We had a nice event today at our small marina. We had a guy from a company that cleans fuel tanks
. He did a few and it was interesting to watch and see the results.
was really pretty slick. The whole out fit it mounted to what looks like a tall luggage cart like the FedEx guys have. On the bottom was a nice tray to catch any spills plus an electric motor
that pumps 400 gallons per hour. The hoses that go in the tank are just like you see at the corner fuel dock
. The filter itself is about 9 inches in diameter and about 16 inches tall. The filter is fitted with a precut sheet of filter paper that is rolled on the inner cylinder and held by two quick release hose clamps. Fuels is pumped from the tank to the outside of the inner cylinder and forced through the paper to the inner side and out to the tank. It looks like a very large racor
The first tank was a neighbors 2000 Bavaria
37. So it's not an old boat but it pulled out a bit of crud by the end of a few hours it was clear that the filter was nice and pink with just some thin film of gray on it. It took about 4 passes to get it clean.
The next boat was a 20 year old 35 ft Sea Sprite with a 19 gallon tank. My other neighbor only uses the engine
to get out into the river for the local races and comes back. The fuel tank
was half full and over 1 year old.
One of the features of this system is two pressure gages. One is the out bound pressure and the other the inbound. After it equalizes in a few seconds the out pressure is a bit over 30 lbs. The system is run for a period of time until the pressure drops to say 5 lbs. This boat ran the pump for about a minute and then the filter paper was changed. It was black solid with chunky bits. The next filter ran for 5 minutes before it too was changed but the color was very dark but not solid black. Filter 3 ran 20 minutes and now was gray but all the chunks were gone. Filter 4 started out at 30 lbs and held for about 20 minute then drops just a few pounds.
The last filter was gray because the dye in the fuel was pretty much dead. US fuel used off road has a red dye added at the factory so it can be sold road tax exempt.
It all points out that neither boat was really bad enough to not run but both tanks
did accumulate a lot of crap. Dead algae, emulsified water
and assorted bits of who knows what.
I have an aft tank that is very bad and it actually has almost no fuel but has sat a long time since before I got the boat. It appears the cheapest solution will be to add about 6 gallons of fuel and pump the heck out of it. the process they use is to place the hoses through the inspection ports
not the fill tubes. The supply end is moved around so it becomes like a power washer inside the tank. At 400 gallons per hour 10 to 15 gallons gets recirculated and filtered pretty fast.
In this part of the world the cost is $75.00 US per hour without travel time but includes set up time. It includes all the materials (the filters and disposal). The show isn't a whole lot to watch as the final filters don't come out real dirty but they do tend to start getting at the hardest deposits. We were getting ready to take bets on how long each new filter would last so it's worth having a case of beer
and a few friends over for the event. From what I saw a 7 year old tank showed enough deposits on the filter to make it seem worthwhile and a 20 year old tank with old fuel seemed very well worth it.
The important thing I learned is that for best results get the tank down low as it promotes more recycles through the filter paper and so catches more stuff quicker. It will save hours you don't have to pay for and you'll get a clean tank anyway. Adding new clean fuel to old fuel is better when there is less of it to dilute.
there is a company in Maine
selling the gear
to do this work as well as a smaller scale unit you can install in your boat, but I think for most sail boats having it done every 7 or so years would not be a bad idea. I had my other tank go real bad and strand me with too much algae bringing home after purchase
. It's one of those things that really is impossible to survey
unless you polish it.