Fuel additives? Yes or no

[Greg Mason]

My good friend was a diesel motorhead. His feeling with biocides and algaecides was that the return fuel to the tank was engine warm and not seawater cold, and the warm temperature could breed growth in the diesel. Age of fuel when stable is less of an issue, and those of us in the northern climates would do well to address the condensation formed due to the temperature changes. Thanks Rob for the information on jet fuel and diesel, I always wondered when filling tanks in An Hoa, why JP-4 smelled like diesel, or at least keroseneish.

[MicHughV]

...this discussion seems to disregard the value of a good diesel filter/water separator or two...

[Bentwings]

I’ve run my own private 1 ton diesel truck 450k miles here in the USA. I’ve been through all the diesel fuel changes. The first of de-sulfuring resulted in many of the first generation electronic fuel injection pumps failing. We had to run various additives and there were many independent tests to demonstrate effectiveness. Then came Early bio diesel gelled which at just under 30 deg F . We had to use anti gel for a while. I got caught on a back road in -20 deg F with gelled fuel and plugged filters. Believe me it was a cold day in hell.
Within a year or so the refineries came back with winter grade fuel. I noticed no difference in performance other than reduced mileage. Years following bio diesel increased to as much as 15%. Mileage further decreased but mfg responded with common rail motors that operated at far higher injection pressures and multiple injections per cyl firing. This improved mpg quite a bit. Emissions became more important and now the newer diesels from 2007 and later run DEF additive right at the pump. So obviously necessary for the later models.

As far as boats if it’s an older boat you are stuck with bio diesel a minimum of 5% max of 15%. Most inland marinas here do not have diesel. You must call a local oil company and they will come to you with fuel.

Here, I asked the Dept of Motor Veh. When I got my boat registered if I could use off road fuel (Red Fuel) which does not have road tax added. In the USA you cannot use Red Fuel. Even though the boat is not a road vehicle. You cannot deduct the tax either. So you will get standard fuel treated for the area and temperature.

Bottom line you probably should use biocides if you have very long storage times. I used to have my own test samples but gave up. I just drive the truck and fill up as necessary. If I had a boat that I didn’t use often I would test samples to see what I needed. There dozens of additives but those for aging fuel would be all I would be interested in.

Our marina is only a short distance from two jet airports but I’d guess it might be hard to get fuel for non flying or “public “ use let alone a tank truck to deliver it. I’m not sure if the local oil companies would deliver JP-4 if that’s what you wanted. You may have to go through Homeland Securities for a permit. They are on top of unusual fuel situations. Even racecar fuel is regulated.

Best bet here is if you are traveling by boat in the USA plan your fuel stops ahead.

[a64pilot]

JP-4 I think is hard to find, it used to be the military standard Jet fuel, but early 90’s, maybe the Army went to one fuel, that being JP-8. It’s burned in all Army Diesels as well as of course the M-1 tank.
JP-4 was a gasoline based Jet fuel, NATO F-40, Civilian Jet-B, that the Army used forever as I believe it was cheaper than JP-8, which is the same as Civilian Jet-A+

All Military fuel has biocides in it, for some reason you need to pay extra for it in Civilian fuel, assumption is I guess if you know for sure your burning it all this morning, why pay for the Biocide? Military learned long ago that if you don’t have the Biocide, it’s going to bite you eventually.

I like Biobor jf as I believe it was first introduced for aviation fuels in the 1960’s, its been around a long time and I know it’s not snake oil.

[Carl-T705]

It's amazing to me that people with diesel engines know so little about the fuel they burn. You definitely need to treat with biocides, especially since the US government has mandated biodiesel be added to all diesel fuels, 5-15 percent bio.I treat every two months with a biocide. Cetane boost is pablum for the operator. I've never seen any power enhancement. The few that did anything performance wise never lasted very long on the market because of pricing. Many people think additives remove water and moisture, not the case it merely breaks the water down so it can be burned along with the fuel. If you run fuel with algae in it, it not only attacks the fuel system, it gets into the crankcase and destroys engine parts like bearing surfaces. High heat, hot oil will not kill algae once it is in the crankcase. Don't believe me, do some real research.... like I did.
I burn about $35,000/ year of diesel fuel. The only additive that I've used that shows improvement in fuel quality right now is Sea Foam for gas and diesel fuels. Marine Sta-bil for fuel that is stored for extended periods is a quality product as well. There is no such thing as branded diesel fuel, it all comes out of the same pipeline, different oil companies add their own additives to fuels to make it their own. ( in the US)

[UFGator]

Originally Posted by MartinR

No, they are not. Jet fuel is kerosene which is much lighter, has a lower flash point, and will destroy your injection pump quickly, as it has very bad lubricating properties. Yes, some diesels can run on it, but not the normal small boat engines.

According to Google (they know everything) it is basically the same thing:

Diesel gas is heavier than jet fuel, with a higher number of slightly larger hydrocarbon chains, though both are primarily paraffin oils (kerosene). Diesel is more viscous than jet fuels.

[Garbonz]

Originally Posted by Carl-T705

It's amazing to me that people with diesel engines know so little about the fuel they burn. You definitely need to treat with biocides, especially since the US government has mandated biodiesel be added to all diesel fuels, 5-15 percent bio.I treat every two months with a biocide. Cetane boost is pablum for the operator. I've never seen any power enhancement. The few that did anything performance wise never lasted very long on the market because of pricing. Many people think additives remove water and moisture, not the case it merely breaks the water down so it can be burned along with the fuel. If you run fuel with algae in it, it not only attacks the fuel system, it gets into the crankcase and destroys engine parts like bearing surfaces. High heat, hot oil will not kill algae once it is in the crankcase. Don't believe me, do some real research.... like I did.
I burn about $35,000/ year of diesel fuel. The only additive that I've used that shows improvement in fuel quality right now is Sea Foam for gas and diesel fuels. Marine Sta-bil for fuel that is stored for extended periods is a quality product as well. There is no such thing as branded diesel fuel, it all comes out of the same pipeline, different oil companies add their own additives to fuels to make it their own. ( in the US)

Out of the same pipeline and with some commingling at the front and back but the refineries and the pipeline companies know whose fuel is where in the pipeline and where it goes at the end. Really, I did research to, and not on the internet.

