What to do about old fuel?

[skindr1999]

due to lack of use my fuel is now 6 mos. old and is starting to clog my fuelseps even. I run the engines weekly for an hour but that doesn't seem to be enough. My mechanic says to just run it through the filters (I have 2 racors and 1 alyska filter per engine) and change them often. Should I pay someone to suck the tanks dry (i have about 850 gallons) and refuel or keep running the engines and change filters? Anyone have experience?>:

[Soffer]

just because the filters are rapidly clogging. See if there are fuel reconditioners in your area. These folks will come out to your boat, run the fuel through a series of killer filters & water seperators and return it to your tanks clean. Far better than just disposing of it as "waste oil". I've not done it but I hear it works well.

[Genesis]

Assuming you have a good filtration system, go out for a nice run or three and burn it all. Do not refill until you are nearly bone-dry.

NOTE THAT THIS IS NOT A GOOD IDEA IF YOUR FILTRATION SYSTEM BITES!

But assuming you have a good system (e.g. Racor primaries, and the on-engine secondary), and you can keep ahead of filters clogging, do it this way.

Either that or call one of the "polishing" services.

[jim rosenthal]

with fuel filtering services. They seem to be pretty uneven; I had a bad experience with Kleen Fuels here in MD, I also used QLube, I think they were okay.

[spartonboat1]

A very solid mechanic I trust, not infrequently gets calls to run out and polish the diesel fuel of boat's that have been a long time idle. He brings a rig to boat and runs the fuel off or cycles it in and out, until the contaminents or bad fuel components are removed.

All I know...

[PascalG]

if you anticipate the lack of use to go on in the future, you may be better off investing in an onboard fuel polishing system. it's not cheap, but in the long run it might be a good investment if you don't use the boat enough.

it's really just a fuel pump, filter with pick up and returns..

do the math: your own system Vs 2 or 3 prof. polishing session... might be better...

[34Hatt]

Well this is always a problem showing up on this board and there is a easy answer. Go to WWW.AJX.US this additive does it all it has been made for the military for almost 20 years. It has a smart microbe that eats up microbial growth and a cetane boost, upper end lube, stabilizer ++++ it really does it all. I used it last year and it reduced the soot on transom 75%, gained 1kt top end and at cruise, reduced fuel consumption 10-12% and they started up so fast that even the wife made a comment, it was that noticeable. That was a bonus I never planned on, I used it cause a friend recommended it to reduce the soot. I also what too say my motors always ran pretty clean there is no visual smoke when they are warmed up but with a pure white transom after a couple hrs of running it would get dirty. I would definitely use the tank cleaning system first then use the maintenance product. I used the maintenance first cause I got it from my friend. I was using the boat and had a beam sea as it was eating the slug in the bottom of the tank and with the rocking it loosened up pieces that clogged one pickup tube. After 2 weeks the Maintenance product was done cleaning and there was no more problem. The tank cleaner will clean the tank in 3 days instead of 2 weeks cause it has more micro organisms. I also should say that I added the Fuel-Docs from AJX at the same time, which are magnets that clamp around your fuel hose in front of the filter took minutes to install and no leaks to worry about and they also help with the soot same as Algae X which can clog up from rust particles that is in the fuel from old tanks.

[Genesis]

These guys are pretty damn proud of what they're selling.

For $47 a QUART I want to know what's in there.

[Traveler 45C]

Hi guys,
So what is the best way to go?
1. Keep the tanks full to keep condensation out?
or 2. Keep enough fuel on board for the day plus a little more so the fuel doesn't get old?
Detroit says #1 & the dock pros say #2.
3. Will using Pri-D with the tanks full keep the fuel stabilize enough to last more than 6 months?
So many options, so many questions... Thanks all for your knowledge & wisdom,
G

[Genesis]

Quick turn over is more important (by far) than attempting to eliminate condensation.

There is next to none of that going on. Really.

If you have water in the fuel, its coming in the deck fills or worse, in the vents (worse because if its coming in there its probably SALT water!)

Fix the real problem and don't keep fuel on board you cannot burn within a month or two.

[eze2bme]

Hey 34Hatt ... where did you find that AJX additive? I called their number from the website and got an answering machine. Thanks. (I'm in South Carolina.) I haven't had any problems with bad fuel (knock on wood!) but this looks like it might be a good preventative.

Has anyone else had any experience with this additive? Sounds almost too good to be true even at $50 per qt.!

[Genesis]

... Better ask that question.

