Shelf Life of Diesel Fuel

[speedoo]

Nick, that looks like a great polishing system. I'm going to consider installing it with my new fuel tanks.

Thanks!

[sundown]

Thanks everyone for the suggestions of how to fix the fuel problem: There doesn't appear to be a working fuel polisher within 100 kms of where I live either for rent or for hire. I am seriously thinking about building one and renting the darn thing out!

Dealing with the actual fuel should be manageable but I am not too sure what to flush the tanks with? I will do a 'search' and see what I can come up with - I have put biocide in the tanks (closing the barn after the horse has run out). I am sure that there will be a bunch of sludge to deal with. Ah well - monkey wrenching is half the fun of owning a boat.

[zeehag]

even placing the fuel into a jerry jug and pouring it thru coffee filters will work---go figger----so why pay the 300+ for polishing whenye can make your own--even a temporary one??!!!!~~~~~~~_/)~~~~~~~~

[aboutgone]

Napa auto parts store carries a funnel with a membrane in it that wont let water pass through it......has worked for me before and only cost 20$

[s/v Beth]

I have seen filters made out of toilet paper, and west marine carries some kind of filter for bad diesel. I guess an inventive mind can overcome lack of funds, once the problem has been identified.

[Pblais]

Diesel can collect an assortment of dirt that can be filtered but it's not actually "Bad". Really bad fuel can't be filtered, most fuel can be filtered.

The commercial systems use a 400 gph pump connected to two fuel hoses like you see at a filling station. They use a large stainless cylinder with a tight lid. Inside they use a fine screen filter cartridge covered by a filter paper filter that comes in sheets. Fuel pumped to the out side is pushed through the filter paper backed up by the screen and flows out the center. The in bound line has a pressure gage so you know when the paper filter is clogged up. Filters are changed as the pressure gets high and the process repeated. The nice units are built into a hand truck so it can be transported to any dock with AC power.

The hitch to all this is the return hose has a fair amount of pressure and can be used to power wash the inside of the tank using the return fuel. This works quite well so long as you can get inside all the baffles of the tank.

The process works best if you have less fuel in the tank. Nick suggests 5 trips around and that would be true if the tank was clean and just the fuel was dirty. It's equal to what the pros find it takes to typically clean the fuel. 30 microns is fine for a cleaning process.

If the sludge is built up in the tanks hidden baffles there is no telling how long it would take. For a home made system a fuel pump is not going to magically suck it loose or you would have already picked it up in your own standard racor filtration. If the tank is really dirty using racor filters could cost a fair amount of money. I've seen tanks professionally cleaned as above use five or six large filter sheets coming out black over a period of about 6 hours. These were fuel systems that actually still worked but needed cleaning. One sheet holds several racor filters worth of crap. That would take a very long time and a lot of racors doing it the slow way.

Polishing systems don't clean dirty tanks. They do maintain fuel over time and are standard equipment on US military ships and many commercial ships. They run them 24 x 7 at sea or in port. It's a big deal when you carry 50,000 gallons and want high readiness.

Even if you don't build a polishing system, Nick's drawings and pictures do give a great example of how to construct a fuel system. Everyone needs some of the parts even for a basic system. The details of contsruction and materials are all done first rate. The drawings and documentation is all very instructive and worthwhile.

I would urge everyone to make a drawing of their system. Indicate all fittings and connections. Use it as a check list for inspection on a regular basis. Tag and identify all the parts and check for secure attachment of all connections, filters, and lines.

[captmick39]

(Seemingly like always here...man I do like that) Nothing but gr8 replies!)
Fireman had a legit. concern, however biocide CAN be replaced by gasoline (ideally ethanol free) and it's a lot cheaper than biocide. It Also WORKS BETTER than biocide, in that most of them don't fix the Original Poster's(OP's) problem AFTER the Fact, when You have the BUGS in the system. Gas WILL Kill the bugs.

Polishing is done AFTER You put the gasoline in to the diesel (at a factor of 5%. eg:50 gallon tank, full...pump out 3 gal. of diesel, add 2.5 gallons 87 octane. Leave it alone for a day.