[boat driver]

Lot of interesting opinions out here.
couple injections/clarifications-
1) refineries do not put additives in unless mandated because they are not sure the final use of the fuel.The military specifies additives that meet their needs.
2) commercial vessels that utilize large amounts of fuel specify the additives they need- and when filling the vessels samples are taken for lab analysis to assure the fuel meets specs before use. Fuel out out spec is often returned to the supplier or reformulated in the tanks by blending till it meets specs.
3)pipeline fuels are not commingled beyond a lesser quality is generally pumped last. with heavier fuels/crudes /chemicals pigs are used to keep cargo separated
4) Bio diesel is not mandated everywhere in the US- but use of it in the recreational marine world is probably effected by the states that mandate it on the road.
5) Biodiesel does not respond well to biocides to date- if it gets growing bio-growth-have fun hot fuel washing the tanks and fuel system- what is the difference? it looks like honey. so avoiding it is best and if using- avoid storing it long term, particularly in warmer latitudes.
6) red dye is simply non-taxed fuel, as is green dye. use of red dye on any public roads is not legal. IN the marine industry USA green was also utilized at one point, but that has been eliminated. Due to interstate commerce, individual states may not mandate a tax via color in the tanks- it may institute a tax at the pump if desired.

[Simi 60]

Originally Posted by az_r2d1

This is key. Preventive action is what it is all about.
If you can afford a boat with twin 490hp engines, you can afford a good biocide (which is still a fraction of your fuel cost).

Silly statement.
Are you claiming the guy on a small boat with a 15hp diesel can't afford biocide?
What about the guy with a single 325hp diesel?

Preventative action for me is not getting water in the tanks in the first place.
No deck fillers, its a stupid place for a filler.
Regularly replaced Orings
Crud sump built into the tank, drained and checked every few months
Good filtration.

I have as yet never used a biocide and never had any sign of crud or a clogged filter.

[boat driver]

Originally Posted by Simi 60

Silly statement.
Are you claiming the guy on a small boat with a 15hp diesel can't afford biocide?
What about the guy with a single 325hp diesel?

Preventative action for me is not getting water in the tanks in the first place.
No deck fillers, its a stupid place for a filler.
Regularly replaced Orings
Crud sump built into the tank, drained and checked every few months
Good filtration.

I have as yet never used a biocide and never had any sign of crud or a clogged filter.

Simi,
obviously you have never fueled in non-popular locations.
Water is ever present in fuel from the refinery, logistics, storage, and your vented tank. the magic question is "how much"
mentioned above are simply your end controls-

[timb7734]

I use StarTron as well, and have for many years, I never worry about condensation, or have ever had algae growth. The best fuel however has some low percentage of moisture naturally. I store in the UP of Michigan in winter, and LaBelle Florida in summer, and every time I lay up with whatever is in the tank. I do not feel treatment is necessary during use of the boat, just when the vessel will be in storage for several months. Diesel fuel degrades about 1% of its cetane each month without treatment.

[Simi 60]

Originally Posted by boat driver

Simi,
obviously you have never fueled in non-popular locations.
Water is ever present in fuel from the refinery, logistics, storage, and your vented tank. the magic question is "how much"
mentioned above are simply your end controls-

She's an ex trawler that was working the gulf of Carpentaria so has been refuelled in some pretty remote locations.

South east Asia has some pretty remote filling spots and stories of fuel issues are legion.
Interesting that several long term cruisers I speak to up there, some with 25 years in the area claim to have had no issues and don't use biocide but they are the ones using 500fg or larger filters whereas the ones with the endless problems do not.

Something I am looking at installing prior to our trip up is a 200mic prefilter to get the big stuff before it hits my dual 1000ma 30 mic and 10mic and dual on engine 2mic filters.

https://www.boatstore.com/racor-3002...g-200-mic.html

[Simi 60]

Also wonder how these would go stuffed into the filling port, insert nozzle and have diesel run through 150mic mesh

https://www.ebay.com.au/itm/100-150u...edirect=mobile

Yes, its an aquarium filter but it uses nylon mesh as do the diesel mesh filters and 10x the cost.

[Compass790]

Originally Posted by Simi 60

Also wonder how these would go stuffed into the filling port, insert nozzle and have diesel run through 150mic mesh

https://www.ebay.com.au/itm/100-150u...edirect=mobile

Yes, its an aquarium filter but it uses nylon mesh as do the diesel mesh filters and 10x the cost.

I use a coffee filter in a funnel ( I'm cheap coz i have to be) when filling tank & used to be surprised at how much dirt came out of the fuel. Now I just expect it. As long as your aquarium filter flows enuff yea go for it

[redneckrob]

Originally Posted by Compass790

I use a coffee filter in a funnel ( I'm cheap coz i have to be) when filling tank & used to be surprised at how much dirt came out of the fuel. Now I just expect it. As long as your aquarium filter flows enuff yea go for it

Many aircraft have a "go/no go filter" just after the fill nozzle that will actually stop fuel flow if the fuel is contaminated. You're doing a decent approximation of that at a far lower cost, so not a bad idea.