How does Sta-bil work ?

Status
Not open for further replies.
Joined
Dec 30, 2008
Messages
449
Location
wv
I've heard mention that Sta-bil floats on top of the fuel in the gas tank and carburetor float bowl.
This would presumably form a barrier between the fuel and the atmosphere where moisture absorbtion and fuel evaporation would otherwise take place.
IS THIS CORRECT?

Any and all input would be much appreciated.
 
Nope.. this is absolutely poppycock!

gas stabilisers work by stabilising otherwise unstable aromatic hydrocarbons, the one that would go bad fairly quickly.

That being said, however, even with stabiliser additives in gas, it can only last so long (maybe a year or so, depending on storage conditions, etc.) before it eventually goes sour.

Bottomline: fuel stabiliser basically slows down the process, not necessarily stopping it from decomposition entirely.

Q.
 
Can someone explain how Sta-bil does this?

Originally Posted By: Sta-bil
Removes water to prevent corrosion...


And what about water at the bottom of the tank?
 
Last edited:
Products like Sta-Bil are known as oxidation inhibitors. Their objective is to slow the degradation of the fuel molecule by keeping the fuel and oxygen from reacting. This type of protective stabiliser will generally last for up to two years depending on the environment the fuel is stored. Humid areas don't last nearly as long as arid environments due to moisture.

So think of the stabiliser as putting a protective barrier around the fuel molecule to keep it away from the air. Fuels stored in sealed metal containers will outlast fuels stored in naturally aspirated containers for the exact same reason.
 
Stuff like Stabil generally contains hindered phenolics that act as sacrificial molecules. That is, they react with oxygen before unsaturated materials in the gasoline can. BHT in food is an example of a hindered phenol. When all of this material is used up by reaction with oxygen, then the gasoline is vulnerable. Typically, additives use 2,5-dimethylhydroxy benzene as the antioxidant for fuels.
 
In my experience (my old '93 Yamaha FZR600) Sta-Bil will last at least two years. The machine ran fine with this two-year old treated fuel, but it got horrible fuel mileage. The +4.5 gallons lasted only 84 miles before hitting reserve.

I have no idea how it works, but it does.
 
thanks for the info and setting this issue straight guys...

So the Sta-bil actually completely mixes in with the fuel completely...
 
If Stabil is added to the container first, then filled with gas to agitate and mix the stabil through out the gas.

Just adding it to a tank of gas doesn't do much at all.
 
Originally Posted By: dwendt44
Just adding it to a tank of gas doesn't do much at all.

It does if you add the stabil first then fill your tank.
 
Originally Posted By: daman
Originally Posted By: dwendt44
Just adding it to a tank of gas doesn't do much at all.

It does if you add the stabil first then fill your tank.

confused.gif
Isn't that what he said?
Originally Posted By: dwendt44
If Stabil is added to the container first, then filled with gas to agitate and mix the stabil through out the gas.
 
Originally Posted By: flatlandtacoma
Originally Posted By: daman
Originally Posted By: dwendt44
Just adding it to a tank of gas doesn't do much at all.

It does if you add the stabil first then fill your tank.

confused.gif
Isn't that what he said?
Originally Posted By: dwendt44
If Stabil is added to the container first, then filled with gas to agitate and mix the stabil through out the gas.

Originally Posted By: dwendt44
If Stabil is added to the container first, then filled with gas to agitate and mix the stabil through out the gas.

Just adding it to a tank of gas doesn't do much at all.


i dont know did he?? he's talking about the container not the tank in your car.
 
Originally Posted By: daman
Originally Posted By: flatlandtacoma
Originally Posted By: daman
Originally Posted By: dwendt44
Just adding it to a tank of gas doesn't do much at all.

It does if you add the stabil first then fill your tank.

confused.gif
Isn't that what he said?
Originally Posted By: dwendt44
If Stabil is added to the container first, then filled with gas to agitate and mix the stabil through out the gas.

Originally Posted By: dwendt44
If Stabil is added to the container first, then filled with gas to agitate and mix the stabil through out the gas.

Just adding it to a tank of gas doesn't do much at all.


i dont know did he?? he's talking about the container not the tank in your car.

If you don't know, perhaps you should look at a dictionary :
tank [tangk] –noun 1. a large receptacle, container, or structure for holding a liquid or gas
 
Stabil is not some kind of oil that is resistant to mixing.

Pour it into fuel in a clear container. It mixes thoroughly and completely with no agitation.
 
Originally Posted By: flatlandtacoma
[If you don't know, perhaps you should look at a dictionary :
tank [tangk] –noun 1. a large receptacle, container, or structure for holding a liquid or gas


Dude your kidding me right? thats some funny [censored] right there^^
 
One thing to consider is don't add it to an empty tank of your equipment and then add the gas.

Recently, I drained the gas in my generator and poured that gas into the kids car. (They are always looking for "free" gas!) I put enough Stabil in the tank for 5 gallons of gas, added the gas and the generator wouldn't start.

Seems I filled the carb with stabil. I closed the fuel shutoff, drained the carb, putting the contents back into the tank with a little more stable for good measure, and it would run again.

So I would caution that anything gravity fed should be pre-mixed prior to the adding to an empty tank. Adding the stabil first lead to a no-start condition as is went right to the carb.

I know, I could have closed the valve as well. However, it still would have filled the line and not mixed as well.

Add it to a gas can or a full tank of fuel. But don't add it to an empty gravity fed tank.
 
Originally Posted By: FowVay

So think of the stabiliser as putting a protective barrier around the fuel molecule to keep it away from the air. Fuels stored in sealed metal containers will outlast fuels stored in naturally aspirated containers for the exact same reason.


Correct. When storing for an extended time, use the Stabil and TOP OFF YOUR TANK! This almost eliminates air from reacting with your gas. In fact, I overfill during storage until I see gas literally one inch from spilling out the filler hole. Has worked great for years!
 
I don't know about y'all but my fuel is subject to energy thus it's a liquid with a proclivity toward colloidal dispersion and being that it is not attached to a stationary engine it tends to move around somewhat shaken and stirring.

I would even speculate the there may even be convection doing its b'ness.
 
Status
Not open for further replies.
Back
Top