Come back, hit the seperator & get all the water off the bottom...Your sight glass lets You see the h20; pump out the tank in to jerry cans using a strainer on the outlet side of the pump (beit hand or electric operated, avoiding sparks...drills MAKE SPARKS) covered with a coffee filter. The crap making it thru Your pump & getting caught in that strainer/filter will be enlightening. This is all ideally done from the INSIDE of the boat, from the BOTTOM of the tank via the pickup line and Aft of Your primary strainer & either aft or forward of Your water seperator.

Once You have ALL the fuel out of the tank, take another coffee filter & put it over the outlet nozzle on the jerry jug, securing tightly with twist ties(don't use zip/wire ties here unless You have the "removable" type), and begin refilling the tank with the jerry jug(s) stopping often to check the filter to make sure it's not clogged; when it is, carefully remove, replace & continue filling. It's a long, drawn out process, however it also costs about the price of a pack of coffee machine filters, for in a pinch if You didn't have enough jerry jugs, Your friends who own diesels...probably do & wouldn't mind loaning them to You for a "day".

There's no need to discard "bad" diesel, as it isn't. We used this trick, plus mixing in some (less than 15% based on the room in the tank) fresh fuel AND "Cetane" Booster on 8.5 year old fuel on a boat that had been on the hard (even though I thought the best shot simply taking it home to add to the parts washer..& I was wrong...afterward that perkins burned every ounce w/o the first hiccup)

Once You've completed the entire process, reconnect the supply line AFTER you Change any/ALL racor/other in-line filters & buy 2 of each while at the store. After the tank is exhausted, or been refilled from half down ideally at least twice, go in and swap those filters again. Problem solved...most likely, for ever. Getting the trash out of the tank (including dead algae) was the goal...recycling the fuel back to a serviceable safe & reliable condition was the benefit.

Use these tactics (minus the gasoline...we use lye instead to seperate gylcerin) for making biodiesel, & the straining process (to clean Straight WVO) is exactly the same. Settling of particulates we look forward to on the environmentally friendly "oil" side of this, however on sail/power boats, YOU don't...for that "trash" will get stirred up again soon as the boat gets back to the old "roll, pitch & yaw". DEAD ALGAE will BE "Particulates". Washing the tank is easy w/just a few gal. remaining if You have access directly above...not so easy if deck fill is via the rail; either way filling half way again, down the road & repeating the process in a few months cuts filter replacement costs to nil.

It's almost impossible to have "dead" diesel. Cleaning(/"Polishing") is is far more practical than the costs for disposal, both environmentally & financially.
Our "keeper" boat is set up with 2 sight bowl/water seperators in a row, & 2 racors behind that before the fuel pump. Never had a problem.
Military skid mounted diesel gennie has THREE Racors/Paper filters stacked in a row...point is an "extra" in-line filter (shy of it being clogged, which vs. injector pump is a GOOD Thing) never hurt & has saved many of us much grief. If You don't have it, consider adding it.
HTH,
-Mick

[zeehag]

Originally Posted by Amethyst Deonn

For heating or For running your diesel engine equipment. If you purchase bulk quantities of diesel fuel, make sure you are going to use it within that 2 year period. Diesel fuel can be affected by bacteria, and is affected by direct sunlight.

is why one adds biocide to it and why the tanks are not in sunlight--diesel fuel in a boat tank properly treated is usable for long periods of time--mine has so far lasted five years and is still good......

[Highlander40]

A lot of talk here about algae. Thats only one side of the story. Algae grows at the water/fuel interface. Keep the fuel dry and -no algae.
Parker , the maker of Racor filter units has a new gizmo. A solid state low power pump that slowly moves fuel through the Racors slowly and will collect water as is precipitates out of the fuel as it cools. This is a daily event, the fuel will hold more moisture when warm and it drops out at night. We are talking small amounts that add up over time. The pump uses so little power that it can run all the time. Check out the Parker site.

The second part of the story is the fuel side and it's stability. Diesel will form varnish and stuff called asphaltenes (thats the black stuff that everyone thinks is algae). The stuff is like road tar. The solution is to use an additive that improves solvency, like PRI-D, Algae-X, West store-n-start and others. Thats why gasoline helps, its a good solvent but you wont catch me using it. A cetane improver may help too.

To sum up this mess, If you can keep the fuel dry- biocide is not needed.
For long term storage a solvency improver will keep the gunk from forming.

