Ok, so which gasoline do you guys use?

[primedoc]

My first fill up was a real pain. I drove to every gas station (literally) in town to find the one station that had ethanol free gas and of course it was 87 octane. I have been told (not sure if the guy knew what he was talking about) that you are ok to use 10% ethanol as long as you do not STORE the boat with ethanol gas in it. Finding ethanol free gas here is a real pain in the ass and in every case it's in one of those pumps over to the side of the gas station away from all of the regular pumps where people fill their cars. With a rig that is 45 feet in length overall it can be difficult to get into many of those little / awkward spots that they put the ethanol free pumps as well. I assume that these pumps see little use and are used mostly by folks getting gas for their 2 cycle leaf blowers and weedeaters. I'm thinking that with that little volume going through those pumps there is a much greater likelihood that there might be water or worse in fuel from those types of pumps. What are your thoughts and what do you guys run, ethanol free 87 octane or something else?

We have enough engineers so hopefully there is a chemical engineer who will weigh in as well.

 

[Speedling]

You are fine with 87 octane 10% ethanol.
If you really want ethanol free, try marinas.

 

[biglar155]

I run ethanol-free but there's a handy gas-station about 5 miles from my house (and on the way to the lake) that carries it. They only carry ethanol-free in premium though. I wish they had it in the 87 octane variety 'cause it would save me a few bucks. There is absolutely no need to run premium gas in our boats, it's just my only choice if I want no ethanol. And I'm a firm believer in staying the heck away from ethanol.

Just my 2 cents.

 

[primedoc]

You are fine with 87 octane 10% ethanol.
If you really want ethanol free, try marinas.

Why 87 and not 89? No increase in performance or do the engines run hotter with the 89? I haven't read that part of the owner's manual yet - to busy reading here. LOL
I have a Yamaha Rhino and they recommend 87 in it due to running hotter without any performance benefit with 89.

 

[Speedling]

Engine is rated and built for 87 octane with 10% ethenol. You will gain nothing by running 89 other than maybe losing a little power. You may actually gain a little power by running ethenol free. We're talking like 1 hp really either way.
So there really is no benefit. Don't pay more than you have to.

 

[4x15mph]

I wanted to find ethanol free as well and I came across this app for the iphone, android, ipad - http://pure-gas.org/

The app helped me to find out that there is not any ethanol free anywhere near me. For now, I will treat the gas with stabil

 

[Troy]

If you are concerned about storing your boat with ethanol fuel then be sure to use a fuel stabilizer that is made for our boats like Sta Bil
https://jetboaters.net/threads/stabil-or-ringfree.799/#post-10376

 

[SCSTWG]

Most on this site suggest using Marine Stabil in your gas regardless if you have ethanol or not.

 

[Ronnie]

Nothing technical about my response, I use whatever Costco carries because it is cheaper and convenient (there are plenty of them, one close to my house and access is great, lots of pumps, high overhangs and long hoses so you can pull up to any pump regardless of which side the gas cap is on). When I do store the boat in the off season I simply treat the gas in the tank with marine stabil. If I was concerned about the ethanol content i might always treat the gas with stabil instead of try and find a station that had ethanol free fuel. As for getting bad fuel, the source has been marinas in all of the stories I've ever read about.

 

[Lspeedss]

@primedoc 87 with 10% ethanol works fine in our boats and 87 is recomended,it is a big concern for marine use btw for two reasons. The obvious water seperation and in craft that have metal tanks it can be disastrous as it eats away the tank.
Fear of the water seperation can be fixed by adding high pressure rates filter seperators( done years ago). Recommend this.. the other issue is of no concern as our fuel tanks are plastic..
I do fill up at the marina most of the summer and they have only 89 non ethanol..no issues so far other than the empty wallet. I fill and add marine stabil when I winterize. No problems any spring so far...cranks right up.

 

[watsino]

I'm thinking that with that little volume going through those pumps there is a much greater likelihood that there might be water or worse in fuel from those types of pumps. What are your thoughts and what do you guys run, ethanol free 87 octane or something else?

