Engine stumbles/dies while driving.... Help! - PeachParts Mercedes-Benz Forum

300EVIL · #1 03-23-2007, 05:32 PM

Hi Guys,
Being new to the whole Diesel thing, I need some more advice. Three days ago I took the Diesel for a spin. It drove fine until I downshifted and over-reved it a little too much. The engine immediately stumbled and died. From there i tried to start it many times. When trying to start, it would stumble and shake like it's only running on one cylinder. I eventually got it to keep running on "one cylinder" with about half pedal pressure. I let the engine idle like this until it cleared up and started to idle fine. From there I drove it home.

Today I drove the car about a mile and it did the same thing at the same intersection! It died, stumbled, eventually started and i drove it home.

The car starts and runs just fine but will just die while driving. My guess is it's some sort of fuel delivery problem. I just reciently replaced both fuel filters and also ran a can of diesel purge through it. Anyone have any ideas what specifically is causing this? Anything I should check?

You help will be greatly appreciated.
Thanks!
Adam

rrgrassi · #2 03-23-2007, 05:54 PM

Sounds like you may have air in the system. A little air bubble in the prefilter is normal. Check to see how full the perfilter is, and also make sure you bleed the system well after a filter change.

What do you mean by over rev? These cars with the OM617 would do higher RPM if the IP could keep up.

Also check to see if you get a "whoosh" when you remove the fuel cap on the tank. If you get the sound, then your cap is not venting properly and it's time for a new one.

Also check to make sure you have no fuel leaks. Check all lines, hoses, and the primer pump. Sometimes you can have an issue where air is being drawn in, but no visible fuel leak.

DeliveryValve · #3 03-23-2007, 05:59 PM

Are we talking about the '83 300SD?

I agree there sounds like air in the system.

Quote:

Originally Posted by rrgrassi

....What do you mean by over rev? These cars with the OM617 would do higher RPM if the IP could keep up......

I would say that 5,000 rpms is the maximum for these engines. I say at this point the engine could fly apart. The peak horsepower and torque hit well below that point.

300EVIL · #4 03-23-2007, 06:26 PM

Hey guys,
Thanks! All Fixed now! I "Assumed" I didn't have to pump it after taking the line off for the diesel purge because it ran just fine. I was obviously wrong. I pumped that thing for 2 minuites before i got diesel fuel. It obviously had a lot of air in there. I took it around the block a couple of times and it seems to run fine now.
Thanks Again!
Adam