Small engines, alcohol-free gas, etc..

Any small engine guys here?

I just started using 91 octane, alcohol-free gasoline in my lawnmower, trimmer and snow blower. I've heard the ethanol stuff can really mess things up, and the content of ethanol in gasoline can be as high as 10%-15% (especially around me in Indiana). So no more burning corn syrup in my equipment.

Waste of time and money? I only use a few gallons each spring-fall so it's not a big deal to spend $2.90/gal instead of $2.20.

On a tangent, some of my equipment uses 50:1 fuel-oil mix. Is that OK to mix and store for maybe 4 months? Or should I be mixing it in smaller batches so I use it up within a month? I would like to avoid that hassle if possible.

To my knowledge, alcohol gas doesn't store as well as a non-alcahol blend.

Some of the antiques I run are said to run hotter with alcohol gas. The old heads were worried about cooking the cylinder heads, but those fears don't seem to have materialized.

Just drain the fuel at the end of the season, gummed up junk is a real pain to clean... especially in carbs. Seems like my engines always need a carb cleaning at the beginning of the season.

EDIT: Oh yeah, forgot to mention alcohol gas can mess up some carb floats. I had some carb floats that were mysteriously swelling. Turned out to be alcohol gas causing it.

Yeah, we have several small gasoline engines around and I wasn't aware that ethanol was a problem. Thanks for bringing that to my attention.

Last year was the first time I ran my mower dry. When I filled it this spring for the first time, ALL the gas flowed right out of the air filter. I'm guessing the carb float got stuck. It seemed to just fix itself after I waited a few minutes. In the past I always keep some stabilizer with 1/3 full gas tank and seemed to be OK.

If you have metal floats, good to go with alky gas.

If you have "some kind of plastic" floats, they may crack or swell. Hold a plastic float to your ear and shake it. If you hear liquid inside, it's float replacement time. In small engines, this is referred to as a "sunk float." It'll cause the carbs to send too much fuel or simply not cut off whatsoever and flood out the engine.

If the fuel **** is left in the on position in combination with a sunk float, gas will fill the engine, you'll lose air headspace, and you'll most likely break your seals.

Of course, some of the old stuff I work with has felt seals (aka MEGA LEAK seals.) Upside? They don't break. Downside? They don't actually seal.

Edit: In a non-premix engine, if your oil smells like gas then check the carbs and carb floats. Some carbs can be partially disassembled with fuel line still in place to see if the float needle is sealing and stopping gas flow. Spinning the needle in its seat can restore a lost float needle seal.

Heh. We're speaking my language, friends! I love the really old stuff, older the better.

Edit:

I'm guessing the carb float got stuck. It seemed to just fix itself after I waited a few minutes.

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Yeah, carbs with floats have a habit of doing this when the float chamber is dry, it'll only do it the first time. The float got sideways. Some carbs, you must remove the float chamber lid, then the float rights itself and it quits spewing fuel. This can be non-obvious if you're not watching for it. It would be a mysterious "cleared before isolation."

Edit 2:

On a tangent, some of my equipment uses 50:1 fuel-oil mix. Is that OK to mix and store for maybe 4 months?

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Should be fine, just as long as it doesn't turn to syrup. Alcohol gas doesn't store as well as non-alky. If just 4 months, then either way most likely.

Mark, any of your gear old enough to need lead additive? A cylinder head rebuild might or might not cure that need if so; valve seat and guide material, we've better stuff than in the 40s now. Metallurgy was junk back then.

A note for solid lifter engines:

ZDDP. It's an engine oil additive that the EPA is trying to get banned. Why? It fouls catalytic converters.

Why do us small engine guys care? ZDDP is there to keep your solid lifters and camshaft from failing. 0% ZDDP in the engine oil greatly increases the failure rate. Around 1800 parts per million is plenty. Too much is as bad as too little. This applies to tractors, speedboats, aircraft, and quite a lot of vehicles and equipment actually. For the most part, if it never had a cat, then ZDDP may be in order.

