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I own 4 MB's- 89 300E, 89 560SEL, 86 SDL and a "Euro" 85 190E also have 84 Porsche 944
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Discussion Starter · #1 ·
Hello Benz lovers:
Greetings from Dallas!
I need help. I have a 1986 300SDL that has trouble starting the first time I crank it up. Usually that's in the mornings but it doesn't matter as long as it's been sitting for more tha 4 hours or so. It reads little over 295,000 miles on the odometer.
I have had a mechanic check the glow plugs because I suspected it may be needing new ones (I have had the car 2 years) since I have not replaced them but he said they are OK and he suspects that the problem is that fuel is somehow backing up to the tank and is not readily available when I crank the engine in the mornings. After a lot of cranking it starts up and after that, while is still hot, during the day it does start right away.
In doing research here I found a post from someone familiar with the Volkswagen Diesel cars and he said that they use a check valve in the tank that keep the fuel from going back and losing the pressure that was built up in the system by the pump.
However, he did not know at that time (2 years ago) if the Benz has the same check valve.
I believe this could be the reason the fuel is backing up to the tank.
One time, I parked the car overnight on an inclined driveway, with the tank at the lower end after a trip and the fuel was low. The next day I could not get it started at all. I had to have someone come over and work on it until the pump was able to suck fuel in again.
Do any of you know about this check valve? Does the 300SDL have one, if so where? Is it in the fuel tank or in the fuel pump?
And if they don't have it, any idea what the solution would be so I can get the engine started as it should?
Any help will be greatly appreciated.
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