300D wont stay running
 

I need Ideas we replaced all of the fuel lines in the engine compartment as they were leaking. and put new filters. the clear filter was Totally Black when I changed it and the 2nd Filter was loaded with Crap like chunks of rust?

Primed the system have fuel at all of the injectors. it does start on it's own but will not stay running unless I have my foot on the gas pedal and it will run for less than a minute no matter how far down on the pedal I press and die.


Oh and it has this loud tick sounds like a really bad exhaust leak but louder. and by my muffler where the car has run the grass is now black. any Ideas?

I really miss my car I do have another benz here for parts but I do not know what parts I need.


Someone said to clean the injectors?? How would I go about that?
:(

1st thought is the tank screen, but if you have that much crud building up it may need a tank cleaning and/or replacement.

I'd guess the tank screen as well. Try switching the supply and return lines in the engine bay, or pull them off and put them both into a bottle of good clean fuel and try running that way. If the car runs normal than your tank screen to clogged.

300d
 

I would remove the primary filter and perhaps the secondary and check for rust/dirt and replace them. If still dirty perhaps filter in tank is clogged, too. It would probally be a good idea if you still see lots of contamination to drop the tank and clean it. You could also be sucking air or possible water in fuel. Always best to start with a clean slate. Good Luck.

If you are still having a problem after all the other stuff has been checked try driving with out the fuel cap on. If things improve it may be that your fuel tank vent is clogged.

It could be an air leak. With apparent fuel problems like this, I like to substitute a simple fuel system under the hood that bypasses most of the existing components. Take a soda bottle of clean diesel, run your input and return lines into the bottle, afix the bottle high enough that gravity will cause it to feed and see if the engine runs ok on this system. If it does, your problem lies somwhere in the fuel tank, lines,pump.

Good idea; how much fuel will he need to have in his fuel tank so that the fuel level will be above the fuel return stand pipe in the fuel tank?

You'll first need to confirm that both filters are free flowing before setting up the temp tank and checking if it runs ok from the temp fuel supply......sure sounds like the tank and filters are gunked up.

If you've got badly fouled inj you prob shouldnt run it too much until the tank gets cleaned out and the inj(s) repaired. Some risk of damage.

If its a minor inj tick, diesel purge may help.

the filters are not gunked up anymore I can see thru the 1st filter and the spin on one is also clear. if I disconnect the fuel line from the 1st filter it runs out like no tomorrow.

While it was running we pulled the first to injector lines off one at a time to try to isolate what injector and when we pulled the first 2 it ran even worse. so I assume it is not those 2 and also I have already tried running it without the gas cap on and still no difference. am I to believe I have a bad injector? The tick is really loud and very annoying.

One or two bad injectors won't keep the engine from running. I'm hopping on the "really cruddy fuel tank and/or tank strainer" band wagon. The procedure for cleaning the tank strainer has been written up here before and can be found pretty quickly with a search. You may need to buy a special 46 mm socket to do it, but no other special tools are involved.

Air leak in the fuel system? are there bubbles in the clear filter when runing? a bubble is OK, but not a flowing bubbles.

did you fill the screw on filter w/ fuel?


My car leaves its mark , too. my garage door has a nice sooty circle on it.

got any other injectors you can swap in? that could tell you something.

I would prolly drain the tank and try to clean it if it clogged up filters already. also flush the lines. if you got that much rust, a line could be bad? leaking air and killing car??

ladams, when you replaced the secondary fuel filter did you align the banjo bolt hole for best flow?

Align it how??? I missed that Memo Please explain.:confused:


Thanks,
Lind

Alternate theory:

When you disconnected the hoses to change the pre-filter, or perhaps the looping return lines, you may have bent them beyond the cracking point and they may now be permitting air entry into your fuel system, which will cause the car to stall out. I had the same issue the first time I changed the filters on one of my 300TDs a few years back- the old fuel lines were brittle and cracked when I bent them (though not visibly) and allowed air into my system- Replacement was an instant fix. Also, if you still have the screw-in primer pump, they can leak and allow air entry too. If not used for long stretches, the internals can become similarly brittle and break down when you finally get around to using them.

Also, if your car has a gas pedal, we can't help you. ;) An accelerator, on the other hand...

Good luck!

It won't be the first time. Check for vacuum to the engine shut off diaphragm. Sometimes the key switch will leak through while in the run position and sut down the engine. Just remove the vac line fron the shut off diaphragm. If it continues to run you have found the problem.