Be Prepared

[XJWoody]

Since ethanol blends have become common, it can lead to fuel system problems (and top-end failures) in small engine equipment.

If one has ever left fuel too long in their mower/whacker/blower/saw etc, they likely know what I am getting at. The stuff magically changes from Dom Perignon to Boone's Farm (or worse.) The simplest "fix" is preventative: When you are done with the tool, drain the tank, start the engine, and let it idle itself to sleep. Don't rev the wee out of 2-stroke engines while doing this, as there is a risk of a lean-seizure, followed up with an unhappy trip to the New Piston store.

For stuff that sees routine use, mixing high-octane pump fuel with a good oil is all one needs to do... with that, I'd advise keeping it around for maybe 90 days MAX. Stihl Ultra synthetic mix-oil has stabilizer in it, but adding a dose of Sta-Bil (or eqivalent) can't hurt. Once I hit about 60 days, that junk gets dumped in the tank of one of our vehicles, and goes away. OTOH I only mix up a gallon or two at a time, unless I have a bunch of noise to make.

That doesn't help folks who rarely use their loud toys, or rely on a cache for use at some future date...

One solution is a product called 50fuel... it's a non-ethanol fuel, pre-mixed with synthetic oil at either 40:1 or 50:1. It is packaged in 1qt. cans, and should last a long time if unopened. Perfect for a reserve stash, but has a high cost. A similar product (Aspen) is sold in Europe. Even being pre-mixed with oil, it shouldn't cause any problems if run through 4-stroke equipment, such as a generator, mower, vehicle etc...

Another solution is 100LL "AVGAS" available at your local airport. This also has a long shelf life in a sealed container. One pilot guy on another board mentions using 9 year old avgas in a DC3, however the fuel was in sealed drums, and stored in a (very) cool/dry place. The drawbacks to 100LL are few: Availability - your local FBO may be reluctant to sell if you haven't got a plane out there looking thirsty. Moore County International is cool with small can sales though. Cost is an issue... it's roughly twice or more what pump high-octane sells for... Disposal is also an issue. Even with it's longer life, there may come a day when one decides it's not worth risking. Dumping this junk in the tank of momma's car "could" lead to a plugged catalytic converter. A quart or so in a full 15gl. tank, once in a blue moon, probably no worries, but it can and will lead to cat issues if one kept it up.

<Edit>: Some newer small engines come with catalytic converters... Husqvarna stuff has a green fuel cap that gives this away (also the mufflers are stamped "CAT'). Leaded fuel will not be good for the cat-mufflers on these...

Race fuel is another higher cost solution, and it's available in leaded or unleaded at various blends for different intended uses. It also has a high cost, and limited availability like 100LL.

A higher octane rating isn't really the savior here (unless one has done some things to the engine... raised compression ratio, changed timing events etc that requires it) More octane isn't better... Longer stability/useful life is.

The 'canned fuel' or 'expensive designer blends' seems like the best bet if a long shelf life is required... getting my head around really expensive fuel isn't easy or painless, but that's what it is. As I mentioned above, all my loud junk gets 92-93 octane pump unleaded, and premium-grade mix oil... but I date it, and feed it to the pigs once it clocks 60 days.