PeachParts Mercedes-Benz Forum - View Single Post - Proper fuel filter replacement procedure on OEM603

Jeremy5848 · #17 11-26-2009, 10:57 PM

As Brian said, getting a secondary filter into place when it's full of fuel is difficult without spilling. I used the "wedge" technique on the '96 E300D today and had no problem starting the engine. The same technique should work on other 60x engines. The 61x engines don't have the access problem so it's a lot easier to pre-fill the secondary filter and hold it in place while tightening the central bolt.

First, I removed the primary filter. After a year and 8,400 miles it was still clean (265,000 miles on the original engine). I moved the existing Viton o-ring (I use biodiesel) to the new filter and installed it.

Next, I removed the secondary filter and drained it into a container. The filter holds less than a pint of fuel; I'm sure there was still some left inside, soaked into the filter paper, but I didn't want to wait a week for it all to drip out. Since the fuel was clean, I planned to re-use it in the new filter.

I put the new, dry filter in place and loosely screwed in the center bolt to hold it in place. With the filter properly located, I used a couple of pieces of wood to wedge the filter up against the housing. This allowed me to remove the central bolt and insert a funnel.

Now I was able to pour the fuel that I'd drained from the old filter into the new one. I needed a few milliliters of extra fuel to fill the filter all the way to the top. To be on the safe side, I put a paper coffee filter in the funnel (not shown in the picture).

Once the secondary filter was full, I removed the funnel, replaced the central bolt, and buttoned everything up. The engine started immediately and I gave it a little extra throttle until I was sure it wasn't going to stall on me.

I plan to cut the secondary filter open with my Dremel tool so I can see what it looks like inside. I'll post a fifth picture when I get that done.

Jeremy