You can call the tech line for the oil company and ask about how much ZDDP is in there and whether or not it's right for your engine. An example, say in 40 weight, would be Valvoline VR1 racing oil. (1153 PPM ZDDP, it's still a decent amount.) It's not really that expensive. You can pay absolutely insane prices for ZDDP oil, often in excess of $30-$60 a quart! (I'm looking at you, Shell Aero and Spectro!) You can also get ZDDP on the side and add your own, but it's extremely tough to both 1) add the right amount and 2) mix it correctly before it goes in the engine. The engine operation will mix it on its own, but that's not a good way to start off.

https://en.wikipedia.org/wiki/Zinc_dithiophosphate

The main use of ZDDP is in anti-wear additives to lubricants such as greases, gear oils, and motor oils, which often contain less than 1% of this additive. It has been reported that zinc and phosphorus emissions may damage catalytic converters and standard formulations of lubricating oils for gasoline engines now have reduced amounts of the additive, though diesel engine oils remain at higher levels.[4]​ Crankcase oils with reduced ZDDP have been cited as causing damage to, or failure of, classic/collector car flat tappet camshafts and lifters which undergo very high boundary layer pressures and/or shear forces at their contact faces, and in other regions such as big-end/main bearings, and piston rings and pins. Roller camshafts are more commonly used to reduce camshaft lobe friction in modern engines. There are additives, such as STP(R) Oil Treatment, and some racing oils such as PurOl, Brad Penn and Valvoline VR-1, which are available in the retail market with the necessary amount of ZDDP for engines using increased valve spring pressures. The same ZDDP compounds serve also as corrosion inhibitors and antioxidants.

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This is a serious issue and can inflict much expensive damage on vulnerable engines. Roller lifter engines don't really care as much about ZDDP.

So no more burning corn syrup in my equipment.
Waste of time and money?

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Here's a couple of websites to help us find non-alcohol gas.
http://pure-gas.org/index.jsp
http://www.buyrealgas.com/

Non-alky gas is available at any marina, but they won't let you put it directly into a non-boat. Bring a can.

Mark,

I have two different chain gas stations close to me that sell alcohol free gasoline, both in regular and premium. Southern States co-op sells non-ethanol gas, and Royal sells both grades, regular and premium. In central Virginia, regular 10% ethanol blended gas runs $1.85 a gallon while non ethanol is running $2.20

The biggest problem with ethanol is that it is hygroscopic so it attracts moisture. The pot metal that most small engines use for their carburetors doesn't react well and the rubber hoses deteriorate when exposed to alcohol.

I'm old school when it comes to small engines. I mix my two stroke blend by the gallon. I purchase Mercury branded Quick Silver oil in gallons and keep a few small bottles of Stihl or Echo to use as measuring units. Prior to use the tank gets filled, the unit used then drained of fuel, and run dry.

My dad was a big fan of using Sta-Bil gas stabilizer. Come spring, every gas engine that he had the stuff in refused to start. The Pink Sta-Bil when mixed in gas and left for a few months would turn to jello.

more_vampires said:

Here's a couple of websites to help us find non-alcohol gas.
http://pure-gas.org/index.jsp
http://www.buyrealgas.com/

Non-alky gas is available at any marina, but they won't let you put it directly into a non-boat. Bring a can.

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The filling up in a marina is a no-no for a couple of reasons. Most marine gas sold falls under the agriculture clause and isn't taxed as road use.

Secondly, the only time I've ever purchased a load of fuel with water in it was a a large marina in a fishing town. After that, before I put any marine gas in my boat, I used one of the ethanol kits and tested the fuel. Kits are available on eBay for $11 or so. http://www.ebay.com/itm/Fuel-Tester...m1a07d885dc:m:m7A1NeZMKGmrTn42u-jMBQg&vxp=mtr

You're correct, of course. I probably shouldn't have advocated it. Nevermind, sorry!

What if we're just running a snow blower or weed trimmer? That's not road use. I don't feel it's fair to be taxed for road use if you're running a generator. Excellent point, though sir. By getting our generator fuel at the gas station, we're paying road tax.

Also, I've picked up a ton of water from a bad batch of gas at a regular gas station before. I junked the new fangled computer and sensors all up or something. Chevy ended up not being able to actually fix it! (Chevy SSR, horrific reliability problems on a good day)

NoNotAgain said:

The biggest problem with ethanol is that it is hygroscopic so it attracts moisture. The pot metal that most small engines use for their carburetors doesn't react well and the rubber hoses deteriorate when exposed to alcohol.

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Something I just found out about recently. For the longest time, I didn't think you could weld pot metal carbs as it would liquefy the whole thing once you got up to temperature. Apparently, there's stuff exactly for this:

https://muggyweld.com/pot-metal-repair/

Ethanol gas is horrible stuff... I use Startron to treat, and try to use within 6 months. EVERYTHING gets drained at the end of it's season. Sea Foam works nicely to un-gum smaller problems if fuel stays in too long...

more_vampires said:

You're correct, of course. I probably shouldn't have advocated it. Nevermind, sorry!

