diesel additive

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Takeitesea

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:) having a great summer! However, we are not traveling as much as we thought. I filled my fuel tank before winter storage and have used only half of the tank so far. Should I add any additives to protect the fuel or am I ok for the rest of the season? I will use the rest of the tank this season.
Thanks,
Don:
 
Use it enough so that you need to add some more; that way you've got new fuel coming into the mix as you go along. I usually add some Startron on my fill ups; seems to work well for us. Lots of mixed opinions on additives, as well as some very interesting reports/articles out there.
 
I installed a fuel polishing system which has worked really well. I have dual racors on each engine and can see fuel in bowls - truly cleaner. Runs two hours per day and I switch tanks manually about once a week. Here is the one I have.

Reverso Fuel Polishing Systems, Diesel Filtration, Transfer Pumps ...
reversopumps.com/
Reverso is a leader in Fuel Polishing Systems, Diesel Filtration, Transfer Pumps, Oil Change Systems. Maintain and protect your engine and generators with ...

Haven't used an additive since. 325 gallons per tank, two tanks.
 
I've heard some logic in favor of keeping your tanks as full as possible, the theory being you thus reduce the size of the voids in your tanks, which in turn reduces condensation, water contamination, and microbial growth along the fuel-water interface near the bottom of the tank. Besides following this practice, I've also had success with Biobor JF additive, a fuel microbiocide. Good luck to you sir.
 
The most common issue with marine environments bacterial and fungal growth in Diesel fuel, which will clog your filters and damage the fuel. Biocides are available and would be the only additive I would consider for Diesel fuel in a marine environment.
 
On the advice of friends and acquaintences in the marine diesel manufacturing industry, we have always used two additives in our fuel. One is Biobor JF from Hammonds, which is a bug killer. THe other was a Hammonds lubricity additive which they have since replaced with a newer product called Lubribor, which is what we use today.

The subject of fuel additives is always a good way to start a hot debate, but we decided to follow the reccommendations from people in the diesel engine business and leave it at that.

We have no idea if the additives are actually doing anything. But after 16 years of running this boat the 41-year-old engines don't smoke any more at startup than they did when we bought the boat, they don't smoke at all after startup, and the fuel filters still look as clean when they come out as they did when they went in other than being dyed red from the fuel.

Our fuel system (installed by the previous owner to replace the original system) is gravity-operated: all tanks feed from their lowest points so nothing remains in a tank when it's empty. The only pumps in the system are the mechanical lift pumps on the engines.

I have never seen any water in the filter bowls even though our fuel management process has one or the other pairs of saddle tanks empty almost all the time unless we are going on a longer cruise. (We alternate the empty tanks because they're stainless, which is a whole other subject.)

I know condensation can happen because we always got water out of the tank drains before the first flight of the day in the airplanes I flew in Hawaii, even though the tanks had been drained of water the day before. But for whatever reason, condenation does not seem to be an issue here. No boaters we know have every mentioned encountering it, and none of these boaters keep their fuel tanks full, even when they are not going to be using their boats for awhile.
 
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We use Diesel Guard which is the additive in Valvtech anytime we have a question or doubt as to the quality of fuel we might have received. We don't use it on fuels which already contain it or similar.
 
My tanks are over 37 year old steel. Use about half of the fuel load in an average boating season. I've never put anything in them other than #2 diesel. Pulled the tanks once about 15 years ago for cleaning and they had a small amount of sludge in the bottom, but nothing to worry about. If you live in a warm water climate, then you may want to use a Biocide.

Fuel polishing is a better option than pouring snake oil in your tanks. In cool water climates, keep the tanks full and don't add anything to the fuel. It's not necessary and a waste of your money.
 
Marin said:
On the advice of friends and acquaintences in the marine diesel manufacturing industry, we have always used two additives in our fuel. ......... THe other was a Hammonds lubricity additive .........
Click to expand...

A big X2 on the lubricity additive, especially if you are running a newer common rail engine with a high pressure fuel pump. The enviro-activists have forced oil companies to remove so much of the sulfur from US diesel that it barely has more lubricity now than gasoline. There is a growing trend of HPFP failures (mostly the Bosch CP4) on recent model diesel trucks/cars that have been shown to be related to the poor SCAR rating of present #2 diesel available in the US. When the HPFP grenades on a truck engine, its north of $10k to replace pump, flush lines, tanks, and rebuild/replace injectors, etc.

I've been adding Stanadyne in my truck/boat/equipment/generator fuel since I became aware of this issue. If memory serves, independent testing showed that Stanadyne improved the SCAR rating better than most additives other than running high levels of biodiesel.
FWIW....
 
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WOW, that is some pricey stuff. The GO2
 
Marin,
100% correct advice on fuel.
I also have stainless tanks and drain any water when doing the monthly engine room gearbox/battery/general check, thousands of sea miles, never changed a filter at sea or broke down.
Then again it could be down to the luck of the Irish !
 
