Source of Oily Film Coating Storage Locker?

[Gone2long]

Folks

I use the outer hulls of my multihull sailboat for storage purposes. In one hull I stored five "empty" diesel fuel containers (meaning the containers had less than an ounce of fuel left in them after they were emptied and stored in the hull). The containers were emptied OUTSIDE the hull and their outsides were clean and dry when I stored them. The hull in which they were stored was also relatively clean and dry.

I also had a 2cycle generator stored there with about 2 liters of gasoline in its tank. The gas was mixed 50/1 with 2 cycle motor oil. Not smart, I know, to leave such stuff in the tank for very long.

Lastly, I also stored about a liter of kerosene in the outer hull, along with these other fuels and containers.

While cruising for a few months with said containers stored as noted above, I closed the storage hull's deck vent because it was allowing water to enter the hull in rough seas. After reaching our intermediate destination and due to other, pressing concerns, I had to leave the boat docked for about 5 months in tropical heat, and I neglected to open the vent during that time. Another less-than-wise move.

When I finally opened the hull to do a routine inspection and cleaning, I noticed a dark brown oily film over the entire area where the containers were stored. The bilge had a couple of inches of dark,oily salt water in it, which, I suppose, was to be expected, but there was also up to 1/8th inch of oily film laying on top of the ribs. And, even the underside of the deck was coated with a dark brown, oily goo.

Also odd was the fact that all the empty plastic, diesel containers had dark brown spots and drips of oil all over them, as if the oil had dripped down onto them from the underside of the deck.

I am wondering why and how all of this could have happened, but find it all rather perplexing. Could the heat in the unventilated hull have caused the small amounts of fuel in the containers to vaporize and rise to the undersides of the deck? Would the diesel vapors be lighter than air or rise with the heated air in the hull?

Or, could a similar phenomenon have occurred due to the stored kerosene leaking or due to the gas/oil mix from my generator leaking from the cap?

Or, could some kind of chemical reaction have occurred inside the hull? The hull is wood, with an epoxy coating. Could the epoxy be reacting to escaped/trapped fumes and causing some kind of oily film? The epoxy is very old and very hard, and no film is occurring anywhere else on the boat.

As would seem obvious from the above, I am clueless as to what is going on here so any help or advice would be greatly appreciated.

Best to all,

G2L

[svHyLyte]

You do not indicate where you are located, however, by your description, I suspect it's somewhere where the interiors of your amas can get pretty warm if not quite hot during the day. Given your list of stores, you have rather a lot of POL in different containers in your ama that is, by its nature, volatile. Get the containers heated up enough, which isn't too difficult, and even a "sealed" container will vent fumes. The vaporized oils will of course condense and as the ama cools after sunset and especially so on the hull and underside of the deck if the surrounding water is cool relative to the daily air temperatures such as one finds in SoCal. Repeat that cycle daily for any time period and you're in for a good mess when you finally open the hatches. The simple solution is to provide vents to the outside air that can evacuate the fumes from the ama before they have a chance to condense.

FWIW...

[Gone2long]

Originally Posted by svHyLyte

You do not indicate where you are located, however, by your description, I suspect it's somewhere where the interiors of your amas can get pretty warm if not quite hot during the day. Given your list of stores, you have rather a lot of POL in different containers in your ama that is, by its nature, volatile. Get the containers heated up enough, which isn't too difficult, and even a "sealed" container will vent fumes. The vaporized oils will of course condense and as the ama cools after sunset and especially so on the hull and underside of the deck if the surrounding water is cool relative to the daily air temperatures such as one finds in SoCal. Repeat that cycle daily for any time period and you're in for a good mess when you finally open the hatches. The simple solution is to provide vents to the outside air that can evacuate the fumes from the ama before they have a chance to condense.

FWIW...

Thanks for your input - kinda what I suspected, but I'm new at all this stuff, so it's great to hear from folks who have more experience.

As per our exact location, I don't like to advertise it so, but "tropical" should have given you a pretty good idea. To give you a better idea, lets call it "11 degrees latitude".

Pretty hot down here, so, it seems that your analysis fits the situation described.

Thanks for your help,

G2L

[Gone2long]

Will ventilate the hull tonight as suggested. However, a day after wiping up the mess, the seams of my ribs seem to continue to leak oily, brown liquid. Looks and smells like dirty diesel fuel.

The wood on the interior of the outer hulls is not epoxy coated. That being the case, could the wood get saturated with oily residue, and actually leak it for a while after being cleaned?

We have cleaned up the oil, but it seems to reappear, to a lesser degree, after 24 hours or so.

Tell me what you think of this phenomenon, and thanks again for your help.

G2L

[seabreez]

Originally Posted by Gone2long

Will ventilate the hull tonight as suggested. However, a day after wiping up the mess, the seams of my ribs seem to continue to leak oily, brown liquid. Looks and smells like dirty diesel fuel.