Does anybody have experience with the Parker pump? I have not used it but did E-mail a guy at Parker for more info. It looks good to me but my fuel turnover is high enough to keep everything fresh.

Carl

[Therapy]

I must be missing something here.

I have been reading about this stuff for years and I just don't understand.

Why don't fuel tanks just have a low end or sump with another capped tube? Then every six months or a year or whatever, you simply suck out what is in the low end/sump and filter it or toss it?

I don't get it.

[GordMay]

Originally Posted by Highlander40

... Parker , the maker of Racor filter units has a new gizmo. A solid state low power pump that slowly moves fuel through the Racors slowly and will collect water as is precipitates out of the fuel as it cools. This is a daily event, the fuel will hold more moisture when warm and it drops out at night. We are talking small amounts that add up over time. The pump uses so little power that it can run all the time. Check out the Parker site...
Carl

Is this it?

RACOR Fuel Filtration - Filter Pumps
The Turbine Series Electric Primer Pump Kits can be retrofitted to many of the Racor 900FH or 1000FH Series fuel filters already in service. The Filter Pump is an innovative and proprietary system consisting of a pre-screen filter, a flow bypass circuit and a roller cell pump powered by a DC motor. When the switch is activated the fuel is drawn into the pre-screen and then is pumped through the housing, refilling the unit with fuel. When not in use the Filter Pump system is bypassed and the Racor fuel filter water separator functions normally. The use of this primer pump kit allows the operator to easily re-prime a Racor Filter/Separator directly from the fuel storage tank with no mess ...

➥ Parker - 760R30 FILTERPUMP (12 VOLT)

➥ Parker - 760R30 FILTERPUMP (12 VOLT)

➥ http://www.parker.com/literature/Rac...700_Series.pdf

[boatpoker]

Scientific fact: Algae does not grow in your tanks. Certain types of bacteria grow at the interface of water at the bottom of your tank and the diesel but not algae.

Best way to keep your tanks clean and fuel in good condition is to actually use your boat. For summers here in Lake Ontario I keep only my day tank (80g) full and turn it over 7-8 times a season. When we run south we turn over all our fuel about every three weeks..... I once picked up a bad load of fuel that used a lot of filters but other than that I never had a fuel problem in 20,000 hours.

If adding a percentage of gasoline to your diesel make sure it does not contain ethanol as that stuff will absorb water and inhibit the blending of the gas and diesel causing a whole new set of problems.

[s/v Jedi]

Originally Posted by Therapy

I must be missing something here.

I have been reading about this stuff for years and I just don't understand.

Why don't fuel tanks just have a low end or sump with another capped tube? Then every six months or a year or whatever, you simply suck out what is in the low end/sump and filter it or toss it?

I don't get it.

Exactly and that why we have that sump (every good tank should have one) and we have a drain under it instead of s pipe from the top down into the sump. This is where all the water ends up.

About asphaltenes: instead of diesel add-on products, you can circulate it on a regular basis (part of polishing) which takes care of it.

The only additive we use is the enzyme based bacteria control (Startron). We keep diesel for up to three years without any trouble.

cheers,
Nick.

[GordMay]

FUEL STORAGE INFORMATION:

BP on Diesel ➥ http://www.bp.com/liveassets/bp_inte...age_diesel.pdf

SAE on Diesel ➥ Long-Term Storage Stability of Diesel Fuels Effect of Aging on Injector Fouling-Stabilization By Additives Or Hydrotreating

Chevron on Diesel ➥ http://www.chevron.com/products/ourf...ech_Review.pdf

Chevron on Gasoline ➥ Technical Bulletin: Longer-Term Storage of Gasoline: Recommended Storage Practices

[Tellie]

Originally Posted by Therapy

I must be missing something here.

I have been reading about this stuff for years and I just don't understand.

Why don't fuel tanks just have a low end or sump with another capped tube? Then every six months or a year or whatever, you simply suck out what is in the low end/sump and filter it or toss it?

I don't get it.

I aways thought that would sure solve a lot of issues as well. I don't remember where or by whom, but I was once told that there is some regulation against having a sump drain or line at the bottom of a marine fuel tank. I suppose it has to do with fuel spillage if that point fails. Perhaps better minds here will know.