I used additives in my GMC diesel because the pump, made by Stanadyne, needs sulfur for lubrication. I tried everything, even bought Stanadynes brand by the case. All I can say about that product is it's a pretty good cetane boost and at that not the best but the IP's failed in less than 8,000 miles, sometimes 6,000. I think it sucks as a lubricant.

All the real unbiased testing I have found shows plant oils lubricate best especially castor bean oil. Here in the US finding that is almost impossible. All the additive makers insist on fossil oil refinements that I have seen. This means bio diesel added in is the best solution and even as low as 2% plant based diesel will lubricate.

Biobor is all I use. The new ULSD is fine. I'm going over six years with no additive in my GMC and the same IP. Save your money on the snake oil.
 
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Capthead said:
WOW, that is some pricey stuff. The GO2
Click to expand...

15.5 cents per gallon of diesel. Now the manufacturer's standpoint would be that by reducing consumption by 10% it saves you effectively 40 cents per gallon for a net reduction of 25 cents per gallon even considering the product cost. I don't know if that works out in reality or not.

Bill, has it reduced consumption in your experience?

We recently have been following Dauntless and some were concerned about them having a single engine and no wing. However, even though we do have twins we still haven't ever seen that as the major concern. They are far more likely to have fuel problems than to have an engine fail. So, for those of us who do venture out a bit, anything that reduces our possibility of fuel problems is worth considering. We do have fuel polishers. Guess while some might obsess or have a little paranoia about collisions at sea and others about pirates, I would be more likely to be paranoid regarding fuel.

Part of mine comes from years on the lake and all the boats I saw get "bad" fuel. Typically it was the marina that did virtually no winter business where they filled up. There were just certain marinas on the lake not to be trusted during winter. I knew several people and obviously there were others I wasn't aware of to have problems at one marina. I basically told him either to shut down and fix the problem or I'd make sure the information was taken public. I even had him check his tank with me there. The water was three times as deep in the bottom as the maximum acceptable level so well above the pick up.
 
Marin said:
We have no idea if the additives are actually doing anything. But after 16 years of running this boat the 41-year-old engines don't smoke any more at startup than they did when we bought the boat, they don't smoke at all after startup, and the fuel filters still look as clean when they come out as they did when they went in other than being dyed red from the fuel.

Our fuel system (installed by the previous owner to replace the original system) is gravity-operated: all tanks feed from their lowest points so nothing remains in a tank when it's empty. The only pumps in the system are the mechanical lift pumps on the engines.

I have never seen any water in the filter bowls even though our fuel management process has one or the other pairs of saddle tanks empty almost all the time unless we are going on a longer cruise. (We alternate the empty tanks because they're stainless, which is a whole other subject.)
Click to expand...

I tend to agree with your philosophy. Don't know for sure whether it has helped or not, but don't want to stop it and find out. I'm willing to spend a bit extra to avoid fuel problems. Do I use overkill to prevent them? Perhaps. But I don't have any problems. Fuel is the one thing that can potentially leave me stranded. Loss of engine doesn't. No other component on my boat does. But fuel problems would.
 
BandB said:
15.5 cents per gallon of diesel. Now the manufacturer's standpoint would be that by reducing consumption by 10% it saves you effectively 40 cents per gallon for a net reduction of 25 cents per gallon even considering the product cost. I don't know if that works out in reality or not.

Bill, has it reduced consumption in your experience?
Click to expand...

It did reduce our sooting issues with the gensets noticeably. In our case the fuel data was still being gathered when I let the boat. But others have seen use reductions.

It is expensive, so it's not for boats that do not go through a lot of fuel in a year.
 
Capt.Bill11 said:
It did reduce our sooting issues with the gensets noticeably. In our case the fuel data was still being gathered when I let the boat. But others have seen use reductions.

It is expensive, so it's not for boats that do not go through a lot of fuel in a year.
Click to expand...

9,000 gallons a month qualify? That was my usage in June and July.
 
Takeitesea said:
:) having a great summer! However, we are not traveling as much as we thought. I filled my fuel tank before winter storage and have used only half of the tank so far. Should I add any additives to protect the fuel or am I ok for the rest of the season? I will use the rest of the tank this season.
Thanks,
Don:
Click to expand...

If you're going to use additives in your fuel, you should add them when you add the fuel. You can't fix deteriorated fuel by adding something to it.

At this point I think you should add new fuel (and your choice of additive) to fill the tanks and dilute the old, untreated fuel.
 
Additives???? Last batch I bought for the old boat, 175 gal, the supplier said their diesel had biocide. Now I have another boat that needs 250-275 gallons. The boat is 1982. Since new she has had 1 gallon of Marvel Mystery oil added to every 100 gallons of diesel. When the injector pump was overhauled (2200 hrs) the tech said it was the cleanest he had ever seen. I do not know what the mystery is in Marvel but I am not gonna change, seems to work.
 
