Octane question

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Fellas, I appreciate all of the responses and all of the experience.
From all of this I've gained the following:

1) Run at least 89 octane even though the compression in most saws doesn't warrant it.
2) Run E-free (unless you absolutely cant find any, and even then, drain/flush with premix or E-free and run dry before putting in layup).
3) Theres a good mix of beliefs on here about fuels haha.

For my situation, I believe I'll have to run 93 octane, 10% E and then drain/flush with premix, e-free before layup.
I know theres also two trains of thought on storing with fuel/without but I think I'll try the without method.

Again, Sorry for bringing up an old argument, I searched the site for past posts but didnt get info I was looking for.
Has anyone attempted to make a general chainsaw pointers post for all new members? Something that would cover the go to chainsaws and their competition for each task, fuels, tools, storage, etc.?

I'd do it myself but I dont have the experience to back any claims (and dont want to just repeat what I've read/heard).

Probably a pie in the sky idea but just thought I'd ask.

Again, thanks for the responses fellas!
After reading many of the posts here am a little confused about what I would do. Petroleum Gasoline mixed with Alcohol has never caused me any problems in more than twenty years. One time I ordered some OEM hoses which started cracking immediately after installation then ordered non OEM which solved the problem. I make a living at cutting wood. I also have more than fifty years experience. Alcohol needs more volume to produce the same energy so carb adjustments always needs a little richer mixture. Alcohol also burns cooler or at a lower temperature which is more important on hot days. I am very very experienced at higher elevation tuning to get the most out of a saw motor. I always advance timing as the elevation increases. If I bring a saw down to lower elevations and forget to adjust for low altitude a OP can feel the motor vibrate along with sluggish performance. If a OP thinks that a saw is too marginal for tuning they can always retard timing a degree but very unlikely. If a OP needs a little more Octane which is also unlikely even at Sea Level they can add a little premium fuel to their normal premix. Saws in general are lowest of low performers and can run on pretty much any thing except maybe used motor oil. A very big reason suppliers use alcohol in their fuel is to enable low Octane fuel to be used with alcohol which raises overall Octane. Alcohol has about 110 Octane rating. The big if not The BIG concern for most every one is the tune. If you saw does not feel like it is going to run away to the circus then find out why and do not use it all day thinking you check when you get back to your shop. No pull the plug immediately or use a different saw. Thanks
 
After reading many of the posts here am a little confused about what I would do. Petroleum Gasoline mixed with Alcohol has never caused me any problems in more than twenty years. One time I ordered some OEM hoses which started cracking immediately after installation then ordered non OEM which solved the problem. I make a living at cutting wood. I also have more than fifty years experience. Alcohol needs more volume to produce the same energy so carb adjustments always needs a little richer mixture. Alcohol also burns cooler or at a lower temperature which is more important on hot days. I am very very experienced at higher elevation tuning to get the most out of a saw motor. I always advance timing as the elevation increases. If I bring a saw down to lower elevations and forget to adjust for low altitude a OP can feel the motor vibrate along with sluggish performance. If a OP thinks that a saw is too marginal for tuning they can always retard timing a degree but very unlikely. If a OP needs a little more Octane which is also unlikely even at Sea Level they can add a little premium fuel to their normal premix. Saws in general are lowest of low performers and can run on pretty much any thing except maybe used motor oil. A very big reason suppliers use alcohol in their fuel is to enable low Octane fuel to be used with alcohol which raises overall Octane. Alcohol has about 110 Octane rating. The big if not The BIG concern for most every one is the tune. If you saw does not feel like it is going to run away to the circus then find out why and do not use it all day thinking you check when you get back to your shop. No pull the plug immediately or use a different saw. Thanks
Alcohol is more a problem for guys that do not run their saws regularly. However, it does have issues for daily users too. It attracts alot of water, it can cause phase separation, it reacts with some ester based oils to create corrosion.
If I can avoid it I do.
Then other thing about it is something you touched on. It allows refiners to blend garbage streams with it and still hit their octane numbers. This fact alone is way guys have had problems ever sense Alcohol was first blended.
 
Alcohol is more a problem for guys that do not run their saws regularly. However, it does have issues for daily users too. It attracts alot of water, it can cause phase separation, it reacts with some ester based oils to create corrosion.
If I can avoid it I do.
Then other thing about it is something you touched on. It allows refiners to blend garbage streams with it and still hit their octane numbers. This fact alone is way guys have had problems ever sense Alcohol was first blended.
Sure do love it in our race engines! 14 to 1 comp and lots of power. Cost is a little prohibitive but for a few weekends a year it's manageable. It sure raises hell with the joints in my elbows and shoulders (aches for hours) when I get my hands in it for a while though.
 
