Fuel Contamination

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If it reaches your injector pump it WILL fail. Check that it actually is water?
 
If you really want to polish your fuel you need a BIG pump, not one of those tiny rattlers, very useful for bleeding lines but pointless for a polishing system. If you ever take the top off your fuel tanks, there will be a layer of asphaltenes on the bottom and stuck to the walls, you need a serious pump to blast that crud out and get it through large filters. Hire someone to do it right and get inspection plates installed in your tanks while you’re at it. Unless you have not solved the leak, you will only have to do this once.

Those tiny pumps for cleaning fuel are a waste of time.
 
My suspicion is that the purpose of the slot in the neck was to create a vented cap. The slot ends well above the deck, so it would take a bit of standing water to get in via the slot. Certainly makes the gasket superfluous if nothing else!
 
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The tank already has a vent. It would be superfluous and just a place for water to get in. Makes no sense to me.
 
If you really want to polish your fuel you need a BIG pump, not one of those tiny rattlers, very useful for bleeding lines but pointless for a polishing system. If you ever take the top off your fuel tanks, there will be a layer of asphaltenes on the bottom and stuck to the walls, you need a serious pump to blast that crud out and get it through large filters. Hire someone to do it right and get inspection plates installed in your tanks while you’re at it. Unless you have not solved the leak, you will only have to do this once.

Those tiny pumps for cleaning fuel are a waste of time.

I'd agree that a larger capacity pump is needed for fuel polishing, smaller pumps offer what I call supplemental filtration, still valuable but not polishing. However, regardless of the pump capacity it will not clean the tank, it may remove some material but having cleaned many tanks in my career I can attest to the need for pressure washing or mechanical scraping. Polishing systems can clean fuel and remove water (and thereby keep a tank clean), they cannot clean a tank that is contaminated with years of asphaltene, crud, biological fallout etc.

I have found the most effective way to clean a contaminated tank is first by accessing every baffled chamber, and second using a hot water pressure washer. Alternatively, you can scrape, scoop or scrub the inside but that is labor intensive and not as complete. Never use oil absorbent pads to wipe the interior of a fuel tan, they will shed threads that will eventually clog the pick up or tandem Racor valve.
 
My only goal with this extraction set-up is to remove as much water as possible from the tanks. The Kolor Kut paste indicates about 1/2-1” of water on the bottom. The crud show is just causing me to use more filters. I have no expectation of cleaning crud from the bottom of the tanks. I’d prefer not to disturb it at all. The tanks are 41 year old original aluminum tanks and replacement is just a matter of time.
Cheers!
Steve
 
Undyed fuel and dyed fuel when mixed just become a slightly less red dyed fuel. So the clear stuff in the sight glass can't be undyed fuel. If in doubt, take a sample of the clear stuff, put in a Mason jar, add several drops of regular household food coloring and shake. If the clear stuff takes on the color of the food coloring, it is water, if it doesn't, it is something else.


On your existing problem, immediately add a supply of biocide to the fuel tanks to nip any algae growth in the bud. If it was me, I would:

- Add algaecide/biocide
- Change the seal/O-ring on the filler
- Use the boat, monitoring the sight bowls and draining as necessary, and see if the quantity of "water" decreases or stops.



There are also products for use in Diesel fuel that act like the "Gas Dryer" sold for gasoline. They combine with SMALL amounts of water and allow it to pass through the engine and burn as the fuel would. I would NOT use any products designed gasoline however.


Good luck and keep us appraised of your progress!
 
My only goal with this extraction set-up is to remove as much water as possible from the tanks. The Kolor Kut paste indicates about 1/2-1” of water on the bottom. The crud show is just causing me to use more filters. I have no expectation of cleaning crud from the bottom of the tanks. I’d prefer not to disturb it at all. The tanks are 41 year old original aluminum tanks and replacement is just a matter of time.
Cheers!
Steve

You'll get SOME of the water with that but very little of the bacterial growth. That's why it's best to have a pro come in to professionally polish your fuel and scrub your tank(s).

I had to have mine done several years ago following a water intrusion event with a failed fuel cap. I pulled 4 gallons out of one tank to get home, then hired the pros. It cost $$ (mine was about $1K) to cut and install two SeaBuilt inspection plates and polish/scrub two 120 gal fuel tanks at less than half fuel but it was worth every penny.

Don't think your problems are all over when you can't get any more water out of the tank. My experience tells me that the problem will continue to grow and fester over time.
 
Undyed fuel and dyed fuel when mixed just become a slightly less red dyed fuel. So the clear stuff in the sight glass can't be undyed fuel. If in doubt, take a sample of the clear stuff, put in a Mason jar, add several drops of regular household food coloring and shake. If the clear stuff takes on the color of the food coloring, it is water, if it doesn't, it is something else.


On your existing problem, immediately add a supply of biocide to the fuel tanks to nip any algae growth in the bud. If it was me, I would:

- Add algaecide/biocide
- Change the seal/O-ring on the filler
- Use the boat, monitoring the sight bowls and draining as necessary, and see if the quantity of "water" decreases or stops.



There are also products for use in Diesel fuel that act like the "Gas Dryer" sold for gasoline. They combine with SMALL amounts of water and allow it to pass through the engine and burn as the fuel would. I would NOT use any products designed gasoline however.


Good luck and keep us appraised of your progress!


Not a good idea to add alcohol products to diesel to pass water through the fuel system.
Modern multi stage filtration is very effective at separating water from fuel, and is much more cost effective than f-ing up your motor by running water through it.
 
Not a good idea to add alcohol products to diesel to pass water through the fuel system.
Modern multi stage filtration is very effective at separating water from fuel, and is much more cost effective than f-ing up your motor by running water through it.

Agreed, we spend good money on water seperating fuel filters, attempting to defeat that technology by encouraging water to mix with fuel makes little sense. Racor water separators, along with Aquabloc elements will capture water (until they are overwhelmed). The other issue with emulsifiers is you have no way of knowing how much water is present, and thus no way of knowing how much emulsifier to add. My recommendation is to avoid them.

You'd do better to invest in a drain or stripper tube to remove water rather than using emulsifiers or biocides to treat it (the biological growth inside fuel tanks is typically bacteria-based not algae, algae is a plant and requires sunlight for photosynthesis).
 
Not a good idea to add alcohol products to diesel to pass water through the fuel system.
Modern multi stage filtration is very effective at separating water from fuel, and is much more cost effective than f-ing up your motor by running water through it.


Hence the reason I specifically stated that I did not recommend using any products in a diesel engine that were designed for gasoline engines!
 
There are diesel additives that emulsify water, again demulsifiers are preferred, especially where tanks can be drained of water.
 

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