MMO

This stuff is cheap and it is good at dissolving carbon deposits. What is in it? 99% of it is two types of paint thinner: heavy naptha and stoddard solvent. <1% of it is ortho-dichlorobenzene. Though the dichlorobenzene is a very good carbon/sludge dissolver, they don't use very much of it because it is expensive and the chlorine atoms make hydrochloric acid in your engine. This in itself isn't an issue because all API approved motor oils contain a high amount of calcium-based detergents which neutralize the acid. It will shorten the lifespan of your oil though.

The product has been around a long time and has been very successful. The only trouble with it is the way it is marketed. It comes off as snake oil. This isn't the case. The product works, but with some caveats. It thins out your oil a little bit. A whole quart of it will thin your oil a whole grade (5W30 becomes 5W20). Also, it's not a very good lubricator so you only want to use it occasionally. Using it every oil change will definately increase wear and tear. You probably don't want to put it in a truck while you plan to do some heavy towing with it. And if you have a lot of sludge use it with caution. You don't want to use too much too fast and get chunks of sludge floating around in the oil lodging into worse places than it was before. Don't get it on your hands because it will absorb in your skin.

I saw lubrication testing that showed MMO was the worse. I used it and went through an IP faster than any other product.
 
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Re condensation I remove water from my fuel tanks by inserting a 1/8" copper tube bent to the ideal shape to reach the lowest corner on the fuel tanks. I hook up the copper tube to a little electric oil changing pump and pump out about a quart of fuel into a see through plastic jug. Sometimes I get a considerable amount of water. Once I got over a gallon and had to pump again. But usually I've got to look very carefully to see a tiny drop of water or so.

The large amounts of water come from leaks at my filler cap. Need to address that. It's a fault in the Willard design. The decks slant downward alongside the cabin as you go fwd so the water collects at the steps where you go up on the fwd deck. No drains either. Dumb design.

But water from condensation is next to zero.

I've never had water in my Racor filter.

If I wanted to get rid of my 2+ year old fuel how would I do it? I don't plan to but ...... sell it for $1 a gallon? What could be wrong w it if it looks fine?
 
From what I understand diesel doesn't go bad. I saw a boat that sat in a slip for 17 years and never had the engines run go to Alaska on old fuel. That proved it to me.
 
If your fuel looks clean don't use additives. Use it up this season and store mostly empty so you will have fresh fuel for next season.
The good thing about running with low fuel is that it will be cycled through the filters faster than if tank is full.
 
Mule said:
Since new she has had 1 gallon of Marvel Mystery oil added to every 100 gallons of diesel. When the injector pump was overhauled (2200 hrs) the tech said it was the cleanest he had ever seen. I do not know what the mystery is in Marvel but I am not gonna change, seems to work.
Click to expand...

The mystery is why anybody would pour it in their fuel.

http://www.jatonkam35s.com/DeuceTechnicalManuals/Diesel_fuel_additive_test.pdf

http://cdn.teachersource.com/downloads/msds/ENV-105MSDS.pdf

Or at least save yourself some money and just buy mineral oil and add some solvent to it then dump it in your tanks.
 
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According to lubricity studies done by the over the road trucking industry, Marvel Mystery Oil is one of the worst things one can put in diesel fuel. It actually reduces lubricity, and the studies show by how much. This and other evaluations of a large number of lubricity additives were posted on the Grand Banks owner forum a number of years ago, and may have been posted here, too.

When we bought our boat and were trying to learn everything we could about the care and feeding of our two FL120s, we were cautioned not to use MMO by acquaintances in the marine diesel industry. After reading the additive studies, we're glad we followed that advice.

I believe FF once posted the ingredients of MMO to this forum a long time ago. As I recall it was diesel fuel with red dye and wintergreen aromatics added.

In reading about MMO, I recall it was developed to prevent gummed-up carburetors in tanks and trucks during WWII, which all ran on gasoline. it was never intended to be a lubricity additive for diesel fuel. So far as I can tell, the whole MMO thing has become a shade-tree mechanic's urban legend.

Bob Smith at American Diesel continues to promote the use of MMO in diesel fuel. He's a real expert on Lehman engines, given that he worked for them and was involved in many of their marination projects. But when it comes to MMO, I believe he is dispensing very bad advice.
 
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Marin said:
According to lubricity studies done by the over the road trucking industry, Marvel Mystery Oil is one of the worst things one can put in diesel fuel. It actually reduces lubricity, and the studies show by how much. This and other evaluations of a large number of lubricity additives were posted on the Grand Banks owner forum a number of years ago, and may have been posted here, too.
Click to expand...


Yeah I think I somebody post a link to that test and and the MSDS for MMO just recently. ;)
 
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