gas addatives

Nov 22, 2011
1,192
Ericson 26-2 San Pedro, CA
Stabil and Seafoam definitely works. My outboards run perfectly on E10, just be sure its fresh and/or has additive. I ran E10 in my racing motorcycles as well and my motors smoked ALL other mc's no matter what thay ran! Chief
Using Stabil, what's the longest you would recommend leaving gas in the outboard's tank before draining/tossing it? I have a Honda 2.3 hp 4-stroke with a built-in tank. I've begun using the marine version of Stabil (the blue stuff). I use the outboard only occasionally, and can sometimes go a few months or more without using it.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
Using Stabil, what's the longest you would recommend leaving gas in the outboard's tank before draining/tossing it? I have a Honda 2.3 hp 4-stroke with a built-in tank. I've begun using the marine version of Stabil (the blue stuff). I use the outboard only occasionally, and can sometimes go a few months or more without using it.
there are a lot of factors to consider, but with stabilized ethanol free gas, kept stored in a cool environment, 2 years+.

if you use seafoam in it, it will help in the stabilization of the fuel and keep any deposits from collecting inside the system.... it will help keep things in suspention so it will pass thru when you start it again.... and it will easily start up after a long period of not being used.
personal experience.

I mix my 2 cycle gas in 6gallon cans, and it has sat 4 years once (while i was going thru a life changing divorce:D:D WOO HOO!) and it was fully usable when I decided it was time to trim the trees and clean up the orchard.... and start the outboard so I could go fishing.

I will let others who have had better luck than me, answer about the ethanol fuel product.
 
Nov 22, 2011
1,192
Ericson 26-2 San Pedro, CA
there are a lot of factors to consider, but with stabilized ethanol free gas, kept stored in a cool environment, 2 years+.

if you use seafoam in it, it will help in the stabilization of the fuel and keep any deposits from collecting inside the system.... it will help keep things in suspention so it will pass thru when you start it again.... and it will easily start up after a long period of not being used.
personal experience.

I mix my 2 cycle gas in 6gallon cans, and it has sat 4 years once (while i was going thru a life changing divorce:D:D WOO HOO!) and it was fully usable when I decided it was time to trim the trees and clean up the orchard.... and start the outboard so I could go fishing.

I will let others who have had better luck than me, answer about the ethanol fuel product.
Followup: So with a product like Seafoam and/or Stabil, would you still recommend shutting off the valve to the tank and running the carb dry, or would it be better to actually leave the treated fuel sitting in the carb? Or does it matter? Normally I'd run it dry.
 
Mar 26, 2011
3,400
Corsair F-24 MK I Deale, MD
Hi Brian,

From what I can see they just looked at the corrosion issues that may emerge from E-10 use, specifically to brass, steel, and aluminum. Solids they found in the fuel were actually the corroded metals. They did mention that an industry trade group had formed to develop standards around fuel additives and claims that they could clean fuel systems, but this was back in 2012 and I didn't see any other update.
Yes, additives are useless in preventing phase separation (there are a few that can or may, but they have the side effect of accelerating corrosion and oxidation--throw those away as fast as you can). That was the limited conclusion of the first article. It was NOT a conclusion that additives are not valuable.

The following all have something to do with fuels.

Nov 2008
Aug 2012
Dec 2012
July 2008
Aug 2013

I did the testing.

I'm am just finishing an up-date article that should publish in Fall 2015 that includes corrosion testing, diesel bio-cides, and long-term aging tests (3-4 years, accelerated). Over-all winner will be selected, those that were "recommended" in all phases of testing.

I was probably the most skeptical of all, expecting to find pure snake oil. Instead I found a few brands the consistently produce results. All of the testing was quantitative (based upon actual or modified ASTM methods). There were reams of data, though little of the detail makes it past the editors space limitations--to all of you data geeks, sorry.

I also found some snake oil and some that actually make things worse. The NMMA is working with OEM and additive manufacturers to come up with actual standards since 2012, but there are disagreements, to say the least.

Claims that a product can fix motor problems or dissolve varnish are beyond PS testing. My opinion, based on the testing that I have done:

  • Additives are for prevention, not fixes. You cannot recombine separated fuel nor should want to. They are not for cleaning tanks. They are to prevent corrosion. They can prevent oxidation and varnish formation (the next articles explains how--the key is metal activators).
  • Additives should be used every time. Adding a shock dose to solve a problem is bad.
  • 1/3 are worse than nothing, 1/3 are a waste of money. and 1/3 are worth every penny.
As for ancidotal evidence, I've been using the PS "best choice" products for years and I'm thrilled. Zero fuel problems (4 engines) since I made the change, and it was problems that peaked my interest. I also added an in-line filter to my 3.5 Merc and a silica gel vent filter to the main tank. And life is good.

As for draining carbs, if you read the OEM guidance, most have changed their position on that, and ONLY recommend running dry for long term storage. It has to do with the fact that you never get it 100% dry, and what you leave will dry, leaving varnish. But that will turn into an "anchoring thread."

