fuel filter change - Page 3 - PeachParts Mercedes-Benz Forum

Hit Man X · #31 01-14-2005, 04:35 PM

Quote:

Originally Posted by P.E.Haiges

Hit Man X,

What is silly is to replace fuel filters that do not have to be replaced.

If it ain't broke, don't fix it also applies to fuel filters.

P E H

So you'd rather have a large problem on your hands as opposed to some PM? Sounds silly to me.

d.delano · #32 01-14-2005, 04:46 PM

Quote:

Originally Posted by Hit Man X

So you'd rather have a large problem on your hands as opposed to some PM? Sounds silly to me.

It seems PEH doesn't believe in PM. Might be a good philosophy for retirees looking to save money with a stable of several cars, but not for somebody with one car that needs their transportation to be there when they need it, like me.
For example, if my fuel filter plugged on Connecticut Avenue in the middle of rush hour traffic that would be a huge inconvenience. But retirees prefer to habitate in the middle of BFE due to the peace and quiet factor and the general slow speed of life and it wouldn't be such a pain in the neck to break down on the side of the road. So in that sense I understand where he is coming from. But for my part, 'an ounce of prevention is worth a ton of cure'>'if it ain't broke don't fix it'

andersbenz · #33 01-14-2005, 06:35 PM

I put this on the other fuel filter thread as well.

Recommend that diesel drivers keep a spare spin-on fuel filter and 22 mm wrench in their trunk. The filter in my `84 300D burst about ten years ago.

I was about an hour north of Bangor, Maine and was just able to get to Bangor International airport to rent a car before the fuel ran out and the airport closed. Of course, I had my manager traveling with me that day, and had to get him to Portland.

P.E.Haiges · #34 01-14-2005, 10:40 PM

Hit Man X,

Would you please explain how a dirty fuel filter can do damage to the engine since as a fuel filter becomes loaded with dirt particles , it blocks smaller and smaller particles up to the point where it will not pass the fuel molecules.

Why don't you change the Tansmission filter each time you change the transmission fluid?

P E H

Hit Man X · #35 01-15-2005, 12:11 AM

Quote:

Originally Posted by P.E.Haiges

Hit Man X,

Would you please explain how a dirty fuel filter can do damage to the engine since as a fuel filter becomes loaded with dirt particles , it blocks smaller and smaller particles up to the point where it will not pass the fuel molecules.

Why don't you change the Tansmission filter each time you change the transmission fluid?

P E H

Where did I say it would do damage? That's right I did not. Do not put words in my mouth. I was making a statement regarding your statement "if it ain't broke, don't fix it."

I see no reason to let the filters get so plugged to the point where they hamper performance or not allow the vehicle to get out of it's own way. Heck, the main inline filter is less than $2. Problems arise when you do not counter them before they occur.

Why about the trans filter? Well... trans filters by their nature are nothing more than a screen for the valve body to prevent metal filings (pretty normal) from plugging/jamming the valve body from performing it's normal functions. So when you turn your vehicle off all the metal drops to the bottom of the pan anyway. Run the vehicle for about 5 min then flip it off. Simply drain the pan and converter, then refill.

Do what ya want... I have a 190K mi 1996 LS400 that's my mothers that I do this sort of PM to and it runs like a top. Will I stop? Certainly not.

phantoms · #36 01-15-2005, 01:42 AM

I do see possible damage in the increased workload of the fuel system in trying to draw the fuel through clogged filters. I don't think that this means you should replace the filters as soon as you see a speck of dirt/fungus/etc., but when you noticed a fair amount (a good reason to use a clear primary filter) of it.

dannyF · #37 02-13-2005, 04:38 PM

Its great to read this discussion. I have been having the algae (actually, fungus, so I learned on this conference) for a couple of months in my '84 300 SD. Was told to clean out the tank, but have been working with BioBor (that I finally found easily in West Marine boat stores) and I am about to change the 2 filters.

I see nothing in the manuals about how to change (or clean) the fuel strainer. Can anyone point to directions on that (I searched this site but haven't found it yet). I must have stuff getting stuck there because my prefilter (which was changed 2 months ago) is looking clear still and I am starting to experience power loss again....

Also, I see a lot on the purge, but haven't yet found how to do it (but I am searching the site on that one too).

Thanks.

Dan '84 SD300

phantoms · #38 02-13-2005, 05:19 PM

Quote:

Originally Posted by dannyF

I see nothing in the manuals about how to change (or clean) the fuel strainer. Can anyone point to directions on that (I searched this site but haven't found it yet).

Try http://skinnerbox.steaky.org/Service/W123/w123CD2/Program/Engine/617/47-700.pdf. This gives directions for tank R&R for the 116 and 123 models. A diagram of the complete tank is on page four (116 model). I'm not sure if the 126 is the same, but the tank screener should be similar.

There is also a diagram of your fuel tank here.

P.E.Haiges · #39 02-13-2005, 05:49 PM

DannyF,

Use the search. I'm sure I posted how I cleaned my tank strainer. BTW I used an air hose with air nozzle for a mechanical cleaning when I couldn't find a solvent that would dissolve the fungus.

