shelf life: premium vs reg?

   / shelf life: premium vs reg? #1  

big bubba

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arkansas
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have a small landscape business plus a rural farm so i run a lot of high dollar 2 & 4 stroke engines. use stabyl & ethanol treatment (this is not about what additive to use). have been told that premium gas in general will outlast regular in shelf life. if so, is this difference negligible if additives are used? any other reason to use it for small engines?.....anyone out there use premium over regular for this application & why? thx in advance
 
   / shelf life: premium vs reg? #2  
Short answer, no! Now if you can get non ethanol gas that's what I would run. I can't get non ethanol but do use 100LL aviation fuel in my 2 stroke stuff.

Chris
 
   / shelf life: premium vs reg? #3  
Non-ethanol 91 octane and treated with Stabil is the way to go.I used to buy at the marinas but now the local stations carry it.I also use Startron in my boat and it sits all winter and starts right up in spring.
 
   / shelf life: premium vs reg? #4  
The octane rating doesn't change the storage life of gasoline. Like dp said, your best bet is pure gasoline if you can get it. The issue with ethanol blends, from the facet of storage, is that ethanol is water soluble thus absorbing water if given the opportunity.

I use 87 octane ethanol for my wood splitter and all of my two cycle equipment. I add one ounce of Seafoam to my 50:1 mixture for the two cycle equipment which solved the hard-start problems I had at one time.
 
   / shelf life: premium vs reg? #5  
I only have two 2-stroke engines; a Stihl string trimmer and a Mantis tiller. The manual for the Mantis recommends "branded" 89 octane gasoline and the Stihl 87 octane. Both call for 50/1 mix ratio. So I use 89 octane with Stabil and with Stihl's Ultra (synthetic) oil in both. Stabil claims to keep gasoline, including ethanol, fresh for 12 months, and while I don't see it anymore on their bottles or website, I believe they used to say to use a double dose for longer storage. Anyway, I don't use any other additives, but do use a double dose of Stabil all the time. I also add Stabil to the 89 octane gasoline for my ZTR mower with a Kohler engine.
 
   / shelf life: premium vs reg? #6  
I think the key is to keep rotating the stored gasoline (regardless of octane) such that it is used in less than 3-4 months. My stored gas sits in a shed in 5 or 2 1/2 gallon containers using the red Stabil ( 1 oz in 2 1/2 gallons). I usually have 10-15 gallons on hand, depending on the season. Being retired with not much else to do, I use up any older gas in my truck so as to keep things fresh as possible. When making fresh 1:50 for the Stihl 2 stroke equipment, their mix has a stable product in it as I understand. But using older gas with Stabil doesn't seem to interfere with two stoke performance. BTW, I quit using up old two stroke mixes in my truck. My local mechanic said that it could mess up the O2 sensors. Thus I try to make smaller amounts, and use it up in the saws, blower, brush cutter etc. cheers, Mike
 
   / shelf life: premium vs reg? #7  
I had been told for several years that gas shelf life was short. This Fall I had some chainsaw gas that was at most 2 months old. My saws simply would not run on it. You could get them started but they wouldn't generate any power. Mixed up new gas and they were fine. I Stabil all my 4 stroke engines that are seasonal use.
 
   / shelf life: premium vs reg? #8  
I had been told for several years that gas shelf life was short. This Fall I had some chainsaw gas that was at most 2 months old. My saws simply would not run on it. You could get them started but they wouldn't generate any power. Mixed up new gas and they were fine. I Stabil all my 4 stroke engines that are seasonal use.
I have the same issue with my Husky chainsaw. It might crank but wont idle and has no power on old gas. My Craftsman Zero turn wont even start on gas left in from last season, put in fresh gas and it started right up. I still put old gas in my truck including any left over 2 cycle oil (usually less than 1 gallon as that is the max I mix up). I don't think adding that small amount to a 25 gallon tank is going to hurt any sensor, at least not in the last 5 years it hasn't. Recently I put some 2 cycle in a 4 cycle lawnmower and it ran and started good on the 40:1 mixed gas with no smoke either. The motor has been setting for almost 4 years without even being turned over. Started right up, ran for about 5 minutes and stopped it , changed oil and used it to pick up and shred some leaves without any issue. The old oil did look like it has some aluminum dust in it so I did wear some on the cylinders it appears.
On my riding lawnmowers, I try to run them dry or nearly so and them put in a generous amount of STABIL for over-wintering, then fill with fresh gas in the spring. That's seems to work for them. Chainsaws, weedeaters and push lawnmower engines, I drain completely and pump the primer bulb a few times to push all the gas out. I have a 13 year old powerwasher that I have done that with every time I use it and it still cranks on the second pull (one on full choke then move to run and it fires up) Some folks claim that gasket dry out when doing that , but I haven't found this to be the case.
 
   / shelf life: premium vs reg? #9  
My local Shell station now sells Marine Grade gasoline. Anyone know what this consists of. It is about a dollar per gallon higher than regular. 2 other closer stations sell PURE gas and prices run from 20 to 40 cents per gallon more. I try to use these in all my small engines and put in 89 octane. My chainsaws / weedeaters run better on it but I cant tell any difference in the riding lawnmowers. During summer when I have high usage, I go back to regular ethanol blended fuel for the lawnmowers as it doesn't set more than 2 weeks without using it up.
 
   / shelf life: premium vs reg? #10  
My local Shell station now sells Marine Grade gasoline. Anyone know what this consists of. It is about a dollar per gallon higher than regular. 2 other closer stations sell PURE gas and prices run from 20 to 40 cents per gallon more. I try to use these in all my small engines and put in 89 octane. My chainsaws / weedeaters run better on it but I cant tell any difference in the riding lawnmowers. During summer when I have high usage, I go back to regular ethanol blended fuel for the lawnmowers as it doesn't set more than 2 weeks without using it up.

As I stated before;our marine gas is 91 octane non-ethanol......stores very well.I also add marine stabil and Startron.My boat,mower,trimmers ect. sit idle for eight months with no problems.I fill the tanks and run for about five minutes.I believe the Stilh oil has Stabil added to it,my two cycles sit for long periods with no problems at all.
 
 
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