We have enough engineers so hopefully there is a chemical engineer who will weigh in as well.

The problem with ethanol is it acts like a sponge for water. If E10 comes in contact with enough water (>0.5%) a phase separation can occur where the ethanol will drop out with the water to the bottom of your tank. This is bad for 2 reasons;
1) It will rob octane from the gasoline (ethanol has an octane of ~100 R+M/2). The typical boost 10% ethanol gives your gasoline is 2-4 octane points
2) It creates a layer of water/ethanol mixture in the bottom of your tank that will eventually hit your engine. This is bad because water has a vaporization expansion factor ~10 times that of gasoline and can wreck an engine if there is too much.

As for your pump question; most retailers should have a float level switch on the bottom of their tanks to detect the water level. The suction of the gasoline pump sits above the bottom of the tank for this reason. Non-ethanol fuel will separate from water much easier and can be drawn off without the ill effects. However, if it is not drawn off it can still have the issue #2 described above. I have heard of retailers having these switches broken, or ignoring the alarm, but that is the small minority of stations.

I run ethanol free because for the extra 0.20 per gallon it makes me sleep better at night if I leave 1/2 tank in my boat for extended periods of time. I fill up a 5 gallon can on my way home from work as I also do not enjoy taking my boat to gas stations. If I do need a full fill up for a long day on the water I would do it right before I go out on the water and therefore wouldn't care as much about the E-10. If you are burning pretty much the whole tank within a week or two E-10 should not pose a problem.

If you want to use E-10 exclusively, I would recommend a marine fuel stabilizer as it will provide some protection against the phase separation. I even use a smaller dose of marine grade stabilizer in my non-ethanol fuel. Something about operating an engine on the water makes me extra conservative.

Even more into the minutia; a higher octane gasoline (91/89 vs 87) will run hotter because it has more BTU/gal (we typically use denser material to make the higher octane stuff). Ethanol actually burns a lot cooler in engines because it has much lower BTU/gal. Ethanol is an oxygenate as well so it provides for more complete combustion (less VOC out the tailpipe). Although, most newer engines have sensors that would know if it wasn't getting enough air and would compensate for it. Too bad MTBE gets into the groundwater and causes all types of badness, because otherwise it was a much better oxygenate as it is not hydrophillic and does not require food source material...

B.S. Chemical Engineering Bucknell University
8 years in the Refining business

 

[beachbum]

Gas related question ... I have two 5 Gallon portable gas containers that I would mix oil and gas in for my 2 stroke outboard (50 : 1). Now that they are empty and the 2 stroke is sold... do you think I can fill these up and use them for filling the SX 190? or ... bite it and buy new.

 

[Zeus2013]

Gas related question ... I have two 5 Gallon portable gas containers that I would mix oil and gas in for my 2 stroke outboard (50 : 1). Now that they are empty and the 2 stroke is sold... do you think I can fill these up and use them for filling the SX 190? or ... bite it and buy new.

probably just need to get the oil out.

 

[motorboater]

Gas related question ... I have two 5 Gallon portable gas containers that I would mix oil and gas in for my 2 stroke outboard (50 : 1). Now that they are empty and the 2 stroke is sold... do you think I can fill these up and use them for filling the SX 190? or ... bite it and buy new.

Yup you'll be fine. No need to replace them.

 

[watsino]

I can think of 2 things that would help minimize the effect of using the containers that had 2 stroke in them.
A) use a fuel system cleaner with or shortly after the 1st fill with the cans. I put some links below, but you should be able to find these in your local store for ~$5 or less.
http://www.amazon.com/STP-78575-Con..._3?s=automotive&ie=UTF8&qid=1397230616&sr=1-3
http://www.amazon.com/Chevron-65740..._4?s=automotive&ie=UTF8&qid=1397230616&sr=1-4
B) flush the cans with ~1 gal of fuel and use it in a 'more forgiving' engine like a lawnmower. I have a 4 stroke lawnmower that I would use as my 'sacrificial' motor for the very small amount of deposits you will see from any remaining oil there might be. The 1 gallon flush will lower the effective oil mix ratio from 1,000:1 to 20,000:1 after you flush it with 1 gallon of fuel (assuming 95% removal of the oil; some will stick to the walls). The volumetric ounces of oil remaining would be 0.55 vs. 0.03 oz before/after the flush and 5 gallon fill.

