My 85 300SD has been sitting for a couple of years, although I start it every couple of weeks. The idle was very rough, so last weekend, I performed a diesel purge. This really smoothed out the idle - I was amazed. The container with the purge remained clear during the whole process (2 cans of purge). After the purge, I removed the fuel filter, and the top of it was covered with rusty looking gunk with the consistency of solidified grease. I replaced both the canister filter and the pre-filter, and now get no fuel coming out of the injector pump. I removed the lines from filter to the pump and they have this same heavy grease like brownish gunk plugging up the fittings and the fuel lines. I wasn't able to remove the line from the primer housing to the filter, and pumping the primer doesn't pull any fuel into the pre-filter.

None of the gunk is pumped out of the injection pump, but the line leading to it was completely plugged up. I have cleaned the lines as best as I can, but I still don't have any fuel coming out of the injection pump. The fuel coming out of the supply line from the tank seems to be fairly clean.

I don't understand how the engine would run at all if the lines were this badly plugged up, or did the purge somehow force the gunk into the fuel filter and injection pump lines?

Any recommendations on how to clean the fuel lines out, and have I likely contaminated the injection pump?

I believe the previous owner did run vegetable oil from time to time, but it doesn't have any kind of special system for WVO.

Have you tried to bleed the fuel system? I believe there is a priming pump on the side of the pump for your engine.

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UK spec Mercedes W210 E300 Turbodiesel wagon - OM606.962 with 722.6 transmission - rust free!

Fill the big spin-on filter with fresh clean fuel, re-connect your temporary fuel tank that had the purge in it, fill that with fuel and elevate above the IP so gravity will help. Loosen all the hard injector lines at the tops of the injectors. Disable the glow plug relay temporarily (remove the 80 amp strip fuse). Crank the engine for up to 30 seconds at a time, while watching the injectors for fuel getting to them at the loose hard line, tighten up each injector hard line as you see fuel. Once you have all the lines tightened up, install the fuse and the car should start right up.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

If you are unable to pull fuel into the pre-filter, it is likely that you have a clogged filter screen at the tank or maybe a clogged line coming from the rear.

You may be able to pull the line at the tank and see if you are getting fuel there. Clamp the flex line with needle-nose vise-grips and disconnect it from the hard line. A quick, temporary release of the vise grips should let you know. Caution: don't take a diesel bath!

I shake my head at the thought but you may have to drain the tank and clean everything from the priming pump rearward to get fuel flow after unfiltered, unheated veggie. I believe kerosene or biodiesel are the better solvents for this.

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Sam

84 300SD 350K+ miles ( Blue Belle )

I did try to bleed it with the primer pump, but it doesn't seem to draw any fuel into the pre-filter. It is the old style primer.

When I crank the engine, I do get fuel coming out of the line from the tank. The same line I clamped off when I did the purge. I don't see any of the greasy crud in that line.

I will try that. The one fuel line that i can't remove because of lack of space to fit a wrench, is the one from the main filter housing to the injector pump. Thanks