Do You Really Need Fuel Additives ?

[off-the-grid]

I guess this is the week of starting train wreck threads for me. Anyway what are the opinions here? I'm noticing that I'm really starting to collect bottles of potentially unnecessary and not exactly cheap stuff that's eventually going to add up.

I guess at least a little Ethanol treatment for an older outboard is a must, but...

On one side I've heard people (even very experienced long time cruisers) recommend everything from stabilizer, cetol, octane booster, etc., etc., etc.

On the other, even a mechanic, recently told me to be VERY careful what you add to your fuel. I've heard some people even say to use nothing. Just keep an eye on your filters, suck the junk out of the bottom of the tank when you start to see **** in them, and just don't store long term with a full tank. Otherwise just dump the old fuel and assume that it's not any good.

[speciald@ocens.]

If you turn over your fuel often, then you don't need stabilizers and anti-algae agents.

[S/V Illusion]

Originally Posted by grunzster

On one side I've heard people (even very experienced long time cruisers) recommend everything from stabilizer, cetol, octane booster, etc., etc., etc.

.

I am in favor of the cetol additive - that should keep all those pesky boaters away from my favorite anchorage.
Seriously, keeping fresh fuel in the tank is all you need do. Anything else is just a waste of money or how advertizing influences you. If you feel compelled to add anything, cetane booster won't hurt in small quantities.

[marshmat]

I've never felt the need to add anything (other than 50:1 TC-W3 oil where applicable) to fuel during the boating season. As long as the fuel is clean and isn't going to sit for more than a few months, it ought to be fine on its own. If you're carrying more fuel than you can burn in a season (possible for some diesel boats, but I've never seen a gas engine boat that does), you either have too much tankage or need to polish it through the filters now and then.

I'll put a shot of stabilizer in the last tank before winterization, just to make sure the carb isn't full of fuel varnish come springtime. But that's about it.

[fishwife]

When my boat is topped up, that's 2650 gallons and I've never had a problem with fuel, even when it's taken 9 months between fuel stops. If you have the space and want belt and braces, a simple fuel polishing system takes care of any gremlins. In warm waters I may give some consideration to an anti-bacterial additive. If you've never cleaned your tanks, it's probably a good thing to include in your winter 'to do' list.

P.

[capn_billl]

I use additives alot, but I don't turn my fuel over that often. I've had to use additives to save older fuel that was causing knocking.

[Healer52]

YMMV. My everyday truck is a diesel, with a 100 gal tank in the bed. I add Pri-D stabilizer whenever I fill it (about yearly). The truck also has a 60 gallon replacement tank that I use most of the time.

I also store diesel at home (for the tractor and generator) and I add Pri-D to it, and Pri-ocide. It sits quite a long time between refills. I polish the stored fuel semi-annually.

In the vehicles (my other vehicles are diesel too) I add cetane booster (Ford PM-22A or equal). The trucks don't seem to mind. I don't add it to the tractor (Kubota so it has a Beta engine) or generator (Cummins).

I pretty much followed the same policy on the boat. Pri-D, priocide since a tank could last me a year, no cetane booster.

And I add Pri-G to the gasoline I stored for the outboard.

Pri-products seem to work well.

[Kettlewell]

I absolutely believe in adding StaBil to any gasoline I use in my outboard. I've been doing this for something like 20 years and I've never had a major problem due to the gas going bad. At the end of the season I just double the StaBil dose a bit before I put the engine to bed and let that gas sit in the carb over the winter. It always starts right up and runs perfect in the spring. Done this for both 2 and 4 stroke outboards, but on 4-strokes it is even more critical because the carbs don't like any teensy particles or crud.

I carry 115 gallons of diesel, so a chunk of it might sit in the boat over the winter. I'm now using FPPF Marine Formula in my diesel, and it has a nice smell. It was rated well on several diesel engine sites. The added lubricity is useful with low-sulfur diesel. Can't say for sure it is really doing much, except my engine seems to be running fine. I tried SeaFoam in my fuel for a few years, and I must say for some reason the engine exhaust generated a lot less soot on the transom, but I can't claim that was directly related to the SeaFoam. I think if you are burning through your diesel regularly probably the most important thing to do is get it at a place that pumps lots of fuel, preferably to commercial users or large sportfishermen. Neither type of customer will put up with bad fuel.

[off-the-grid]

You guys have some BIG tanks! I only carry 55 gallons, and that includes 3 5 gallon jugs.

[matauwhi]

G'day, mates. I have 3, 100 gallon diesel tanks. Currently 1 is empty. I rotate the other 2 and I keep them topped up whenever I can to minimize the air space (which brings along moisture). I used roughly 6 gallons a week running the generator and motoring when the wind won't take us were we want to go. I also pump a a bit off the bottom everytime I change the engine oil. I quit using stabilizers 5 years ago and haven't had any trouble yet. Cheers.

[kapnd]

I dont use them, and dont think its a good idea to.
Your best defense is to keep tanks as full and clean as possible, and make sure your filtration is up to par.
Some good reading on the subject at boatdiesel.com in the articles section.
Oh, allmost forgot that additive use can void some warranties as well!

[sailingaway221]

I live in the tropics and think that for me algae treatment is a must. I have very well sealed tanks, but if I don't get out and use it a lot there always seems to be some growth in there. It's the only thing i use.

[kapnd]

and just don't store long term with a full tank. Otherwise just dump the old fuel and assume that it's not any good.[/QUOTE]


I must disagree with that, storage on an empty or partially empty tank is an invitation to disaster. Store full with an additive intended for storage. (StaBil).
A full tank has very little airspace, so condensation will be minimal.
Diesel fuel will keep much longer than you think, and certainly longer than gasoline, no need to dump the old stuff.

Sailingaway, sounds like you could use a polishing system, a small pump and a good filter is good insurance when you're far from help and probably not getting the cleanest fuel.
Algae treatment causes even more trash to your filters, but will not be necessary if there is no water in the tanks. The bugs are in the water, not the fuel. Treat the cause, not the symptom!

[sailingaway221]

Kapnd... Once I started adding the additive my fuel algae issues went away.... I do polish fuel.. I have 2 filters into the engine and 1 on a cross feed that runs both ways.... The additive really helped me though!

[capt_douglas]

It would depend on how much fuel you use, how good your filter system is, how new the diesel is, and how clean the fuel is at the location you're at.

If you got through a tank of diesel a month then you might not need the stabilizer. Ditto on the gas. If you've got a good prefilter or polishing system then it might not be a problem. If the diesel/gas is fresh off the boat or from the refinery, you might not need it. If the fuel you get contains no water, crud, stones, or gunk, you might be OK.

In my case, I went through 50 gallons of diesel every 3-4 months so I used a stabilizer. I had a fairly good prefilter but no polishing system so I used a stabilizer. I had no idea how fresh the diesel was so I used a stablilizer. Having had my fuel tank cleaned due to dirty fuel I now use a Baja filter (prefilter that removes most of the water and non-diesel from the supply to the tank) in my fuel filling.

I change my Racor filter every 100 hours or when the guage starts showing blockage. I use a lot more gas/month than diesel but have had the in-line fuel filter start to show blockage and gunk collection after a few hours so I watch that as well. I don't tend to add a gas additive as I use more of it than diesel.

You can get gas and diesel additives/stabilizers and while I recommend them I don't have an instance where not using them caused or prevented a problem. I consider it cheap insurance.