I just got a new fuel filter. I was planning to unscrew the old one (which is situated in the front of engine) and put the new one in. My concern is - would there be any major diesel fuel drop coming up from while doing the replacement? Should I do the replacement differently?

PAT
1999 E300TD 51k

There are two filters. Yes, you will loose fuel. I hope you have the o-rings to do this job, if not, your car may not run when you are done.

These engines are weird...Beware the DIY.

I wasn't aware that 2 filters are present. The picture below
show the location of the old filter and the new filter (made by Bosch in Spain - part number 1 457 434 123). The filter has 2 gaskets (should I call them o-rings?): the small one has an ID of 12mm and an OD of 21mm, the larger one has a ID of 61mm and an OD of 70mm. Is there another gasket (o-ring) which needs to be changed as well?

[url="http://208.55.38.244/images/fuel filter.gif"]

Pic (http://208.55.38.244/images/fuel filter.gif)
 

The url for picture is correct. Somehow I couldn't manage to load it into the actual mail message.

Been there, done that. The O-ring warning was very valid. I bought a new E300d in '96 and when it came time to replace the filters, I didn't put an o-ring on the prefilter. I'm sure that I ran 100,000 miles of life off of my starter before I figured it out. That was obviously before I found Mercedesshop.

Good luck,

The filter I have is the regular filter or the prefilter (as per your reply)? (see picture in previous posting)
PAT
1999 E300TD 51K

After I changed the fuel filter and the o-ring of the prefilter the engine doesn't start. Do you have any advise?