What if we're just running a snow blower or weed trimmer? That's not road use. I don't feel it's fair to be taxed for road use if you're running a generator. Excellent point, though sir. By getting our generator fuel at the gas station, we're paying road tax.

Also, I've picked up a ton of water from a bad batch of gas at a regular gas station before. I junked the new fangled computer and sensors all up or something. Chevy ended up not being able to actually fix it! (Chevy SSR, horrific reliability problems on a good day)

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There's a town in NOVA that looks like its lawn service international. The owners of the companies have numerous federal grass cutting contracts. The companies that don't have their own yard tanks usually purchase cutter gas on a separate ticket and file the paperwork to get the road use tax money back.

I've got a friend that produced bio-diesel. He had to get a license and has to file tax reports so that the MAN gets the road taxes.

A lot of people/companies when the cost of diesel gets high resort to using non-taxed fuel which is dyed. Pull into the scales, get your tank dipped. If they see any pink/red color, you've got big trouble.

I recently read an article that the EPA wanted to increase the ethanol percentage as the new vehicles already come equipped to run E-85 or higher blends. Since ethanol doesn't have the same BTU's of energy as gasoline, you lose mileage and performance. I've run the numbers using one of the EPA calculators and the math doesn't add up to require the higher ethanol blends. Cold weather performance on ethanol sucks.

Nothing but problems with small ethanol gas. Deteriorates and goes bad quickly. It ate out the rubber diaphragm in my push mower. In my tractors that only get used rarely the inside of the carbs looked like they had pond scum in them.

It's not really the EPA that wants to up the ethanol content, it's the corn lobbyists.

I remember when ethanol was first being added in my area, I was a tech at the time, and almost every Saab I serviced needed the fuel tank float replaced due to swelling from the alcohol.
Later I worked as a sales and service person on outdoor equipment, honda carbs did the worst with the ethanol, they had a seal in the fuel shutoff that would turn to gel and ruin the fuel system excluding the tank.

All of my two stroke engines get run dry for the season' send, the four strokes get fresh gas and oil. Each one starts with just a few revolutions at the start of the next season. I also use 89 octane or better, worth every penny.

When I worked at a mower shop, 85% of the problems were fuel related, most because of the ethanol. There is a change that occurs over time called phase separation. Good paper here on it.http://nationalpetroleum.net/Ethanol-Water-Phase-Separation-facts.pdf . Once this has happened then is allowed to sit, the ethanol then become very corrosive and causes much damage to carbs. We always told people once they were hit by this was to immediately treat your gas with stabilizer as soon as you get back from the gas station, and only buy as much as you will use in a 30-60 day period. If you are going to store it longer then double the dose of stabilizer. I always drain all my power equipment at the end of its respective season, but from seeing what happens to hundreds of machines I also remove the float bowl and wipe it clean, then reinstall to remove all doubt.....

So to answer your question, no it's not a waste of time, if non ethanol gas is readily available to you, use it.

FWIW, I've personally witnessed the aftermath of leaving ethanol fuel in a motorcycle carb for a long time...(several months, anyway if not longer). It turned the fuel to a thick, sticky goo the consistency of Vaseline...looked like a mess to have to clean out and I was glad I wasn't the one to have to do so.

I cut my lawn, probably for that last time this season, earlier this week. I ran a tank of 91 octane alcohol-free through it just for fun. Since the station that sells that is right next door to my work, I think I'll just keep on using that for peace of mind.

The best thing to use in small, two-cycle engines is the pre-mixed, ethanol-free fuel that you can get at any hardware store. I bought some this summer at Walmart for $5 a can. Apparently this fuel will keep for several years.

Something to remember about "running an engine out of fuel:" Though the float chamber of the carb will be "mostly empty," other parts of the carb may remain full of fuel. It depends on the carb design. Some keep the main jet, the idle jet, or both submerged in fuel even if the float chamber has been run to the point that no more fuel can be drawn.

It's this remaining fuel that can still cause problems by going to jelly or varnish.

The float needle of the carb float can corrode due to water attracted by alcohol gas, even with just a little bit in the bottom of the float chamber. Carbs with removable float bowls are a better design than unibody carbs, IMHO.