Water in diesel tank

[Perfect Excuse]

Water got into my diesel tank, don't ask really dumb, I syphoned about ten gallons from the bottom of the tank thinking the I could get the water out without emptying the entire tank. Should that work or should I drain the entire tank? My problem is disposal.

Secondly, I put in new filters, but I am not sure if I got all the tainted fuel out of the lines. Does anyone have suggestions how to make sure that I got all the old fuel from the lines to the injectors?

I tried staring with starter fluid and it starts easily but quit with the starter fluid. I think that means that there is still water in the diesel. Should I bleed the injectors? Do I do that by loosening the nut or do I take the line off the injectors completely?

Tips or suggestions?

 

[Don S/V ILLusion]

It's almost impossible to separate the water/fuel mix. There is a whole technology built around oil/water separators. Even if you did manage to remove the water phase, you will still have sufficient water emulsified in the oil to cause problems down the 'road'. You might be able to manage with prudent monitoring of the primary fuel filter and constantly drain the water caught therein but it's not a comfortable feeling knowing the problem will arise at the worst time under power entering/leaving a dock or motoring around a mooring field.


Only when you are sure there is no more water in the tank or any filters, crack the injectors one at a time to monitor what comes out.

And don't use starter fluid on a diesel. That's the worst thing you can do, especially repeatedly. If you have to use anything, use WD40 sparingly.

 

[Steve Dion]

Many fire departments will accept old fuel like this. They use it for training purposes. It is worth a try, all they are going to say is NO.

I would suggest that you clean out the lines from the injectors back to the tank. You may need to do it in sections but it will be a good thing to know what you have removed all of the water from the lines before you refuel it again.

 

[Mulf]

You mean Dumb like...

..planning to take the hose and flush out the holding tank vent but putting the hose in the diesel tank vent? Don't feel bad, how do you think I know that someone could be dumb enough to do that?

 

[Perfect Excuse]

Thanks all. I note not to use starter fluid, thank you. I did manage to syphon from the bottom of the tank successfully. After that, I drained the fuel lines from the injectors back to the filters, replaced the filters, pumped up the system and finally, bled the injectors. I knew this in theory, but this was my first time in practice. And yes, it was my error when going to flush water through my aft holding tank. The fuel tank now has an "X" in tape across it which now a boat custom.

 

[RichH]

If you have a 'clear sump' in your Racor filter(s), keep a 'constant eye' on them for the immediate future for signs of visible water, then drain when necessary as needed as the emulsified and/or 'free'/visible water drops out.

If the fuel delivery lines anywhere along the entire circuit from the tank to the engine is LOWER than the inlet/exit of the Racors, be sure to BLOW OUT THE LINES as the probability that these lines will contain free water is quite high.

Change out the Racors at the end of the season and then increase the change out interval to 6 months until you are certain that ALL water is removed from the oil. Reason: although the technical 'paper' used in Racor filter is 'resinated' its not a perfect resination that seals the cellulose component of the filter material. The cellulose can/will readily absorb water which will tend to 'digest' the filter material which in turn will make the filter material less strong, swollen and vulnerable for a 'breakthrough' if the system begins to 'plug' due to high debris and high vacuum across the pleated filter material. Also change out the 'engine guard filter' at the same change out interval as the Racor(s).

As for the (non-visible) emulsified water, If you can find them (I dont have the Racor part number available at hand), change out the Racor(s) for either the 'water blocking' (hydrophobic) filter material or the 'water absorbing' (containing a 'starch' - hydroxymethylcellulose) filter material and 'run' these for the next 6 months -- dont use the 'gasoline' versions, only those 'starch-filled' versions that are compatible with diesel fuel.
Upon thermal changes in the fuel, non-visible emulsified water 'can' change to 'free water' and if the free water does get through the sump of the Racor(s) it can damage the tips of the HOT fuel injectors.

If you have an 'oil burner' at home, best is to entirely drain the fuel tank, take the oil home let the free water 'settle out by gravity' (remove it by siphon) and use the water emulsion saturated oil in your home oil burner (a few gallons at a time). The pump on the home oil burner will 'chop up' the free water into an emulsion.


Be sure to 'shock dose' the fuel tank with a 'bacteriostat' such a BioBor, to lessen the potential of a rampant fungus/bacterial growth.

 

[Perfect Excuse]

Thanks Rich. Great explanation. Helps to understand the reasons behind the procedure rather than simply doing maintenance by rote. Bob