Easy.. Test Gas for Ethanol

Cool. Shoulda did that with the 5 gallons of junk I got a few months back.

 

Tried this test on the Sunoco Premium 93 I picked up in Michigan yesterday. There were none of the usual "Contains Ethanol" signs on the pumps and when I asked the attendant if their gas contained Ethanol? She replied "What's Ethanol? Never heard of it and I'm sure it's not in our gas...."

Looks like the wife's car is getting a 5 Gal top up of Premium

 

Wow!
The generator has some old gas in it and i'll try out the water bottle trick later.

 

I tried this because I had a saw that was just not running well. I dumped what was in the saw and the remainder of my jug in a bottle with water.

After settling the water is higher than the line. Does this mean there was water in my mix or the ethonal separated from the gas and blended with the water?

 

Not sure but looking at my bottle above I'm thinking that if the water portion of the water/gas mix was clear it's likely just water in the fuel but if it was cloudy like above, I'd be leaning towards the Ethanol fuel blend.

 

Just did the gas settling thing with the gen gas but didn't add water Paul. Gonna give it a half hour and see whats what. Looks like old gas now.

 

I'm not sure that will show much. I added water to the red/pink line then added the gas and shook it up before leaving it to settle. Let me know how you make out

 

Didn't do nothing! and I did the other test wrong as I didn't mark the bottle first. The hell with it I'm going out back start a fire and split wood!!!

 

Here's a question. If you live in an area where you can not get E-free gas, Can you do this test above and then siphon off the top portion of the gas, essentially making your own E-free gas? Theoretically, the ethanol has been removed from the gas and is now mixed with the water.

 

Sure you can. The problem is that the ethanol is used to increase the octane of your fuel. If you remove it the octane will drop significantly because the ethanol will not longer be present in anywhere near the former concentration.

 

I was wondering the same thing.

Do you know a percentage?

 

+1 Ethanol is a cheap octane enhancement to gas. Also, it is hygroscopic, loves attracting water, which is why you will see phase separation in vented gas tanks.

 

Okay, I understand that, but wouldn't a lower octane E-free fuel still be better than a high octane fuel with ethanol in small engines?

 

High compression and timing curves of our modern chainsaws require higher octane to prevent detonation and flame front collisions. Pre-ignition and detonation are a quick way to destroy a piston/cylinder.

 

Ethanol is rated at 113 octane, when you have a E10 blend refiners get away with running a lower octane gas mixed with Ethanol. Take away the ethanol in the blend or enough water is concentrated in the gas your net over all octane number has dropped. That was what I was referring to from above.

"Guidelines for using E10 gasoline in STIHL power equipment:
If the proper precautions are taken, gasoline containing a 10% quantity of ethanol can safely be used in your STIHL products.
Use a minimum of 89 octane gasoline and always use fresh fuel. Only buy enough gasoline that you can easily use up within a two-month period"

Further, because of the oxygenates, switching between E10 and Regular gas, has different adjustments when tuning a carburetor.

Lastly, I have found buying Non-oxygenated gas can be problematic. Some gas stations don't sell enough of it and buy whenever it is needed. In Minnesota that can be a problem because of 4 seasonal formula change overs, (Reid Vapor Pressure). Gas has to move to vapor easier in winter than summer. I've had that happen where you are borderline vapor locking in the middle of summer because the gas I bought was a winter blend that was not changed over. Drained out the gas and ran E10 87 octane and problem solved.
Was not fun, had to drain and retune 9 work saws on a big job.

Ok, I am done rambling.

 

I used to separate out the alcohol and water, but have stopped making the "witches brew". I was noticing some water allways traveled with the gas after trying to separate things out. I tried removing the ugly cloudy mix from the bottom, and tried siphoning off the good gas from the top. If you can overcome the few drops that migrate with the separated out gas, then its ok to run. For some reason I noticed some equipment didn't like to adjust smoothe with the separated out stuff. Maybe it was some water droplets getting around, maybe it was something else. I did notice that my engines ran better with 110LL, and they run even better with the VP SEF.

The percentage is about 3% octane drop. If you start with 92 and separate out the ethanol with water, you drop down to 89.

 

Yeah, there's some of that going around. It's called ignorance.

One thing people don't seem to realize is that if a station is a chain, like bp, Mobil, Conoco, marathon etc, if a tanker truck pulls up to fill their tanks, even if its e10 and the station claims that they don't sell ethanol added fuel the station has to take it. They have no choice. Now, what's worse is if they still claim it's ethanol free, and it in fact does contain ethanol.

It used to be that there were stations that you could reliably get 87 or 89 in ethanol free in my state but times are changing, and finding e free premium around here is pretty rare. It used to be only a few counties in the SE corner of our state had e10. Fast forward over 20 years, and the fuel companies don't like to make so many mixtures and try to sort it out logistically. So, now it's all e10, doesn't matter what grade.