Your thouhts on fuel please

[Bret4207]

Okay, so we've all seen the fuel oil mix that if left in the tank turns to maple syrup and gums up our carbs. OTH, I've seen lots of recent mix that didn't do that. For instance, customer brought in a little bargain store Poulan 4218 that was so gummed I think I'm going to ahve to get a new carb for it. Conversely (first time I've ever used that word!) yesterday I dragged out my Sachs 133 that I hadn't run in a couple years, poured a little gas in the carb and it started and ran fine with no sign of gumming. The Sachs mix was Wally World mix oil and gas from the corner store. The Poulan was Poulan oil and gas from the same corner store.

My question is- what is it that makes some mix turn to gum in few weeks and others seemingly stay good for years even? All this takes place in extreme northern NY where we've had 10% alcohol blended fuel for several years.

 

[Bret4207]

No thoughts or opinions?

 

[Fish]

What they sell as "gasoline" these days is a complex mix of chemicals that changes constantly, depending on time of year, and likely with whatever is cheapest, current legislation, ethanol lobby, etc.

So it would be a hard topic even to attempt to discuss here.....

But that never stopped the guys before..........

 

[cajunhillbilly]

I wish I could answer your questions, but I can't. Their is a billion and one threads on gas and mix opinions. All I run is premium to super no E10 with opti2 or better oil in all my 2 strokes. If I could get still leaded premium gas I would. Corn Whiskey is only good for drinking.

 

[tbow388]

bad gas

I would think it has something to do with the Ethanol.

I have had that problem before with ethanol. Once I started using E-free gas I havent seen that problem any more.

 

[Da83moon]

Could the storage temp. have anything to do with it? Maybe if you had stored in a basement or a cooler surrounding and he had stored his in a hot area, the chemical reactions created some type of evaporation.

 

[genesis5521]

Ethanol is the problem. It attracts moisture. Around me, all 87 and 89 octane gas has it. But a very few gas stations have 91/93 octane with no ethanol. This is all I ever use and my gas seems to last forever and doesn't gum things up. If I'm not gonna be using my chain saw for awhile, I dump the gas in it and run it till it dies. My saws always start easily and quickly. Oh, to every gallon of gas I mix up, I always add some kind of fuel stabilizer which I get from my Stihl dealer. That probably helps to.

Don <><

 

[user 64030]

Well since the OP said ethonal is in both fuels, and only one went gummy I am not sure it is at fault (completly). The biggest change you see in gas is summer/winter blends. Here in KY from Memorial day - Labor day we have a different blend. Also if you are in the great liberal city of Louisville (insert sarcasm please) they run the RFG gas even thought hey do not. So time of year and geograpy change the gas you can get at the pump....

dw

 

[mtfallsmikey]

Well since the OP said ethonal is in both fuels, and only one went gummy I am not sure it is at fault (completly). The biggest change you see in gas is summer/winter blends. Here in KY from Memorial day - Labor day we have a different blend. Also if you are in the great liberal city of Louisville (insert sarcasm please) they run the RFG gas even thought hey do not. So time of year and geograpy change the gas you can get at the pump....

dw

Oxygenated gas, used to be just for only urban areas mandated for winter use. Best thing to do IMO is use 93 octane Shell/BP, and Stihl HP Ultra, has stabilizer in it.

 

[a. palmer jr.]

I did a web search and found a station 15 miles from me that sells ethanol free gas. I'm gonna get over there pretty soon and see if it's true..I'm taking my gas cans with me just in case. Even if ethanol isn't the problem, it's part of the problem.

 

[stihlrookie]

I run 92/93 octane non-ethanol gas in my Stihls. HP Ultra for mix and some fuel stabilizer in the winter. I don't use added stabilzer in the summer, go through gallons of mixed fuel frequently enough to not worry about it. I always keep the tanks full to the top. I heard leaving them empty or anything other than full, condensation could form inside the tank. My saw may sit for a month without running in the winter and my trimmers and blowers sit for up to 6 months without running. I keep the tanks full and stabilizer in the fuel and don't seem to have any problems. My storage building is unheated and, lets see, it was 16 degrees this morning.

 

[flyboy553]

My old Craftsman 42cc sat for over a year with half a tank of gas in it, and it fired right up, as did my 55 Rancher which sat for 4 months. They ran just fine, no issues at all. I do use Husky's synthetic oil, and that is probly what saves them from gumming, I don't know.

I think some get a little too hyped up about some things. Granted, I am not a mechanic at all, I don't work on my saws, or I should say, I wouldn't work on them if they needed any work- my son would. But, I know enough about them to know they run just fine after sitting long spells with mixed gas in them. Once again, I think it is the mix oils' quality that prevents the gumming issue.

I run regular pump gas same as I put in my truck. I don't see the need to blow all that xtra money on fancy gas. Just use quality mix.

Ted

 

[BigMoneyGrip]

When my dad had a store, each shipment of gas was a different color. This was before the ethanol crap that we have now. I know some parts of the country has a different fuel for each season but in MS, I think it's all the same.

I've never seen any evidence that the ethanol fuel "attracts" moisture. I've done many tests of my on and none of them had moisture in them. I used glass fruit jars, one with the top off and the other with a lid and a small vent hole. Each straight gas and mixed gas. The ones with out the lid evaporated first, never showing any signs of containing water. It turned thick like syrup and eventually dried to the crusty scabs that you find in some carbs. The ones with the top and a vent hole, eventually had some to evaporate, but no signs of moisture. This took about 1 1/2 years.

