240d keeps dying out after changing fuel filters - PeachParts Mercedes-Benz Forum

joegolden · #1 04-29-2013, 11:51 PM

So I changed both filters under the hood a week ago. I tried bleeding the air out with the pump and could not get much fuel in the clear filter. So I loosened the injectors and cranked the engine until I saw a little bit of fuel at all 4 injectors. She ran fine for a few days.

I took a drive this weekend and encountered a steeeeeeep ass driveway that I had to climb. A few miles down the road I lost power and coasted to a stop where she died and would not restart. I loosened injectors again and got her to run again. I drove 2 or 3 miles and repeat. I finally made it home and now I am afraid to go anywhere in it now. I let it run at idle for an hr today with no problems and actually drove a mile down the road before I chickened out and came home.

This was my first time doing this myself. Did I skip a step? What have I done?

barry12345 · #2 04-30-2013, 01:02 AM

Possible if the old primer pump is now leaking air into the system since it was used. Also the hose connections to the primary filter may be old and tired. Leaking air into the system since you changed the primary filter. New hoses and clamps should be installed if they are really old.

Diesel911 · #3 04-30-2013, 01:12 AM

You can buy some 5/16" ID Fuel Hose from an Auto Part Store and it is rated for Diesel for $6-$10 and replace the 2 sections of Fuel Inlet Hose.

If your Fuel Tank Screen is clogged and you have at least 1/2 Tank of Fuel you can check that by swapping the Positions of the Hoses where they come off the Tubing at the Fender Well.

When you do that you will be drawing Fuel From a higher positon in the Fuel Tank (why you need to have at least 1/2 Tank of Fuel) and you Return Fuel will be coming up through the Fuel Tank Screen.

It is also possible your Fuel is contaminated and contaminated Fuel can plug up a new filter fast.
Was there any Black or grayish-black-green substance in the Plastic Primiary Filter? If so you have something growing inside of your Fuel Tank and there is chemicals like Startron to deal with that.

toomany MBZ · #4 04-30-2013, 07:25 AM

Times two on the primer pump failing.

Fattyman · #5 04-30-2013, 11:55 AM

X3 on the prime pump.
Older type that unscrews? Yup.

Diesel911 · #6 04-30-2013, 01:16 PM

Another description. The Old Style Hand Primer has a bare Metal Aluminum Body and a hard Pladtic Knob at the top. The knob is most often white but some aftermarket ones have a had black Plastic Knob.

joegolden · #7 04-30-2013, 01:34 PM

It's a Bosch with a white knob that unscrews and and then pump. Is that original?

toomany MBZ · #8 04-30-2013, 02:07 PM

Probably, the new style (Bosch) has a black button, you don't need to unscrew it, just pump.

Merica · #9 04-30-2013, 02:16 PM

Yes that sounds like the old original primer pump. White knob, unscrews then pumps. They absolutely leak and need replacement. The only MB I bought with the original primer pump I replaced myself. Not hard to do at all. I think Mercedes Source has a video on it.

joegolden · #10 04-30-2013, 04:28 PM

It's a whites knob that unscrews...then you pump. I saw bergsma pump on one of his old w123 and it was a black button almost.. Thanks. She ran fine all day today with a full tank o fuel

LUVMBDiesels · #11 04-30-2013, 08:13 PM

I had to replace the original one on my '81 300SD. It was leaking air and when it wasn't leaking air it was leaking fuel. I parked the car on a hill facing up so when I pulled the pump not much fuel leaked out. If I recall there is one bolt that is a b****h to get out.

Diesel911 · #12 04-30-2013, 10:53 PM

Quote:

Originally Posted by LUVMBDiesels

I had to replace the original one on my '81 300SD. It was leaking air and when it wasn't leaking air it was leaking fuel. I parked the car on a hill facing up so when I pulled the pump not much fuel leaked out. If I recall there is one bolt that is a b****h to get out.

Did you remove the whole Fuel Supply/Lift Pump?

The Hand Primer Pump can be changed without removing the Fuel Supply/Lift Pump.

t walgamuth · #13 05-01-2013, 06:46 AM

If you have never used a biocide it is probably a good idea to do so in case there is bacteria clogging the tank strainer.

joegolden · #14 05-01-2013, 12:07 PM

I am going to run this tank down and then drain the fuel. I need to order the socket Kent has at mercedesource to get the strainer out...unless some one has a better solution..

Thanks t walgamuth I will certainly get some for my tank. I haven't put anything in it yet. Thanks

barry12345 · #15 05-01-2013, 05:11 PM

Strainer may be fine. Remove fuel line near tank to see if fuel will easily flow out. Actually with a full tank I think it will flow out even the front fuel line under the hood if disconnected.

If the problem is brand new right after you changed the fuel filters it is more likely to be something in the more immediate vicinity. There is always coincidence of course to consider but unlikely.