Fuel Tank Draining - PeachParts Mercedes-Benz Forum

cavaliers16 · #1 02-14-2007, 12:02 PM

With school vacation next week, I'm trying to get everything ready so that I can fix the booming algae population that is inhabiting my fuel tank. The algae has gotten so bad that the tank strainer is entirely consumed with about 1.5" of junk

. That's why I've been clogging fuel filters every 20 miles.

Anyway, I'm trying to figure out the easiest way to drain the tank. I can't unhook the fuel strainer line and drain into that because it is totally clogged (the car won't even run it is so bad). I've got four 5-gallon diesel cans to put the stuff in (darned full tank) so I need to figure out how to get it out of the tank and into the jugs. Can I drain it through the return line, or is there some sort of foot valve on the return line? I'm thinking my only hope is to siphon it out with a section of 5/8" heater hose that I had left over from another project, but then I would need to buy a siphon pump (I'm not going to risk sucking the stuff down- I've had enough diesel smell damage done from the last drain

).

Any ideas?

dmorrison · #2 02-14-2007, 12:07 PM

If you have a compressor. Blow air into the drain line. That will force the algae away from the screen and allow fuel to drain.. You may have to do this a couple of times to drain the tank. Or get a hand pump and suck it out of the filler neck.

Dave

Biodiesel300TD · #3 02-14-2007, 12:10 PM

You can drain it through the return line. Pull the rubber line of the metal line that goes up front and have a fuel can ready. You can clamp the rubber line with vise-grips or the like to stop the flow when the can is almost full, so you can get another can. Also I would properly dispose of the fuel you remove from the tank so you don't re-contaminate you tank.

Are you going to pull the tank and have it cleaned, or just put in fresh fuel and some biocide?

BTW: Your growing fungus, not algae. Algae needs light and water to survive. And you shouldn't have either in your fuel tank.

cavaliers16 · #4 02-14-2007, 12:16 PM

Quote:

Originally Posted by Biodiesel300TD

You can drain it through the return line. Pull the rubber line of the metal line that goes up front and have a fuel can ready. You can clamp the rubber line with vise-grips or the like to stop the flow when the can is almost full, so you can get another can. Also I would properly dispose of the fuel you remove from the tank so you don't re-contaminate you tank.

Are you going to pull the tank and have it cleaned, or just put in fresh fuel and some biocide?

BTW: Your growing fungus, not algae. Algae needs light and water to survive. And you shouldn't have either in your fuel tank.

OK, I have a booming fungus population. It's really ugly.

I am going to pull it and use simple green and a pressure washer to clean it. Since I have all week to do it, I am going to do it several times, letting it soak each time. I'll clean the sender while I am at it. Then when it is time to put the new fuel in I am going to pour some biocide in there to kill anything that is left.

I will definitely clean it- I made the mistake of not cleaning it last summer and the algae came back really fast.

And Dave- I do have a compressor but there is so much crap at the bottom of the tank it would clog up again in seconds. The whole bottom of the tank is just covered with fungus. This car sat for the last 8 years (owned by an old guy who never drove it) so I'm not surprised it is so bad.

Thanks for the tips!

pselaphid · #5 02-14-2007, 12:36 PM

Quote:

Originally Posted by Biodiesel300TD

BTW: Your growing fungus, not algae. Algae needs light and water to survive. And you shouldn't have either in your fuel tank.

Or more likely bacteria, though some yeasts will grow there too. Some of the same ones that help clean up tanker spills clog fuel filters. I had good luck with a moderate case using Biobar from West Marine. Took several tanks to clean it up, but seems to be gone now and for about $25 you will get enough to last a long time as a maintenance treatment.

If this doesn't bring it up, do a search in West Marine for "Biobar." I guess a number of products work, but this was locally available.

http://www.westmarine.com/webapp/wcs/stores/servlet/SiteSearchView?catalogId=10001&Ntx=mode%2Bmatchallpartial&keyword=biobar&Ntt=biobar&N=0&y=18&x=8&storeId=10001&Ntk=All_2&ddkey=SiteSearch

Ok, well it didn't post the complete link with that edit. Just go to westmarine.com

dmorrison · #6 02-14-2007, 02:14 PM

http://www.peachparts.com/Wikka/W123FuelTank

Dave

cavaliers16 · #7 02-14-2007, 02:18 PM

Quote:

Originally Posted by dmorrison

http://www.peachparts.com/Wikka/W123FuelTank

Dave

That is a great pictorial. I saw that a while back and bookmarked it for this cleaning, so as long as I can get the fuel out I am all set.

Do you think that I should get rid of all 20 gallons of diesel that are in there now? I don't want another fungus problem but I did spend close to $60 for it.

cavaliers16 · #8 02-14-2007, 02:30 PM

Quote:

Originally Posted by pselaphid

Or more likely bacteria, though some yeasts will grow there too. Some of the same ones that help clean up tanker spills clog fuel filters. I had good luck with a moderate case using Biobar from West Marine. Took several tanks to clean it up, but seems to be gone now and for about $25 you will get enough to last a long time as a maintenance treatment.

If this doesn't bring it up, do a search in West Marine for "Biobar." I guess a number of products work, but this was locally available.

http://www.westmarine.com/webapp/wcs/stores/servlet/SiteSearchView?catalogId=10001&Ntx=mode%2Bmatchallpartial&keyword=biobar&Ntt=biobar&N=0&y=18&x=8&storeId=10001&Ntk=All_2&ddkey=SiteSearch

Ok, well it didn't post the complete link with that edit. Just go to westmarine.com

The link worked for me- there's a West Marine about half an hour from here so I think I'll go over there this weekend and pick up some of that stuff. I don't want to have to fix this again. Thanks for the link.

Biodiesel300TD · #9 02-14-2007, 02:35 PM

Quote:

Originally Posted by cavaliers16

That is a great pictorial. I saw that a while back and bookmarked it for this cleaning, so as long as I can get the fuel out I am all set.

Do you think that I should get rid of all 20 gallons of diesel that are in there now? I don't want another fungus problem but I did spend close to $60 for it.

I would personally get rid of it just to be safe, that just me though. But you could probably treat it all with a biocide and it would be fine.

Sbean · #10 02-15-2007, 12:34 PM

Spelling is Biobor. Steve

Jadavis · #11 02-15-2007, 01:17 PM

Once everything is clean, try some Startron tank cleaner when you put the fresh fuel in.

I was clogging filters every 500 miles until I double dosed the tank with startron. After that I have run it at the recommended rate. Great stuff.

-Jim

cavaliers16 · #12 02-15-2007, 03:53 PM

Jim-
Where did you get that stuff? I'd like to pick some up while I'm out this weekend getting the Biobor to kill the darned fungus.

Jadavis · #13 02-15-2007, 03:55 PM

West Marine also.

http://www.westmarine.com/webapp/wcs/stores/servlet/producte/10001/-1/10001/234219/0/0/startron/All_2/mode+matchallpartial/0/0

-Jim

cavaliers16 · #14 02-15-2007, 03:56 PM

Great- I'll pick some up on Saturday.
Thanks!

jbach36 · #15 02-15-2007, 10:53 PM

I heard if you use your car as a daily driver, you don't have to worry about an algae problem. Is that true? Either way, how would you know, unless you looked inside your tank with a flashlight?

jeff 1991 300d, 101k