Cleaning Fuel Tank

Engines, Drive trains, Propellers, Steering, Ground Tackle and other mechanical system
midnightsailor
Posts: 140
Joined: Thu Aug 06, 2009 1:21 pm
Location: Greenport, New York

Cleaning Fuel Tank

Post by midnightsailor »

I have noticed my dual Racor 500 fuel filters showing quite a bit of black sediment in the bowls so I decided it was time to clean the fuel system before I have any major problems or imminent disasters while underway. I removed all the screws holding the inspection port to the fuel tank, making sure to index the cover to be certain it goes back on the same way. When I pulled the cover off, which by the way also has the fuel gauge mounted on it, I found the gauge float covered in black gunk, which I assume to be dead algae. The fuel in the tank, which was about 1/2 full also looked black. I plan on pumping out all the fuel into jerry jugs and burning it in my house furnace. I'd like to be sure that my tank, fuel lines and filters/ filtert units are clean and free of gunk and dead algae. Does anyone have any suggestions or thoughts of the best way to go about this or any things to watch out for, any useful hints, or things I might overlook? I want to do this only once and get it right.
I plan on agaitating the fuel with some kind of paddle or spatula while pumping it out of the tank into the jugs. Should I have a few gallons of clean fuel available and use it to rinse tank after /during scrubbing ytank walls with a long handled brush , perhaps disposible diapers or absorbant engine pads to wipe out tanjk sides ,bottom? Then fill atnk with clean fuel and pump it out of tank, through lines to flush them out?
What about return line, should I even be concerned about that small amount in the line? DO you think it neccesary to remove racors (a rather dauntinhg project as they are rather hard to get at and remove considering all the connections andfaasteners, or would just changing out the elements be sufficient?
What about preventing any future dead algae problems and maintaining a clean fuel tank and fuel supply....some say use Biophor some say never use it. I have been using that plus Stabile since I got the boat 3 years ago but who knows how it was maintaained previously?
The boat is a1982 Freedom 33 cat ketch with the 3gm Yanmar.
BTW, Happy Spring......look forward to Some great summer cruises.
1982 Freedom 33 Cat Ketch, Hull # 53, Standard Booms, deep keel ,tall rig
An armed man is a citizen, An unarmed man is a subject. George Washington

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GeoffSchultz
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Re: Cleaning Fuel Tank

Post by GeoffSchultz »

I would suggest that you get some StarTron Enzyme Tank Cleaner by StarBight. Use that for 2 tank fills and then switch to using their StarTron Enzyme Fuel Treatment when you refill. Emptying the tank sounds like a good start. I think that this should take care of the rest, unless you want to bring in a fuel polisher.

-- Geoff
BlueJacket
1997 Freedom 40/40
http://www.GeoffSchultz.org

midnightsailor
Posts: 140
Joined: Thu Aug 06, 2009 1:21 pm
Location: Greenport, New York

Re: Cleaning Fuel Tank

Post by midnightsailor »

I have never heard of those additives, will definately look into them. I take it you have experience with themm and have had good results.? I am pumping out old stuff and burning it at home, as matter of fact ,pumed out five gallons and its burning in my furnace as I write this. I used a clear suction hose and as I moved it around the bottom of tankk could see it go from clear red to jet black so I kept moving it as to keep the black stuff flowing up the hose. Definately a lot of crud in the tank. Puzzled as to how to get to other side of baffle, will have to do my best with the hose through the hole in the baffle.
1982 Freedom 33 Cat Ketch, Hull # 53, Standard Booms, deep keel ,tall rig
An armed man is a citizen, An unarmed man is a subject. George Washington

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GeoffSchultz
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Re: Cleaning Fuel Tank

Post by GeoffSchultz »

I use the StarTron Fuel Treatment every tank. I've run 2 tanks of the Tank Cleaner through without any changes, but I always thought that my tanks were clean. I have friends who have used the Tank Cleaner with great success. Just follow the instructions and then watch your filters as the use of this product may cause them to load up a lot faster. I have a vacuum gauge on my Raycor, so I can easily see how it's doing. Be sure to carry spare filters if you just start using this and carefully listen to your engine. You don't want to be going into a tricky location and find my engine starving for fuel because of a clogged filter.

You may find that the Tank Cleaner only comes in large quantities, so find a friend(s) who wants to clean out his tank too and split the bottle. I have enough for myself and many other boats.

-- Geoff
BlueJacket
1997 Freedom 40/40
http://www.GeoffSchultz.org

AlanK
Posts: 127
Joined: Wed Dec 10, 2008 6:59 pm
Location: Freedom 33 Boston, MA USA

Re: Cleaning Fuel Tank

Post by AlanK »

Assuming your F-33 tank is like mine (your description so far sounds the same) its easy to clean the tank itself. I do it every couple of years.
I just remove the inspection port when the tank is is low on fuel. I then use light rags or paper towel to reach in and manually clean the tank sides bottom and especially the recessed part where the feed tube is. I then pump out the rest of the fuel ( I find it easier to clean with some fuel in it but I don't let the black stuff build up much).
The only challenging part is there is a baffle and you have to slide whatever you clean with under/around this (sometimes I use a thin gripper tool)(and you don't want to use paper towel since if it rips its hard to get out. In the part that's beyond the baffle I probably don't get everything out but I do get it mostly clean and one can always agitate etc.
I've never had visible black in the racors so can't comment on that.

carhelpguy31
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Joined: Wed May 02, 2012 8:04 pm
Location: Flint Mi

