use of fuel additives or NOT ?

HT32BSX115

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That being said, phase separation is pretty much an overblown problem and if you get your fuel from a reliable source and/or make sure you gas cap is on tight you would never have an issue.

Yes you are quite right............... it is very overblown.................... Most marketers of fuel "driers" for marine use talk more about condensation and how great their product is at taking "care" of that source of water. Fact is........problematic water intrusion is not from condensation (even though many think or claim it is)

Water intrusion is usually from fuel contamination from the source (retail or wholesale distributors) or from water leaking in through poorly sealed fill caps and vents etc. This produces far more water in the tank that could possibly occur due to condensation or that be mitigated by dumping in another alcohol. [SEE: http://www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm ]

As always, unfortunately, there simply IS NO "Mechanic-In-A-Can"
 

Gold Eagle Co

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The source of where you purchase your gasoline can certainly contribute to causing phase separation. Stations with low turnover and low quality gas can cause their fair share of headaches. Another major cause, though, is storing gas in a container, tank, etc, that is not full. This can allow condensation to form. The more room for condensation, the higher the probability of phase separation occurring as that water gathers.

Phase separation does not occur simply because ethanol blended gas sits for an extended period of time (which is a common misconception). You need the right amount of water (as little as 4 teaspoons of water per gallon of gas) to be absorbed in order for this issue to occur. Once it has occurred, you must drain the tank. No additive in a reasonable amount will help fix phase separation.

Have a great day!
 

bruceb58

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5 gallon gas can completely empty at 68 degress with100% humidity will have 0.33 ounces of water in it.Not really an issue.
 

airshot

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i am being told by two different marine repair shops .. #1 says, " use HEET additive to help reduce water from fuel tank problems" # 2 says "ABSOLUTELY NOT-NEVER USE THE ADDITIVE... THE VOLVO PENTA fuel filter system is perfect for capturing the water and you'll only make it worse by using an additive..." I respect both of these guys, which one is right... both are adamant that the other is wrong ( #2 used to work for #1 )

I would highly recommend trying an additive and see if you can tell the difference. Brand name additives will NOT cause any harm to your engine or fuel system. Depending on where you get your fuel will have a much bigger difference than any thing else. In my case any fuel I buy within 20 miles has the same issues as they run their storage tanks to low so.....yes additives do work for me. When I stop using them I can tell the difference immediately, so I keep using them as cost is really minimal for the added performance and smoothness I get. If I saw no difference then I would not use them but in my case I do. Please don't bash those who do use them and gain a benefit from them and do not bash the mfg of such products as they are trying to help those who do have issues. While lack of proper maintenance may well be the main problem in many cases, some of us live in areas where quality fuels can be difficult to come by, no matter how well we maintain our engines.
 

45Auto

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bruceb58 said:
5 gallon gas can completely empty at 68 degress with100% humidity will have 0.33 ounces of water in it.Not really an issue

.33 ounces/day and not using your boat for 6 months means 1/2 gallon of water in your 5 gallon tank.

I've towed in several boats where that was a MAJOR issue.
 

GA_Boater

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.33 ounces/day and not using your boat for 6 months means 1/2 gallon of water in your 5 gallon tank.

I've towed in several boats where that was a MAJOR issue.

Where is all this water coming from?
 

bruceb58

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.33 ounces/day and not using your boat for 6 months means 1/2 gallon of water in your 5 gallon tank.

I've towed in several boats where that was a MAJOR issue.
That's if you open the cap of the tank/can every day and every bit of water condenses out(pretty much impossible unless the temp drops 50 degrees) and then get every bit of air gets replaced when the temp rose and there was 100% humidity again. Not a likely occurrence unless you get a fan and force it to happen.

If you towed in a boat that has water in the fuel, how would you know it was from condensation and not from the fuel delivery or bad fuel cap?

45Auto...haven't seen you on here in ages. Missed your good posts!
 
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keith2k455

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Jul 23, 2012
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558
Additives will dilute the octane of your fuel. By how much, it depends. I used to run stabil through every tank, but once I started looking into tuning a turbo car I stopped. I also realized that my boat, lawn mower, leaf blower ran better when I stopped treating everything. I do run stabil for storage.
 

Gold Eagle Co

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Additives will dilute the octane of your fuel. By how much, it depends. I used to run stabil through every tank, but once I started looking into tuning a turbo car I stopped. I also realized that my boat, lawn mower, leaf blower ran better when I stopped treating everything. I do run stabil for storage.

STA-BIL? is petroleum based and blends with the fuel, most of what you see is carrier petroleum based chemical. With a treat rate of 1oz to 10 gallons it will not reduce your octane a measurable amount, The percentage of STA-BIL? to fuel is too small to make a difference in that regard.

If you have had good luck storing/running your marine engine without a fuel additive that is great. Some people do not have as good of luck which is why many OEM manufacturers recommend STA-BIL? or their branded fuel stabilizer when storing your boat.

Have a great day!!
 

HT32BSX115

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STA-BIL? is petroleum based and blends with the fuel, most of what you see is carrier petroleum based chemical. With a treat rate of 1oz to 10 gallons it will not reduce your octane a measurable amount,

Just about any addition (in typical "additive" levels) of an alcohol based "additive" does NOT decrease octane number (it can actually INCREASE octane number slightly) As claimed by SUNOCO in the following article http://www.racegas.com/article/11

A better description of the effects and history the use of alcohols as a major component of gasoline can be viewed here: http://www.ext.colostate.edu/Pubs/farmmgt/05010.html

In general, the effect of "over-the-counter" (NON-octane-boost) fuel additives on octane is negligible.

Even the retail "octane-booster" additives don't increase octane a huge amount (unless you believe the people that sell them!!) which is why real racers use "RACE" gas over octane "boost" additives.
 

keith2k455

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Well, all I know is untreated gas runs better than treated. Be it Briggs, Harley, Honda, Husqvarna, gm or merc in my garage. So either the definition of"noticeable"is up for debate or these Studies Are done in too much of an isolated lab environment to mean anything on the real world.
 

HT32BSX115

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Well, all I know is untreated gas runs better than treated. Be it Briggs, Harley, Honda, Husqvarna, gm or merc in my garage. So either the definition of"noticeable"is up for debate or these Studies Are done in too much of an isolated lab environment to mean anything on the real world.

I suppose................................ I guess I'll still stand by my previous statement in post #7........
If using additional "stuff" in the fuel or oil makes you feel good, nothing anyone says here or anywhere else will change that!

OMG! :facepalm: it's getting REALLY "DEEP" when I start quoting myself!!:frusty:
 

WIMUSKY

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Well, all I know is untreated gas runs better than treated.

Never heard that one either. So that's a first too.......

Couldn't double quote for some reason. Maybe because I was quoting the same member....
 
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