I know that this was not scientific proof, but it was good enough for me.

 

[Snap]

I put Sunoco Race Fuel in all the seasonal and minimally used equipment and bikes.
Some of the mixes have no ethonol and a 2 year or longer shelf life.
It costs quite a bit but with all the carbs that I have to potentially deal with it's worth it to me.

I've also heard from some that aviation gas is good in that respect too.

The Sunoco rep also advised that the higher the octane rating of a gas the less likely it is to gum up, so atleast that is a general start on the problem.

We do not have ethonol free pump gasoline here and closest station is about 5 hours away, so that is not an economical possibility.

 

[Philbert]

Two things:

1) (What Professor Fish said) gasoline today is more complex, and blended for automobile engines, not chainsaws. Some components separate or break down faster than others. Fresh is best.

I am not a chemist, but based on what I have gathered from different sources, I try to buy premium fuel from a station with good turnover traffic; use a good quality, name-brand 2-cycle oil; mix up small amounts of fuel based on my expected, short term needs; date label my fuel mix container and dispose of mixed fuel after 30 days (run through my snow blower in winter or dilute into my car's gas tank otherwise); drain my saws and run them dry if I will not be using them in the next few weeks.

2) Newer carbs are more fussy. That is why Grandpa's old McCulloch will fire up with gas left over from the Carter administration, and a newer Husky or STIHL will balk if the vintage of a current mix is slightly stale. The trade offs on the newer saws are generally positive, but you gotta keep your carbs clean.

JMHO

Philbert

 

[user 64030]

When my dad had a store, each shipment of gas was a different color. This was before the ethanol crap that we have now. I know some parts of the country has a different fuel for each season but in MS, I think it's all the same.

I've never seen any evidence that the ethanol fuel "attracts" moisture. I've done many tests of my on and none of them had moisture in them. I used glass fruit jars, one with the top off and the other with a lid and a small vent hole. Each straight gas and mixed gas. The ones with out the lid evaporated first, never showing any signs of containing water. It turned thick like syrup and eventually dried to the crusty scabs that you find in some carbs. The ones with the top and a vent hole, eventually had some to evaporate, but no signs of moisture. This took about 1 1/2 years.

I know that this was not scientific proof, but it was good enough for me.

I would think that this was too long a time. You could see the results faster by just adding a little water to your E-xx gas, if the water mixes that is the ethanol attracting moisture. IF it separates, it is either ethanol free or already saturated so much it cannot hold any more water. Ethanol will attract moisture, but the levels it get vary greatly, in a container in a shed it would be exposed only to what the humidity in the air is, and this would be minimal. In a gas tank taken from a warm(er) garage to a cold truck bed, or from cool shaded spot out into direct sunlight the temperature change can induce condensation that will be absorbed into an ethanol blended gas.

When you have water in a gas line in an auto what to you add to the tank to a) “dry” the water out and b) help stop freezing? You buy a chemical called gas-dry (used to be on by that name) and it was basically alcohol so the water would mix w/ gas.

I've also heard from some that aviation gas is good in that respect too.

Aviation fuel is required by FAA regs to be ethanol free - WHY? Ethanol will attract enough moisture to allow carb icing at altitudes.... not a real good idea when you can't just pull over and walk.

dw

 

[BigMoneyGrip]

I would think that this was too long a time. You could see the results faster by just adding a little water to your E-xx gas, if the water mixes that is the ethanol attracting moisture. IF it separates, it is either ethanol free or already saturated so much it cannot hold any more water. Ethanol will attract moisture, but the levels it get vary greatly, in a container in a shed it would be exposed only to what the humidity in the air is, and this would be minimal. In a gas tank taken from a warm(er) garage to a cold truck bed, or from cool shaded spot out into direct sunlight the temperature change can induce condensation that will be absorbed into an ethanol blended gas.

When you have water in a gas line in an auto what to you add to the tank to a) “dry” the water out and b) help stop freezing? You buy a chemical called gas-dry (used to be on by that name) and it was basically alcohol so the water would mix w/ gas.




Aviation fuel is required by FAA regs to be ethanol free - WHY? Ethanol will attract enough moisture to allow carb icing at altitudes.... not a real good idea when you can't just pull over and walk.

dw

The whole point of me doing the test was to see if the gas would "draw" the moisture out of the air. It didn't. Pouring water in the gas wouldn't confirm it. I think the problem is all of the other chemicals and additives that are in the gas. Back when we had leaded gas, none of these problems existed. Regular leaded gas is now called race gas. When we are forced to use the E15, the problems will get worse.

 

[Fish]

I never thought it attracted water, just mixed with it. The old time mower carbs had a spring loaded drain button on the bottom of the bowl
to quickly drain the condensed water out, and the glass seperation bowls were to see the water and crap.

 

[user 64030]

Yes, but if in a closed container, under certain situations there will develop condensation on the inside (sweat on a pop bottle). In a gas can this would be absorbed directly if ethanol was in the mix. I doubt there is enough water in most the air (though those in Seattle may differ ) to actually affect teh gas.

dw

 

[stihlrookie]

Ouch

Just back from the station......4.08 per gallon for non-ethanol. Over a dollar more than the 87/89 octane 10% eth. Tacoma took nearly 60 bucks to fill.