Personally, I use Biobor EB.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
Follow up: So with a product like Seafoam and/or Stabil, would you still recommend shutting off the valve to the tank and running the carb dry, or would it be better to actually leave the treated fuel sitting in the carb? Or does it matter? Normally I'd run it dry.
with the treated fuel, ive never seen where it makes a lot of difference.... like i said earlier, my engines sat for 4yrs plus with gas in them and they fired right off after charging the batteries and a couple extra cranks...

I think the temperature of the environment where they are kept has a lot to do with it.... cool is best and if warmer you may be better off running the gas out of the carb... there will always be a bit of fuel in the carb, until it evaporates out, and this is something that only the environmental conditions in which it is kept will determine...

for long term storage, when you know without any doubt that it will set for more than just the winter season, I would recommend running the carbs dry.... but if you forget or dont get to it, its not too big of worry.... and thats the beauty of using dependable additives, because they will take care of the problem when we arent so dependable:D....
 
Nov 26, 2012
2,315
Catalina 250 Bodega Bay CA
I personally run my motors dry and open the carb drain if I expect to not use them for over a month. I run all of them dry to put away for the winter. I have one 2 stroke and two 4 strokes and use additives. I keep no gas over winter. It all goes in my truck and I get fresh stuff next spring. My motors run great!
In my racing bikes, 2 and 4 stroke, I also ran acetone as a high octane additive just before hitting the track as it evaporates very fast.
Chief
 
Mar 26, 2011
3,400
Corsair F-24 MK I Deale, MD
I personally run my motors dry and open the carb drain if I expect to not use them for over a month. I run all of them dry to put away for the winter. I have one 2 stroke and two 4 strokes and use additives. I keep no gas over winter. It all goes in my truck and I get fresh stuff next spring. My motors run great!
In my racing bikes, 2 and 4 stroke, I also ran acetone as a high octane additive just before hitting the track as it evaporates very fast.
Chief
If you live in California, there is no winter, at least not to my understanding (ice). Sail all year. I do, and I get ice.
 

mm2347

.
Oct 21, 2008
241
oday 222 niagara
Lots of info. In terms of what I "think" is there are at least three (3) major problems w/ ethanol fuel: 1) it attracts and absorbs water into the fuel to a point but beyond that the water, not the ethanol will separate. The water in the fuel isn't the greatest but the motor will burn the mixture. The separated water can and often will cause many problems. I believe that I read that nothing can make that water mix back into the fuel. 2) Ethanol will act as a solvent and go after much the crap that has deposited in the fuel system from the fuel can-tank thru the carb. This gunk, often mixed w/ a little water, can really mess things up. 3) Ethanol will eat a lot of older fuel system parts and even some of the new stuff. Motors w/ fuel or fuel systems that sit give the alcohol-ethanol an increased chance to "eat away". ( Of course once the gunk is gone so is one of your problems.) and have a greater chance to absorb water.
There were also some articles in Prof. Boat Builders on this subject but I like some others have a trouble searching such things.
 

mm2347

.
Oct 21, 2008
241
oday 222 niagara
I have just read Thinwaters post and its prob part of what formed my question on useless additives. 2/3s of the stuff is useless or worse and many of the other products are used for the wrong reasons. Do any of the additives solve the three ethanol problems I listed above? I also tend to use PS " best choice" products. PS does not accept advertisement. Most of the other mag. have some very good people on staff but they are handcuffed by the advertisers who pay the bills.
 

mm2347

.
Oct 21, 2008
241
oday 222 niagara
Notice he states he does not use alcohol additive fuels. No wonder he can make such a statement! Would you like to share your cost per gallon? You are not even addressing the issue we are discussing. He further indicates his lack of understanding of gasoline by stating he uses PREMIUM. He obviously is not aware that, that is overkill! My condolences, Chief
Chief: I buy PREMIUM only because in my small town area its the only way to buy fuel ethanol free. I own a sailboat and don't use my motor much so the small cost is worth the lack of trouble. What is the cost of ethanol fuel plus an aftermarket additive that may or maynot work? I'm also sorry I came across as making a statement. I wanted to ask a question and hoped to get information.
PREMIUM fuel has a higher octane rating. That means that it will ignite at a higher temp. The low compression of my motor does not need the higher octane of PREMIUM fuel. And Chief don't feel sorry for me. I can afford 3 or 4 dollars a month.
 

Zed

.
Aug 19, 2015
96
West Wight Potter 19 Bar Harbor
Depends on your experience that is ethanol caused.....

While Blue Stabil may in fact make my Honda 5 HP work with ethanol, I had an experience I don't want to repeat that came from ethanol in the gas. Wind died, motor refused to start, ended up drifting in the channel head toward a sharp rocky shore, and in the nick of time was rescued by the Coast Guard.

Once you have an experience like that, then you tend not to be willing to take any chances at all, and will only run ethanol free along with Blue Stabil.

If your only problem was not getting out of the marina, then you don't understand the really serious dangers that ethanol produced problems can cause. After all, its not for nothing, that the FAA has BANNED the use of ethanol in any aviation gas engines on airplanes. When it breaks down there, its the rocks, a mile down at terminal velocity.
 
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