Fuel Additives

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dlandersson
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Fuel Additives

Post by dlandersson » Tue Feb 05, 2019 11:08 am

Saw this blurb:

Modern fuel has a relatively short shelf life without a preservative. In as little as six weeks modern petrol can start to thicken and block our engines internals. Diesel can suffer from organisms growing inside it, which can also cause a diesel engine to grind to a halt. And no engine, whether it be petrol or diesel, will enjoy the taste of water mixed with its fuel.

The issue is compounded somewhat by modern engines, that deliver extremely precisely measured amounts of fuel to minimise the amount of fuel burned during operation. These small, precise parts are certainly more prone to blockage than engines of old, so we need to be extra careful about how we treat fuel that is left in our boats tanks over the winter.

I use Sea Foam - a lot, based on the strong recommendation of the man who taught me to sail my X. I am open to a better product if anyone can suggest one.

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NiceAft
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Re: Fuel Additives

Post by NiceAft » Tue Feb 05, 2019 11:26 am

The question I have is, are you happy with the performance you now get? If so, why change? I am fairly sure that if there is something out there better, it will only be so, incrementally. Unless you are retired, and have nothing else better to do, get a hobby and be happy. :D

Ray

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Tomfoolery
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Re: Fuel Additives

Post by Tomfoolery » Tue Feb 05, 2019 1:54 pm

Sounds like a marketing blurb. I have gasoline in my 4kW 'portable' generator that's often more than a year old, and it starts and runs just fine. Smells OK, too (though I miss the smell of leaded regular from when I was a kid). My generator isn't a high-tech fuel-injected modern engine, though.

I do treat with Stabil, and I use ethanol-free gas for all my small engines so it's less likely to absorb water, and I do the same with my OB fuel (which I fill and store for the winter for generator use if needed in an ice storm), but that stuff doesn't suddenly turn to varnish in a matter of weeks. That's been my experience after many years of neglecting my engines, at least in the sense some product marketing reads.

Diesel has always had an issue with microbes growing in/on it, and there are treatments available. But often, nothing short of opening the tank and cleaning it out is completely effective, along with filter changes. Biodiesel only makes things worse, from what I know, including water retention, but a little biodiesel in dinodiesel does add lubricity to ULSD, which is a good thing. Not every diesel engine is rated for more than B5, though - Mercedes Benz makes that quite clear, though their Sprinters are sold all over the country and biodiesel greater than B5 is about all you can get in certain parts of the country, up to B20 (I think B10 is most common in the mid-west). Water is absorbed in diesel as a matter of course, by the way.

I've used Sea Foam to clean out old engines, though I don't know how effective it actually is without a control group of other old engines. :|

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mallardjusted
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Re: Fuel Additives

Post by mallardjusted » Tue Feb 05, 2019 5:23 pm

Ethanol is a problem in gasoline engines, especially if it is stored for awhile. Around our part of the country it is extremely hard and/or inconvenient to find non-ethanol fuel.

For years I've used Marine Stabil, and occasionally Seafoam. After a lot of research, the last couple years I've switched over to Startron (via amazon or walmart). It's as good as Stabil, but costs less per gallon. They are both good for storing fuels. I also pour my older fuel into the car tank rather than store it too long. I now only use Seafoam one time in the spring after the outboards, lawn mower, power washer, etc have been stored a long time. Seems to "tune up" the small motors (especially the lawn mower! ........

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RussMT
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Re: Fuel Additives

Post by RussMT » Tue Feb 05, 2019 10:29 pm

I have used both Seafoam and Sta-Bil. Never had a problem with either. However, I have noticed Sta-Bil has an expiration date. So I toss it after a year or so.

I am now considering a water separator. I think that might have more merit than additives.

--Russ

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RussMT
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Re: Fuel Additives

Post by RussMT » Tue Feb 05, 2019 10:56 pm

Doing a bit of research and Star Tron seems to get high marks.

AND...8 oz @ $10 treats 128 GALLONS! That's a great bargain.
AND the shelf life of this is indefinite. As long as it does not freeze and you keep it out of the sunlight it will last a long long time on the shelf.

They claim you can add it to fuel with Sta-Bil in it. I may get some.

--Russ

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dlandersson
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Re: Fuel Additives

Post by dlandersson » Wed Feb 06, 2019 12:46 pm

My experience with Seafoam. :)
mallardjusted wrote:I now only use Seafoam one time in the spring after the outboards, lawn mower, power washer, etc have been stored a long time. Seems to "tune up" the small motors (especially the lawn mower! ........

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yukonbob
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Re: Fuel Additives

Post by yukonbob » Thu Feb 07, 2019 9:25 pm

Big problem is once the ethanol is gone so is the stabilizer leading to mid-fires (usually pre ignition due to unstable fuel hitting hot cylinders) which can damage seals, backfires etc. Most common is an error code from the knock sensor. This is especially bad in high compression, high rpm engines like motor bikes (crotch rocket variety) outboards etc. Almost every vehicle today is a high compression engine. There is a big misconception that high octane fuel contains more energy, False, the higher the rating the more stable it is, this is why high performance engine that fire very fast and at very specific times require a fuel that will ignite at the exact time, not before, not after.