Re: Cleaning Fuel Tank

Post by carhelpguy31 »

I just did this last summer on out 30/32. I had just bought the boat and the fuel and the boat had been sitting dormant for the last 8 years. The fuel was getting slimy and milky. I drained the tank (all 18 gallons of it) into cans. I then had a gallon of non aerosol brake parts cleaner from the dealership I was working at. I sprayed that all over in the tank using a small pressure sprayer used for treating weeds in my lawn. The wand was flexible enough to reach in behind the baffles. I then mopped out the brake cleaner and let dry out. Oh, and I also flushed the filler line with clean diesel during the draining process. Once the tank was cleaned out, I replace the racor and small engine filter. I then removed the return line from the tank and put it into a separate container. I started the engine, purged the air out and after seeing clean fuel from the return line, I reinstalled. I added clean fuel with a good biocide to the tank and she runs great.
Mike Russell
Bazinga!
Freedom 30/32
Cheboygan, MI.

midnightsailor
Posts: 140
Joined: Thu Aug 06, 2009 1:21 pm
Location: Greenport, New York

Re: Cleaning Fuel Tank

Post by midnightsailor »

These suggestions are great ! Thanks for your help, I hopefully will be finishing this job tomorrow. This fuel has been sitting pretty stagnant in this tank for quite a few years so there is quite a mess, just glad I got to it before I got stuck somewhere. I cleaned up the fuel float and linkage today, but could not get to the boat as I had some other pressing chores (yard work) Will ley you know how it goes, thanks
1982 Freedom 33 Cat Ketch, Hull # 53, Standard Booms, deep keel ,tall rig
An armed man is a citizen, An unarmed man is a subject. George Washington

midnightsailor
Posts: 140
Joined: Thu Aug 06, 2009 1:21 pm
Location: Greenport, New York

Re: Cleaning Fuel Tank

Post by midnightsailor »

Well, I went to local chandlery and found the starbright fuel tank cleaner and fuel treatment. Your right about there only beinga very large jug of the tank cleaner.....passed on that for now as I am short on cash but picked up the fuel treatment. I will see if I can find someone to split cost of the tank cleaner. Went to boat and finished pumping out fuel. There was so much crud arouind the pick up tube recess I am surprised that fuel even managed to be picked up. I am convinced if I had not tackeled this ,I would have been stuck somewhere this summer, probably at the worst time! I used absorbant engine pads and a scrub brush to clean out all the crud and slime from the forward half of tank. I had to resort to a small"toothbrush size" brush to clean out that pick up recess. I would have liked to pull out the pick up tube but unfortunately there is not enough clearence to rotate either or both the pickup tube and /or the cut-off valve. Either one will only rotate about 1/2 turn before hitting either the deck beam or the tank. Obviosly , the pickup and cutoff valve were already on tank when it was installed and then the deck was installed with the deck beam layed too close to the pick up tube.....consodered making a cut into beam but it would have to be to heavy a cutout, guess I will live with it and hope I never havbe to remove it.
I have the forward half of tsank clean now but I can see the back half, behind the baffles is just as cruddy. I wisll try to rig up some kind of pressure washert to insert in there like the suggested insecticide spayer. I can't believe all the sand and gravel that was in the tank. Mus get in through cockpit fuel fill and must be in deisel fuel that was used and just built up ovefr time. Amazing!!
1982 Freedom 33 Cat Ketch, Hull # 53, Standard Booms, deep keel ,tall rig
An armed man is a citizen, An unarmed man is a subject. George Washington

plolic
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Location: Vancouver, Canada

Re: Cleaning Fuel Tank

Post by plolic »

On the maiden voyage onboard (new to me) my 1986 F36/38 bought three years ago i ended up disabled (engine would not run) luckily just off Anacortes Marina on my way from Seattle to Point Roberts. It was the constant clogging of fuel filters with water and dirt. Emergency tow (20 minutes in duration) to the marina cost me $350!! Having had a SS tank with an inspection port covering entire tank on my previous boat i was feeling somewhat apprehensive having an aluminium tank under the quarter berth fixed plywood board and not knowing what was in the tank. So i cut the plywood open just little wider than the tank. figured out it will be impossible to take the tank out, I resorted to opening a 6 inch diameter round hole in the middle of tank top. Tank interior did not look good and i found baffle plates, which required cutting another two 6" diameter holes above each of the sections. After that I pumped out all of the fuel, scooped the water and grime collected. Scraped off the rest of the hard stuff. sanded/wire brushed the tank interiors as clean as i could. Fitted 1/2" inch larger diameter aluminium covers and sealed with liquid gasket maker (nota drop of diesel leak so far) . I am sure my tank is good to go for another 25 years, but in case it needs earlier attention, it will take 30 minutes to open up for inspection and cleaning.

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Rick Simonds
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Location: Tallahassee, FL

Re: Cleaning Fuel Tank

Post by Rick Simonds »

About every four or five years I let my Hoyt 32's tank get down to only a gallon or two. I pump that out and discard it, along with any water and funky gunk in the bottom of the tank. I'm fortunate that I can easily reach into mine through a clean out port and scrub it out. I just use a green plastic scrubby pad and "fuel dryer". Fuel dryer is something that is supposed to absorb the water in fuel and allow it to pass through the engine. It sure smells suspiciously like plain isopropyl alcohol. It does cut through the gunk very easily, though.

Once everything looks bright and shiney I wipe everything down with some paper towels and refill it with fresh fuel. Good for another four years or so.
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Rick
Tallahassee

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