The wood on the interior of the outer hulls is not epoxy coated. That being the case, could the wood get saturated with oily residue, and actually leak it for a while after being cleaned?

We have cleaned up the oil, but it seems to reappear, to a lesser degree, after 24 hours or so.

Tell me what you think of this phenomenon, and thanks again for your help.

G2L

SVHyLyte called it right on... and the smell and the residue can last for a long time. You can clean it very good then chlorinate clean it and then ventilate very well and then paint the locker with a good epoxy primer and then paint it. This happened to me also. This will never happen to me again... trust me!

[Gone2long]

Thanks,


Not exciting news, but sure helps to clarify the situation. We are ventilating the space now (day2) and will continue the cleanup, while considering your painting option as well. Will update this forum as per the latest.


Appreciate your input,


G2L

[svHyLyte]

Originally Posted by Gone2long

Thanks,


Not exciting news, but sure helps to clarify the situation. We are ventilating the space now (day2) and will continue the cleanup, while considering your painting option as well. Will update this forum as per the latest.


Appreciate your input,


G2L

For what it's worth, I have found that lemon juice concentrate, which can be obtained relatively inexpensively at bulk food suppliers such as "Smart'n FInal" in SoCal and at restaurant suppliers makes an effective cleaner/deodorizer when combined in relatively high concentrations with hot soapy water. It has worked well for us on a couple of occasions when we needed to do a cleanup after a fuel and/or oil leak in the engine compartment. Getting rid of the smell of the fuel was a foremost concern and the material worked well for us.

[Gone2long]

Originally Posted by svHyLyte

For what it's worth, I have found that lemon juice concentrate, which can be obtained relatively inexpensively at bulk food suppliers such as "Smart'n FInal" in SoCal and at restaurant suppliers makes an effective cleaner/deodorizer when combined in relatively high concentrations with hot soapy water. It has worked well for us on a couple of occasions when we needed to do a cleanup after a fuel and/or oil leak in the engine compartment. Getting rid of the smell of the fuel was a foremost concern and the material worked well for us.

Thanks for the tip.

We have used vinegar solutions in similar situations, and when we needed it to mediate corrosion. Do you think that vinegar would work on the diesel stains/odors? Seems like the same active ingredient may be at work in both lemon extract and any type of vinegar.

Regards,

G2L

[zeehag]

check your engine for any oily leaking around air cleaner.
check your engine and exhaust for small leakage--tighten all hose clamps and keep ventilation open while sailing. face cowl vents aft when sailing.
99cent stores carry a cleaner named awesome. i can find in cheapo stores in mexico also--particularly wallys, not walmart, wallys. works well. superconcentrated and you mix it down as needed. spray bottle
mr musculo also cuts the grease engines use and produce. i use on dishes for food grease, clothing for body grease and towels i use on engine grease--works well.

[Suijin]

Any sort of concentrated citrus is a traditional cleaner for diesel spills or residue. Not sure why but it seems more effective than anything else at removing the odor which can linger and be difficult to vanquish.

[svHyLyte]

Originally Posted by Gone2long

Thanks for the tip.

We have used vinegar solutions in similar situations, and when we needed it to mediate corrosion. Do you think that vinegar would work on the diesel stains/odors? Seems like the same active ingredient may be at work in both lemon extract and any type of vinegar.

Regards,

G2L

I suspect that white vinegar might work but, perfectly frankly, the smell of vinegar isn't much of an improvement over the smell of diesel (at least in our humble opinion). The smell of lemons or oranges, by comparison, is quite pleasing or at least endurable to most (again IMHO!). Moreover, a gallon of lemon concentrate is no more costly, and often less costly, than a gallon of white vinegar in our experience and seems to have less of an adverse effect on metal surfaces considering a somewhat lower acidity ounce for ounce. Note, however, I am not an expert in food science nor anything vaguely related to the issue. Our/my own experience is/was based upon the suggestions of an old (i.e. very elderly) mechanic, who "knew his stuff". 'S'worked for us, maybe for you too. N'any case good luck with your clean-up and good sailing in future!

[Gone2long]

Thanks mate,


Understood.


Regards,


G2l

[Gone2long]

Thanks for your input.


Problem is in the AMAs though, and, thankfully, not in the engine compartment. : 0


Best regards,


G2L

[Gone2long]

Originally Posted by Suijin

Any sort of concentrated citrus is a traditional cleaner for diesel spills or residue. Not sure why but it seems more effective than anything else at removing the odor which can linger and be difficult to vanquish.

Thanks for your input,

G2L

[sailormed]

You can also try using washing machine fabric softener. I have not tried it yet personally but it was mentioned in several CF threads. Should be excellent for eliminating diesel fuel odors.