 

[cane.mba]

I run Stabil in every tank ethanol or not. Plus every third or fourth tank I'll add an extra ounce or so, since it also acts as a fuel system cleaner. At least that's what the back of the bottle said. What can I say, I get bored pumping 50 Gallons of gas in the boat and I'd rather not watch the $s increasing...

 

[Wayloncle]

Gas related question ... I have two 5 Gallon portable gas containers that I would mix oil and gas in for my 2 stroke outboard (50 : 1). Now that they are empty and the 2 stroke is sold... do you think I can fill these up and use them for filling the SX 190? or ... bite it and buy new.

I'd fill the can up and pour it in my boat or truck, that little bitty bit of oil that will be left over mixed in with 20 or 40 gallons of gas will be nothing.

 

[motorboater]

Transporters will load their tanks with maybe a diesel fuel on one trip, then gasoline of various grades on the next trip and so on. There is some residual product left in the tanker's lines but it doesnt matter due to the volume of delivered product. I view this as the same thing. I wouldnt hesitate for a second to use the same empty can for my boat.

 

[Britboater]

I'd imagine the out of the way pump you mentioned would be used by classic car enthusiasts too, not just leaf blowers etc.

 

[primedoc]

The problem with ethanol is it acts like a sponge for water. If E10 comes in contact with enough water (>0.5%) a phase separation can occur where the ethanol will drop out with the water to the bottom of your tank. This is bad for 2 reasons;
1) It will rob octane from the gasoline (ethanol has an octane of ~100 R+M/2). The typical boost 10% ethanol gives your gasoline is 2-4 octane points
2) It creates a layer of water/ethanol mixture in the bottom of your tank that will eventually hit your engine. This is bad because water has a vaporization expansion factor ~10 times that of gasoline and can wreck an engine if there is too much.

As for your pump question; most retailers should have a float level switch on the bottom of their tanks to detect the water level. The suction of the gasoline pump sits above the bottom of the tank for this reason. Non-ethanol fuel will separate from water much easier and can be drawn off without the ill effects. However, if it is not drawn off it can still have the issue #2 described above. I have heard of retailers having these switches broken, or ignoring the alarm, but that is the small minority of stations.

I run ethanol free because for the extra 0.20 per gallon it makes me sleep better at night if I leave 1/2 tank in my boat for extended periods of time. I fill up a 5 gallon can on my way home from work as I also do not enjoy taking my boat to gas stations. If I do need a full fill up for a long day on the water I would do it right before I go out on the water and therefore wouldn't care as much about the E-10. If you are burning pretty much the whole tank within a week or two E-10 should not pose a problem.

If you want to use E-10 exclusively, I would recommend a marine fuel stabilizer as it will provide some protection against the phase separation. I even use a smaller dose of marine grade stabilizer in my non-ethanol fuel. Something about operating an engine on the water makes me extra conservative.

Even more into the minutia; a higher octane gasoline (91/89 vs 87) will run hotter because it has more BTU/gal (we typically use denser material to make the higher octane stuff). Ethanol actually burns a lot cooler in engines because it has much lower BTU/gal. Ethanol is an oxygenate as well so it provides for more complete combustion (less VOC out the tailpipe). Although, most newer engines have sensors that would know if it wasn't getting enough air and would compensate for it. Too bad MTBE gets into the groundwater and causes all types of badness, because otherwise it was a much better oxygenate as it is not hydrophillic and does not require food source material...

B.S. Chemical Engineering Bucknell University
8 years in the Refining business

Now there's the answer!! I knew we had to have one of you guys on this board with all of the tech / engineer members we have.