BTW, emulsifying water is NOT the right approach. Go ask a diesel mechanic what water does to injector plungers. Cover your ears if you don't like foul language.

There is exactly one approach that is correct to water in your fuel tank. Get it out of there. Not burn it, remove it. You do NOT want to emulsify it and let it pass through your injectors, scoring the hell out of the plungers. You want to suck it out wholesale.

I am extremely leery of claims like that made on this company's web page. If they want me to run a "snake oil" test on it like I did the Algae-X devices, I'd be happy to - I have some NASTY old fuel laying around in a jerry can, and if it cleans up ok with theri "magic elixer" I'll even pay to have it analyzed and see how good it really is, by objective measurement, once their "stuff" is done with it.

I don't want pictures - I want fuel analysis results.

[PascalG]

here is an intersting piece on condensation:

www.yachtsurvey.com/myth_..._tanks.htm (http://www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm)

I'm also very sceptical about all these miracle additives... when a deal is too good to be true... it is... although @ $50 a can.. is it that good?

[34Hatt]

First off Just try that # again someone is usually there during normal hrs. I should also add that I always used a additive prior which was amsoil diesel modifier which never showed any change. I know off 5 people personally that use it and have had great results I would have never recommended it if I did not use it first. And for what we spend on boats I can't believe the focus on the price. Try putting in a biocide, cetane booster, stabilizer, Injector cleaner and upper end lube and see how much it will cost. Plus READ my last post 10-12% fuel reduction and also gain a kt of speed so the quart does 500 gals of treatment so in most cases do the math and you will save money and that going to be real easy this Summer. As for snake oil I figured if the government has been using if for 20 years it really isn't magic. If you really need more Info talk to Archie at AJX. I do know that the MSDS says trade secret on it. But he will tell you how it works and he owned a fuel polishing business in FL for many years so he has seen it all and knows about fuel. Also the friend that started me on it got bad fuel in the Bahamas set of filter was lasting 4 hrs used the product made 5 trips between NY and FL plus going back to the Bahamas twice finally changed filters this fall even though vacuum gauges still read low so I would guess last saved him a bit of $$$$ also. Like I said it worked for me and I started using the gas additive in my truck this winter I run 87 instead of 89 octane and gained 12-15% A quart saves me a min of 40$ a bottle and truck runs better.

[Genesis]

Again, there are a thousand "fuel improver" formulas out there.

I want to know what's in it, and if they claim trade secret, its not going in my engine.

I do NOT want any water in the tank emulsified. No way, no how. That's bad for injectors.

I also do NOT want any halogenated compounds in my fuel. Those are also bad for injectors (and everything else in the system, from seals on down to METALS.)

Run it if you want. Its not going in my tank unless I know what's in it.

I use a cetane index improver in my Jetta and in my boat, because that does help, and I know what's in it.

10-12% fuel burn reduction? I'd have to see that on a dyno.

[SKAMMTOO]

I'll bite. I ordered a quart of the tank cleaner and a quart of the maintenance product. I have a 1965 50'MY that has one fairly good tank and one that needs attention. I pumped the "bad" tank down this winter and got out as much of the water and sludge as I could.

We'll see how this product works and I'll post here.

K:rolleyes

[SKAMMTOO]

I received the AJX tank cleaner and maintenance additives today. It'll be a few weeks before I'm really out and running, but I'll post the results as I see them.

K

[Soffer]

I know this is an old post, but what was the result of you fuel additive test?

[dmohring]

Genesis: What was the date you did the post on Algae-X testing?

[Genesis]

... there is also a new post at www.denninger.net/snake-oil-2.htm (http://www.denninger.net/snake-oil-2.htm) for tests on a relative of the Algae-X units (Diesel Tex's devices)

That test is still in process; Ivan got in the way of it to some degree, but its still going on and will be until I come to conclusions on them.

[CapetaniosG]

It is a myth that fuel tanks that are less than full promote condensation and thus fauling the fuel with water. If you do the math threre is not enough air even in a 1,000 gal. empty tank to produce more than an ounce of water. For further details go to David Pascoe's
web page and read the article.

[SKAMMTOO]

The AJX additive seemed to have work very well. I always had one "bad" tank and that has not been the case this year. I did take a little water out of the tank, but not much, and the filters are getting noticably cleaner as time goes on.

I think it was worth the 50 bucks.

K

[67hat34c]

I also am trying AJX for gas.

We found our Racor's full of a clear jelly like substance. Possibly some type of bacteria.

Added AJX but due to hurricanes we have not had a chance to realy try it out.

Will post results after we use it for a while.