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dennis thompson
01-04-2018, 5:40 AM
My snow blower was very difficult to start so I brought it to a small engine repair shop. The carburetor that came with the unit (a Toro) was plastic:eek:! I've seen a lot of carburetors in my life but never a plastic one, until now. Anyway he replaced the carburetor with a metal one ,spark plug and gas filter, and warned me several times about bad gas and the need to keep it for only 2-3 months, even when using Sta bil.

What do you do with your gas ( I have to mix it with oil) after it gets old?
Thanks

Mike Cutler
01-04-2018, 6:07 AM
Plastic carbs' he body at least, are very common now. You can rebuild one, or clean it, once or twice, and then that's it. He was right to replace it with an all metal one.

All of my small engines use 91-93 octane with SeaFoam added as a stabilizer and a varnish inhibitor. When I'm done the engines are run until the crab is run dry and the tanks are emptied with a manual pump I have.
All of my cars use the same octane of gas, so any gas I have that's getting old, 2-3 months seems a little quick to me though, goes into one of the cars or the garden tractor. The tractor sees year round duty.
I don't need to mix a lot of gas with oil normally., at least not for the bigger machines. My chainsaw, weed whacker and leaf blower, need oil, but they're easy to empty and run dry. I've kept gas mixed with oil and SeaFoam in a container through the winter and it seems fine come spring when I need it again. Been doing it this way for years. The carb on the leaf blower and weed whacker are plastic. The chainsaw is metal.
I like the SeaFoam product better than regular Stabil. It seems to be working for me. I needed to use my generator this past October and it hadn't been started in over 8 years. It started up just fine.

Steve Eure
01-04-2018, 6:41 AM
I have been running 87 octane in my 2-cycle engines since forever. I had always run them dry or emptied the tanks after each use because of the ethanol issue in the gas. Every year I have had to take them to a small engine repair shop for the same reason. The plastic fuel lines in the tanks would become brittle and break and have to be replaced. I was told by all the mechanics that the manufacturers recommended not to use ethanol fuel and keep the tank at least 1/4 full at all times even during storage so that the gaskets and o-rings would stay lubricated. They said use a non-ethanol fuel mixed with the right ratio of oil and add a stabilizer.

Perry Hilbert Jr
01-04-2018, 7:34 AM
I burn 10 to 15 gals of gas in my tractor every month. Left over gas is just mixed slowly with the tractor gas and used up in the tractor. Maybe a half gallon of old stuff to a tank of new. As for the two cycle, we never mix up more than a gallon at a time and we have weed eaters, chain saws, pole saws, etc. A gallon gets used fairly quickly during most of the year. The pole saw is used the least and the tank is dumped out after every use. I recently found out about a nearby gas station that sells real gas without added ethanol for off road use. Had the kid pick up 5 gallons for me. Like a buck a gallon higher than the contaminated gas sold everywhere.

George Bokros
01-04-2018, 7:41 AM
I started buying gas without ethanol for my small equipment. The ethanol absorbs moisture just like the winter fuel treatment to prevent fuel line freeze up. The ethanol is hard on the small engine carburetors.

You can find locations nationwide that have ethanol free fuel here pure-gas.org

roger wiegand
01-04-2018, 9:14 AM
Following the recommendation of my equipment supplier, I use "premium" gas in my various tools, no stabilizer. On those tools that allow it I shut of the supply and run them dry at the end of the season. What's in the tank just sits over the winter or summer and has never presented any sort of problem. The 5 gal can gets used until it's empty, over the winter that can be 5-8 months. Some tools have gone decades with this practice and continue to work just fine. I suspect there's a lot more folklore about "bad gas" than actual problems.

