody would laugh at me.

Note: for those who have the TTS replaced by the Bosch unit - please note it activates the CSD at all times, also when engine is hot (it just does it for different amount of time or just when cranking, depending on temperature). May consider not to depress gas pedal when starting or depress it just slightly.
« Last Edit: September 08, 2018, 20:30:07 by Pawel66 »
Pawel

280SL 1970 automatic 180G Silver
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W121 190SL
G-class

stickandrudderman

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #1 on: September 08, 2018, 18:47:47 »
Go on Pawel, tell us what it was! :)

Pawel66

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #2 on: September 08, 2018, 20:31:23 »
No way until several shots of vodka are drunk one day.
Instead I added a very clever piece I omitted before about dry spark plugs.
Pawel

280SL 1970 automatic 180G Silver
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W121 190SL
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mrfatboy

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #3 on: September 08, 2018, 21:07:16 »
Was it a fatberg???😜😜😜😜😜😜😜

https://en.m.wikipedia.org/wiki/Fatberg
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Tyler S

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #4 on: September 08, 2018, 21:27:53 »
Did you forget to take the plastic wrapper off the fuel filter?
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Mike Hughes

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #5 on: September 08, 2018, 21:37:21 »
I was thinking of something related to the fuel filter, or the lines connecting to the filter housing, too!  We've all done silly things, so you might as well tells us Pawel, inquiring minds are going to zero in on it eventually anyway! ;^)
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Pawel66

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #6 on: September 09, 2018, 07:27:17 »
Ok, I thought maybe for others to avoid it, although it is difficult to expect anybody would do something similarly silly...

I squeezed the soft part of the fuel line between fuel pump cover and the floor, applying too thick and soft rubber sleeve protector. I did not cut it, just squeezed it and did not notice...
Pawel

280SL 1970 automatic 180G Silver
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W121 190SL
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Shvegel

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #7 on: September 09, 2018, 10:27:03 »
I place a high priority on lighting in a shop for exactly that reason.  As I have aged there now doesn't seem to be enough light in the world for me.  I now have a very large bright LED panel abouve my work bay and a 4 foot long flourescent style LED for under the car.  I like the large format because it prevents shadows that you might get from a single small source. 
« Last Edit: September 09, 2018, 10:35:57 by Shvegel »

Pawel66

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #8 on: September 09, 2018, 11:43:14 »
Yes! Lighting was the cause!
That will be my story and I will stick to it!
Pawel

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A-230

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #9 on: September 09, 2018, 16:02:27 »
My long lasting warm start problem on my -64 disappeared when i set a pushbutton in circuit with the cold start solenoid. If it does not start in 2 secs I just push the button a bit of a sec, and it starts immediately, always.
Drive safely,
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Pawel66

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Re: Hot Start Issue - One More Issue Example - For the Records
« Reply #10 on: September 09, 2018, 16:24:11 »
This solution is used by many fellow Members and seems to be very effective. I think it compensates for the issues of the original TTS set up. I think the Bosch TTS replacement takes care of it as it activates CSD also at 80-90 degrees temperature range.

In my case this would not help as activating CSD has no effect as CSD was not getting enough fuel supply...
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class