Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Happy holidays every one! ... bought the toro 1028 OXE back in October, right after the very first early snow storm. Was not able to try it in snow... I added the startron stabilizer And filled up the tank with 93 octane. I tested the new baby, showed off without spinning augers... But now it's a long time unused. My question is: is it okay for the fuel to sit in the carb for such a long time? Thanks!

JoelKlein wrote:
No.

carlb wrote:

According to you. High octane will make the engine worse. Why? And how? Pls explain. Thanks

My local dealer said to run 87 octane and I'd be fine as long as I run some stabilizer which has to do more with the ethanol and water in the gas than the octane. So far everything works just fine.

borat wrote:

In my shop it would be safe to say that at least 50% of all "No Starts" that come into the shop every year are from STALE FUEL... Thats why u should 100% run stabilizer in your fuel.... and at the cost of stabilizer $1.50 / 10L of gas, makes for pretty cheap insurance...

As far as "Getting BAD Gas" lve been in business for Ten years this year and service approx 300 machines every year and i RARELY come across "BAD GAS" maybe twice in my Ten years have i even seen it...so its extremely unlikely u will get bad gas... what is more likely is stale fuel...

For example before i started using stabilizer about 6 years ago i would tune up customers snowblowers in the spring or even mid to late october and they wouldn't start them till the first snow in january and i would get a call saying it wont start...so i'd drive out to there place to find out that the fuel has gone stale.. drian the old fuel out put new in and it starts right up...so after about 15 calls in one season i started using stabilizer and lve never had a problem since.

l use 87 octane fuel,  l have tried 94 octane but didn't see any benifit from using the higher octane, so why pay 94 when 87 does the same job without any drawbacks..

Well, I own probably 40 pieces of equipment from OPE, to outboard motors, to ATVs, to snowmobiles, to motorcycles, to cars and trucks.  Never an issue with stale fuel. 

However, I do proper maintenance and drain fuel from equipment that will be stored for long durations.  Nonetheless, I still keep fuel in plastic five gallon containers at my camp for six to eight months and it works just as fine as fresh fuel.  So, the stories about fuel going bad in one month sound a bit contrary to my experience. 

I would wager that the stale fuel your customers experience is much more than 30 days old and likely much older.   I would also wager that it was kept in a fuel tank that was left less than 1/4 full.  Under those conditions, it has room to evaporate and deteriorate.  If their tanks were kept either right empty or completely full before storage, and they ran their carbs dry, they probably would not have had a problem.

And I stopped using stabilizers ten or fifteen years ago.  Haven't regretted it yet.

And for all the 40 engines you use regular 87 octane?

For example just last week i had a 2008 ariens come in NO START the lady says she started it a couple of months ago to move it in the garage... went to start last week and it wont start.. this is a tecumseh 6hp ohv...anyways all i did was drian the old fuel out and put new in and it started first pull.. and this could of been pervented if she used stabilizer..of course she had no idea what stabilizer even is.. and thats a good example of a snowblower that started only a couple months of ago.. of course lm not saying that will happen to every snowblower but is it worth the risk for a couple of dollaurs for stabilizer??

And for the customer sake its just makes things easier then they dont half to remember "should i leave fuel in it" "half or full" "how long is fuel good for" all these questions are gone if they just use stabilizer, then they have no worries at least in regards to storage and fuel..

most new briggs mowers are coming with stabilizer (replacable cartiridge) built in the fuel caps...because they've had so many problems with stale fuel causing no starts... it just makes sense.. thats my opinion.

JoelKlein wrote:

 

The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.

The compression ratio of your engine determines the octane rating of the gas you must use. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.

In a low compression engine(8:1), it is sufficient to burn low (87) octane fuel because the heat of compression is not high enough to ignite it spontaneously. However, as compression is raised, higher octane ratings are necessary to prevent this auto-ignition. Since higher octane gasoline burns at about the same temperature as low octane, it generates the same amount of power. The reason a high compression, high octane engine develops more power is because the higher compression raises the BMEP--Base Mean Effective Pressure: More pressure = more horsepower. Timing is usually advanced a bit also for a better power curve and the engines are usually adjusted to injest more air/fuel mixture. They also usually produce this power at a higher RPM than a low compression engine. THUS: There is NO advantage to using high octane fuel in an engine that requires low octane, and at best, it is a waste of money. Indeed, some high octane fuels can contain compounds that could be harmful to low compression engines.

However, using low octane rated fuel in a high compression engine is harmful. Because the gasoline auto-ignites at a different point than the sparkplug and usually earlier, there are two flame fronts burning. When the flame fronts collide, excess temperature and pressure are generated. We may hear it as a knocking noise also known as "detonation." This melts the aluminum of the piston while at the same time hammering it. Total destruction is the result.

Conclusion: Use fuel with the octane rating recommended by the manufacturer.

Lean running conditions are a separate scenario not related to octane rating. Lean fuel mixtures also auto-ignite more easily and burn hotter than proper mixtures of gasoline and air regardless of octane rating. The result, however is the same: Total destruction of the piston.

Okay, I fully understand why we cant use 87 octane in a high performance engine without damaging it. . But you still didn't explain why we can't use 93 octane In a low Compression engine! You wrote that it may Contain some elements, what are those elemants? To worst it can happen is $$$$ in trash! But damage???? Or make it perform worse?!

Simple 93 octane burns hotter, in a car this isn't much of an issue but in a small engine it could be. Also elevation affects engines and you need less octane or something bad happens.

The safest thing you can do is run the right gas. In my Toro 1028 I run 87 octane from the local station. This works. If you already have 93 octane I guess run it until it you run out then

buy 87 octane. Save your money. I can't imagine it doing any damage in the short term.