Grant Wilkinson
01-04-2018, 9:16 AM
To address the OP's question, I just dump the remaining oil/gas mix into one of the cars. I don't use a lot of 2-stroke mix so I'm usually talking about a couple of quarts max left at the end of the season. Adding to over 25 gallons in the car doesn't make any difference to how the car runs at all. Now, these are older cars without 17 computers monitoring everything from gas caps to tire pressure.

michael langman
01-04-2018, 9:34 AM
I just bought a new metal carburetor for my 10hp simplicity snow thrower that is 24 years old, for 15.00 . Amazing. I also bought the rebuild kit for the original carburetor if the cheap new one doesn't last. But it probably will.
I use stabil in regular 87 octane gas. When I add it to my equipment I add an ounce of marvel mystery oil to keep the internal parts oiled and varnish free, and an ounce of seafoam to keep the pistons cleaner.

Stan Calow
01-04-2018, 10:21 AM
I dump gas leftover from lawn mowing into the truck at end of season. Same with gas for snowthrower. My QuikTrip and several other places sell ethanol-free gas which is all I will use for power equipment.

John C Cox
01-04-2018, 10:29 AM
Plastic carbs have been around since the 1980's... My 1989 Evinrude outboard has a plastic carb that's now pushing almost 30 years old.... They are pretty good these days. The problem isn't because of plastic - it's because of the gas drying out and gumming up everything.

The problem they did have for a while was tightening the bolts too tight and cracking.... But it seems like their designs are better now and have more or less sorted that out.

On the plus side - they don't rust or corrode like steel and aluminum units do... Pop open a 20 year old Plastic carb and it's shiny as new inside...

But when a carb costs $15 or $20 to replace - it's not even worth rebuilding it.... For $20 - I would just replace the carb with a new one at the beginning of the season....

Jim Koepke
01-04-2018, 11:27 AM
My weed eater would gum up over the winter. The service department at the local dealer told me it needs to be run about once a month to keep the fuel from gumming up the works. Stihl markets a fuel for two stroke engines that is supposed to be stable for a couple of years. It isn't cheap.

Some very old gas has worked fine in many instances in my experience. Maybe in the past gasoline wasn't stable. My 5 gallon container was filled a couple of years ago and still works fine in my chain saw and weed eater.

jtk

George Bokros
01-04-2018, 11:37 AM
[QUOTE=Jim Koepke;2761850 Stihl markets a fuel for two stroke engines that is supposed to be stable for a couple of years. It isn't cheap.[/QUOTE]

This is correct but they also recommend using 91 octane gas without ethanol. That is why I use only 91 octane ethanol free fuel in all my small engines now. See my post above for a link to find ethanol free fuel in your area.

I also run all my equipment to empty for over winter and I also run my rototiller to empty after use in the spring since is sets until fall.

You can also use Seafoam in your gas for small engines just make sure you mix it according to the directions on the Seafoam can. I have used it an my mower and rototiller have never run better.

John C Cox
01-04-2018, 12:29 PM
The 91 octane gas is due to the high performance nature of Stihl engines.... Stihl engines put out a LOT of power for their size - even compared to a Poulan, Weed Eater, or McCullough home owner type engine. And they need good gas because of that.

Evinrude factory recommendation for my 1960 9.5hp 2 stroke recommends at least 40 octane.... Even the 89 15hp which puts out nearly 20hp recommends at least 60 octane... And they don't seem to run any better with 93 than whatever comes out of the "standard" pump.... The factory recommends no ethanol on the old ones - but that is because of the shellac coated cork carb float and shellac sealer used on gaskets. Ethanol can eat the shellac off and the cork float becomes soaked and won't float and the shellac sealed gaskets leak.. The "new" engines (aka built since the 1980's) use plastic floats and and modern gasket material. They don't seem to have problems with this.....

My lawn mowers all recommend standard unleaded.... Those engines aren't designed to make use of anything better.. These cheap 4 stroke utility engines have low compression (around 7.5:1) and a TON of compression release built into the camshaft.. It's telling that the go-cart racing guys can pretty easily get 20 hp out of a 6.5hp rated horizontal shaft 4 stroke pressure washer/lawn mower engine.... But they also have problems because while they can make the power - the engines aren't designed to handle the power - and they split the block in half, snap connecting rods, crack pistons, and flatten camshaft lobes... You won't find that problem on a Stihl...