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Herschel
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Re: Fuel Additives

Post by Herschel » Thu Feb 07, 2019 11:08 pm

I have used marine Stabil, along with an injector cleaner recommended for my brand of engine (Yamaha), non-ethanol gas exclusively, kept my tanks topped off pretty well, run my engine faithfully every three weeks or sooner at speed, and do my 100 hour service on time by a qualified marine tech. I have never had a problem with my gas or my engine! :) :) :) ... Yes, I knocked on my wooden desk three times! :D

Interim
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Re: Fuel Additives

Post by Interim » Tue Feb 19, 2019 2:01 pm

I use Sea Foam, just because it seems like a better name for a fuel additive on a boat.

But I also put in the highest grade gas available (91, typically). It costs a lot more, but since I probably burn 5 gallons all season it is not really an issue. I can hear the difference in the motor, and feel the smoother power.

--john

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Herschel
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Re: Fuel Additives

Post by Herschel » Tue Feb 19, 2019 6:43 pm

Interim wrote:I use Sea Foam, just because it seems like a better name for a fuel additive on a boat.

But I also put in the highest grade gas available (91, typically). It costs a lot more, but since I probably burn 5 gallons all season it is not really an issue. I can hear the difference in the motor, and feel the smoother power.

--john
Interesting. I only have one choice of octane, if buying non-ethenol gas. Not even sure what that is, so I can't comment on the difference in octane for our marine engines, but i believe I have the same experience with my truck when towing my travel trailer that you have with a higher octane gas. My truck mileage goes up and the power seems greater. I always fill up with high test when towing in hilly or mountain terrain.

Starscream
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Re: Fuel Additives

Post by Starscream » Wed Feb 20, 2019 7:57 am

Herschel wrote: Interesting. I only have one choice of octane, if buying non-ethenol gas. Not even sure what that is, so I can't comment on the difference in octane for our marine engines, but i believe I have the same experience with my truck when towing my travel trailer that you have with a higher octane gas. My truck mileage goes up and the power seems greater. I always fill up with high test when towing in hilly or mountain terrain.
As an amateur hypermiler I've done a fair amount of research into octane and the effects on mileage. All the independent research that I have found says that the Octane Rating of the fuel makes no difference in the fuel economy or power of the car. For cars that need high-octane fuel to reduce pre-detonation (knocking), it's important to use it, but that's really its only function.

My driving is a fair split between highway driving and city driving, and using my amateur techniques I have achieved these mileages (yes, I record fuel consumption year-round! It's the engineer in me I guess).
2004 Toyota Echo, manual transmission - averaged 43.5 MPG
2015 Mitsubishi Mirage, manual transmission - averaged 45.2 MPG (replaced the echo)
2017 Mitsubishi Mirage, CV transmission - averaging 45.3 MPG (replaced the 1st mirage)
2018 Ford Fusion Energi, CV transmission, averaging 336.1 MPG :D yup...been to the gas station twice since last May. (admiral now drives the 2017 mirage)

With the Echo, I experimented with premium vs. regular, and the results were no better than random. Sometimes better, sometimes worse, but driving technique and external conditions were waaaay more important. I determined after looking at the numbers, even though my brain wanted to say the premium was "better" for my car, that premium fuel made no provable difference. In my neck of the woods the only non-ethanol fuel is the high-octane premium fuel, so I do use that in my Fusion since I only fill up once every 4,000 miles or so, and I don't want the ethanol in the tank.

I've had a lot of fun experimenting with different hypermiling techniques while not getting other drivers mad (I'm not a fanatic, just do it for fun, when it's appropriate). I used to drive the tow-beast Dodge Durango as my daily driver, then I did the math and found that I could own a second economy car, and the car payments, registration, and insurance on the new "econobox" would be less money than the amount I saved on gas by driving the small car 80% of the time, and the truck only when I needed it: MacTrips and once in a while some real work.

Have to admit it takes some self-actualization to be just as happy with a mini-car as driving a big manly truck.

Interim
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Re: Fuel Additives

Post by Interim » Fri May 17, 2019 8:51 am

That's interesting data on the fuel types. I have two counter points to consider:

1) fuel isn't just about efficiency. I think how it affects the engine is a factor. Does higher octane stay more stable over the long hot summer? Does it cause less tarnish on carbs, etc?
2) Superstition. Whatever you feel on land may not apply on the water. Embrace the unknown. If something works for you, don't change it.

--john

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Jeff L
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Re: Fuel Additives

Post by Jeff L » Sat May 18, 2019 10:49 am

8)
RussMT wrote:
Tue Feb 05, 2019 10:56 pm
Doing a bit of research and Star Tron seems to get high marks.

AND...8 oz @ $10 treats 128 GALLONS! That's a great bargain.
AND the shelf life of this is indefinite. As long as it does not freeze and you keep it out of the sunlight it will last a long long time on the shelf.



--Russ
I use Startron in all of my small engines and all of my older trucks and cars. I am also using

ethanol free gas, now that it can be had where I live, in my small engines. Not in my older

vehicals yet. I have to check if my new truck can handle ethanol free fuel or no... 8)

Jeff

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