No need to remove the fuel tank. I used Biobor and only plugged one inline filter in 10,000+ miles. Don't make a lot of work for yourself by removing the tank when its not necessary. The Biobor will solve your problem.

Another thing, before you remove the strainer, test how much fuel comes out of the fuel line from the strainer. If its a good steady flow, the strainer is not plugged . If it just drips or a slow flow, strainer needs to be cleaned.

P E H

tangofox007 · #40 02-13-2005, 07:27 PM

Quote:

Originally Posted by Hit Man X

Why about the trans filter? So when you turn your vehicle off all the metal drops to the bottom of the pan anyway.

Cut a used one open some time and you might change your mind about that.

dannyF · #41 02-20-2005, 02:55 AM

Thanks, PEH and phantoms,

I've read the posts on the fuel strainer, but I didn't see anywhere the size socket wrench needed to remove the strainer on a Mercedes '84 SD300. I think it has to be a socket wrench owing to the small space I have to work where it comes out of the tank.

I am about to do the test you suggested to see how much fuel comes out of the line when it is taken off the strainer, but I am almost positive it is plugged with fungus, since I just replaced my filter and prefilter and still had power loss. I had used biobor a few weeks ago. It helped, but the problem came back. Added doses of biobor didn't help, but it may be because I refueled before adding the biobor and it didn't mix well. I am now trying to get my tank level down in case I need to empty it, so I don't want to put more fuel in again, so added doses of biobor don't seem to be helping because they may not be mixing.

In any case, I am prepared to remove and clean the strainer - I plan to either siphon or drain my half tank of diesel. All I need is the wrench size (the 1 1/4 inch one I bought is too small).

P.E.Haiges · #42 02-20-2005, 11:22 AM

DannyF,

Biobor will not clean the fungus out of the system, It just kills what fungus is in there so it doesn't continue growing. By the amount of Biobor you said you added, I'm sure all your fungus is dead, but still in the fuel system.

Your filters will get the dead fungus out of your fuel system, but you can expect to change them several times, especially the inline filter. I guess I was lucky, my inline filted plugged only once in my '80 300SD in over 10,000 miles since I added Biobor. So I figure all the dead fungus is gone by now.

Maybe I was lucky but I was able to remove the tank strainer by turning the 17mm or 19 mm nut on the fuel line connection to the strainer plug. Give that a try first as it is the easiest way and you don't need a special wrench. I don't see how it is possible to use a socket wrench to remove the strainer plug, if I remember correctly.

I cleaned the strainer by blowing the fungus out with compressed air. The dead fungus is like brown silicon rubber and I couldn't find anything that would dissolve it.

P E H

Brian Carlton · #43 02-20-2005, 11:31 AM

Quote:

Originally Posted by dannyF

In any case, I am prepared to remove and clean the strainer - I plan to either siphon or drain my half tank of diesel. All I need is the wrench size (the 1 1/4 inch one I bought is too small).

I wanted to do the same thing on the SDL. However, due to the slighly recessed position of the strainer, nothing but the actual socket would do the job.

The size is 46mm. A 1 13/16 socket will also work fine. The SDL had clearance problems and a socket that large (with 3/4 drive) would probably be too long for it.

I understand that the proper tool is a special, short, 46 mm socket with a 1/2" drive.

A wrench that large may also not be suitable due to limited room to swing it.

Good luck. If you do get it out via an alternate method, please advise.

Mister Byrnzoil · #44 02-20-2005, 01:51 PM

My prefilter would turn BLACK after less than a half-tank, so I took action.

I drained the tank, when I removed the hose from the bottom of the tank, the fuel GUSHED out, so the in-tank strainer is not clogged (or it has been compromised in some fashion) anyway, I filtered all of the fuel, and got lots of black gunk out.

I now have 2 primary filters in the fuel line, and I have been reusing the prefilters. I can't believe all the gunk that comes out of that tiny filter.

Am I the only one here cheap enough re use the primary filters?? I just rinse with simple green, gently blow it out and reinstall. (then 100 miles later its jet black again.)

I'm using a star-brite fungus enzyme, (the same one I use in my boat diesel) hopefully its doing its job.

Cheers,
Robert

dannyF · #45 02-21-2005, 12:21 AM

Hello Mister Byrnzoil and thanks to PEH and Brian C. for your comments.

In response to Mr. B.: I am not that experienced working on these cars yet, but your experience sounds similar to mine. Fuel gushed out of my line after the strainer, too. I stopped it back up because I have so much in the tank and I didn't want it all out at that point! I siphoned a bunch (7 gallons or so) of the diesel out through the fuel tank. That stuff looks real clean. The stuff that gushed out of the fuel line that I caught in my basin was black. I think I can re-use the stuff that I siphoned out (I'll treat it w/ biobor to keep it clean).

With less fuel in the tank, maybe it will gush out less quickly, so I'll probably siphon some more out and then attempt to remove the strainer and catch what comes out at that point. My intention is to re-use this strainer (from what I read on this conference, cleaning it and then reusing it is fine). I am less tempted to re-use the prefilter, but I cannot comment on that. The prefilters are cheap, though, and easy to get....