Mac McQuinn
01-04-2018, 12:36 PM
I prefer StarTron as a fuel stabilizer although since getting a local supply of REC90 Fuel, I'm using that with good success. My equipment runs better on a daily basis and I was pleased to disassemble a fuel petcock on my motorcycle and find no residue recently.
Mac

Bruce Wrenn
01-04-2018, 9:33 PM
Ever look up the MSDS for Seafoam? Alcohol, naptha and light oil, most likely diesel fuel.

Andrew Gibson
01-05-2018, 9:54 AM
If you can get it, run ethanol free gas. I am lucky and have a station around the corner that sells the corn free stuff. I run it in all my lawn equipment and in my carburetor pickup truck. the carb on the truck is a Holley street demon with a phenolic fuel bowl, basically a revision of the old thermoquad carbs Chrysler made in the 70s. The plastic bowl is supposed to lower fuel temps by up to 20*, I have been running the carb for two years now and very much like it.

Mike Cutler
01-05-2018, 10:06 AM
Ever look up the MSDS for Seafoam? Alcohol, naptha and light oil, most likely diesel fuel.

That's pretty interesting. Looks like I could blend my own. I might experiment a bit this spring.
I wonder if Kerosene would be a better choice than diesel?

Grant Wilkinson
01-05-2018, 11:30 AM
On the subject of running things dry before putting them away for the season, you may want to be sure to drain the carb float bowl. I can run my snowblower and my outboard "dry", but there is still gas in the float bowl - not much, but enough to varnish up the innards. The manuals for both my snowblower and my outboard advise to drain the float bowls for just that reason.

Bob Leistner
01-06-2018, 10:02 AM
Actually, plastic carbs have been around since the 60's. Anyone ever hear of a Carter Thermoquad? They weren't exactly great carbs and the plastic bodies were notorious for warping,but it would insulate the fuel and keep it cooler.

Art Mann
01-06-2018, 12:03 PM
I find the idea that small engine manufacturers can't design engines that work with 10% alcohol after all these years to be absolutely ridiculous.

Bob Leistner
01-06-2018, 6:06 PM
It is not that they can't.It requires the use of more expensive materials. Since there is no benefit to the use of alcohol in gas it would just be more money wasted. Please don't bother with the theories, I'm very well versed in the stories and am not going to discuss it further.

Dave Lehnert
01-06-2018, 6:18 PM
My snow blower was very difficult to start so I brought it to a small engine repair shop. The carburetor that came with the unit (a Toro) was plastic:eek:! I've seen a lot of carburetors in my life but never a plastic one, until now. Anyway he replaced the carburetor with a metal one ,spark plug and gas filter, and warned me several times about bad gas and the need to keep it for only 2-3 months, even when using Sta bil.

What do you do with your gas ( I have to mix it with oil) after it gets old?
Thanks



Plastic Carb, I rebuilt an older push mower engine and it had a plastic gear inside.

John Lanciani
01-06-2018, 8:06 PM
It is not that they can't.It requires the use of more expensive materials. Since there is no benefit to the use of alcohol in gas it would just be more money wasted. Please don't bother with the theories, I'm very well versed in the stories and am not going to discuss it further.

Why would it be money wasted? There are lots of folks like myself that can’t reasonably (cost and or effort) get ethanol free gas. The waste of money comes from repairing and replacing parts and equipment or buying high priced canned fuels because the manufacturers are too cheap to fix the issue.

Ronald Blue
01-06-2018, 9:10 PM
I always find the whole ethanol thing laughable at best. Issues from ethanol are rare and usually more likely related to lack of care in general. I consider us to be experts on it here where I am. We have been using it since about 1980 and it would be tough to find a station not selling it here. (Illinois/Iowa/Missouri) area. I haven't had an engine issue with a vehicle or small engine that I could blame on the ethanol in years. In the early days there were some issues because the ethanol blend cut crud loose in the fuel system and lead to problems with plugged filters and orfices. Just as the unleaded fuel created some issues in older engines. I also haven't bothered to "winterize" my mowers, string trimmers, and other small engines ever. My Dixie Chopper I sold last summer was 17 years old. Never did I ever do anything special with the fuel system on it. Can gas go bad? Definitely! It reeks when it does. As for what to do with the old gas the suggestions of using it in the vehicles is excellent.

