arturo71

I've got a '97 E300D, 6 cylinder 3.0 liter diesel mercedes. It was running fine but won't run now. i changed the battery, and the engine turns over just fine. Put some fuel in the tank just to be sure.

I'm thinking it could be a clogged fuel filter, since I bought the car used and have no idea how well it was maintained.

Any other troubleshooting ideas?

Thanks

nelbur

Try a spare key. This car has a chip in the key that can fail, allowing the engine to crank but not fire. This car also can have an air leak into the fuel lines, and if parked on a hill nose up, the fuel runs back to the tank, making it hard to start.

arturo71

Aha, that makes sense...I did have the car parked on an incline in my driveway, nose up...most likely air in the fuel line, then.
So, how to remedy that?

Plutoe

If you don't want to look for the leak, then just have a spare battery available and crank and crank and crank until the air is purged!

Alternatively, have a neighborhood push party and reverse the direction of the car on the incline so the nose is facing downward!!

Hopefully by morning all the guests and beer bottles are off the lawn and the car will start.

nelbur

There are quite a few places that air can get into the fuel line up near the engine. If you had fuel related work done recently, like a fuel filter change, that would be the first area to check, but there are numerous O-rings on the clear fuel lines that could leak air. Unfortunately this engine is not equipped with a manual fuel pump, like earlier engines were. If you can roll it to where it is level, or better yet, so the nose is lower, you should be able to crank it enough with the starter to prime the system. Do not just crank it continuously, as you will kill the starter. I would crank it for 10 to 15 seconds, and walk away for 10 minutes for the starter to cool. Then repeat, until it starts. If you fill it up and park with the nose down, the place where the air was getting in will likely leak fuel, which might eliminate a lot of trial and error.

The reason I know this car has this problem is because my neighbor owned my car and parked it on a sloping driveway. I watched a roll back from a local shop pick up the car three times in a weeks time. After it disappeared for the third time, I asked him if he didn't want to sell it to me so he could get something reliable. When it came back he said they found an air leak, but he didn't know exactly what had leaked air. He had a newer Mercedes about a week later.

arturo71

thanks for the tip. I've seen a lot of videos on YouTube with older models that have the hand primer pump you are talking about. too bad mine doesen't have one!
Will keep trying.
thanks.