Art Mann
01-06-2018, 10:12 PM
It is not that they can't.It requires the use of more expensive materials. Since there is no benefit to the use of alcohol in gas it would just be more money wasted. Please don't bother with the theories, I'm very well versed in the stories and am not going to discuss it further.
There was a time when just about all small engines were affected by alcohol. The worst for me was a Tecumseh engine. Today, I have smalll engines made by Kohler, Briggs and Stratton, Honda, Echo, and Harbor freight. They have all been working fine on standard pump gas for several years. I did nothing more than a dose of Stabil in the last tank full at the end of the season and an occasional dose of Seafoam. This is not a theory. Why don't I have any problems? Am I really that lucky? I think modern design is the most likely explanation. There is an obvious benefit to manufacturers to design in compensation for alcohol. Consumers are more satisfied with their products.

As stupid as it is, gas diluted with alcohol is here to stay, even though it has no environmental benefits and does not reduce cost or increase supply of domestic fuels. Manufacturers realized that a long ago and took action. There are many reasons why small engines don't run well. Bad gas is just one of them.

Jim Koepke
01-09-2018, 3:39 PM
Why would it be money wasted? There are lots of folks like myself that canít reasonably (cost and or effort) get ethanol free gas. The waste of money comes from repairing and replacing parts and equipment or buying high priced canned fuels because the manufacturers are too cheap to fix the issue.

Who do you think makes money when an engine owner has to buy replacement parts?

Who makes money selling the high priced canned fuels with the manufacturer's name on the label?

Spending a few dollars more to make a better product often loses customers in the store due to the higher price. Too many people judge a product on price as opposed to quality.

jtk

John Lanciani
01-10-2018, 4:06 AM
Who do you think makes money when an engine owner has to buy replacement parts?

Who makes money selling the high priced canned fuels with the manufacturer's name on the label?

Spending a few dollars more to make a better product often loses customers in the store due to the higher price. Too many people judge a product on price as opposed to quality.

jtk

I agre completely Jim. Bob seemed to be implying that there was no value to anybody for the mfrs to fix the problem from their end.My feeling is that they have every incentive not to fix it. Mfrs and repair shops just blame the fuel, never acknowledging that they could mitigate the problem with just a few small changes. Ethanol is not going away any time soon; the auto companies have accepted this fact, why wonít the small engine manufacturers.

Ole Anderson
01-10-2018, 9:24 AM
Coast Guard regulations require special fuel hose since ethanol spiked gas came out, so there is some affect on rubber as well. That being said, up until this year I have never had a problem using 87 octane E10 gas in any of my two stroke engines. Two Stihl saws a Stihl trimmer and a Stihl blower and a Toro snowblower. This year I did replace the carb on my oldest 018 saw, who knows what the problem was. But now that my local Kroger gas station sells "recreational" 90 octane ethanol-free fuel, my next 2 gallon can will be filled with that as it is only about a buck a gallon more than regular. I do run them dry at the end of the season. Frustrating they can't or won't design the fuel systems to accommodate at least E10.

Myk Rian
01-10-2018, 3:35 PM
Left over gas is just mixed slowly with the tractor gas and used up in the tractor.
^^^^This^^^^

Larry Edgerton
01-15-2018, 6:50 AM
I started buying gas without ethanol for my small equipment. The ethanol absorbs moisture just like the winter fuel treatment to prevent fuel line freeze up. The ethanol is hard on the small engine carburetors.

You can find locations nationwide that have ethanol free fuel here pure-gas.org (http://pure-gas.org)

Bingo! Have not had to touch my fuel systems since I started doing this.