I've never use Klotz Octane Booster with stabilizer but lot of straight Klotz Octane booster. I ran it in my drag boat, and at the time I ran it in a build Yamaha 400RD. In short it works well in a need for higher octane, it expensive but cheaper than race fuel. High speed detonation has destroyed a lot of motors and I've blow hole between cylinder and hole thru pistons learning this the hard way. Not sure what your need is but really check your tune and spark plug color …error on the rich side just a bit. The convenance booster give is nice but for the most part I mixed fuel to get the octane i needed. I at the time, I ran 110 low lead Aviation fuel with a good premium unleaded fuel. Unleaded fuel octane gets a boost from the lead that still in the 110 low lead fuel. The gain in octane is 3 to 5 points. the low amount of lead added into unleaded fuel …the octane boost is quick, it a nonlinear curve. In the day leaded fuel was 3 grams/gallon, and the fuel is saturated…additional lead over 3 grams would have no effect on octane. Pull the lead out of fuel it drops in octane 8 points, so it doesn’t take much lead to gain octane. I was running 12.5:1 in my boat...with close chamber heads 1860 cmf induction on a 1968 L88 427 built into a 440-bracket motor. 132mph hydro and I was blowing some fuel thru that motor… 20 gallon in 10 passes (basically 2.5 miles to 20 gallon of fuel)! I’m not sure what the compression ratio was on the RD, I was running a Dayton head on that bike, it was setup as a 3-wheeler sand Hill climber drags trike. Pulling 3rd gear hole shots with 12 paddle haulers for the hook-up. I loved the Klotz products. Sorry if I’m off topic… I’m suggesting always run fresh fuel is always a good rule. Ethanol free fuel properly stabilized is good for 2 years but it loses octane. E10 or E20 fuel is only good for few months at best in my opinion.
 
I've never use Klotz Octane Booster with stabilizer but lot of straight Klotz Octane booster. I ran it in my drag boat, and at the time I ran it in a build Yamaha 400RD. In short it works well in a need for higher octane, it expensive but cheaper than race fuel. High speed detonation has destroyed a lot of motors and I've blow hole between cylinder and hole thru pistons learning this the hard way. Not sure what your need is but really check your tune and spark plug color …error on the rich side just a bit. The convenance booster give is nice but for the most part I mixed fuel to get the octane i needed. I at the time, I ran 110 low lead Aviation fuel with a good premium unleaded fuel. Unleaded fuel octane gets a boost from the lead that still in the 110 low lead fuel. The gain in octane is 3 to 5 points. the low amount of lead added into unleaded fuel …the octane boost is quick, it a nonlinear curve. In the day leaded fuel was 3 grams/gallon, and the fuel is saturated…additional lead over 3 grams would have no effect on octane. Pull the lead out of fuel it drops in octane 8 points, so it doesn’t take much lead to gain octane. I was running 12.5:1 in my boat...with close chamber heads 1860 cmf induction on a 1968 L88 427 built into a 440-bracket motor. 132mph hydro and I was blowing some fuel thru that motor… 20 gallon in 10 passes (basically 2.5 miles to 20 gallon of fuel)! I’m not sure what the compression ratio was on the RD, I was running a Dayton head on that bike, it was setup as a 3-wheeler sand Hill climber drags trike. Pulling 3rd gear hole shots with 12 paddle haulers for the hook-up. I loved the Klotz products. Sorry if I’m off topic… I’m suggesting always run fresh fuel is always a good rule. Ethanol free fuel properly stabilized is good for 2 years but it loses octane. E10 or E20 fuel is only good for few months at best in my opinion.
 
First of all I don't know didly about 104+, never used it. Secondly, dieseling is a tune up problem not a combustion/compression problem. I've been a mechanic and race engine builder my whole life and I can fix any dieseling vehicle with a screwdriver! Too rich of a mixture in the idle circuit will cause dieseling on a hot engine or one with high compression. While 104+ has seemed to solve your problem, a screwdriver is a much more cost effective choice.
Well... ummmm NO! Dieseling is caused by carbon deposits in the combustion chamber that are hot enough to ignite fuel. Dieseling, as you noted, can be solved with a "turn of the screwdriver".. That's true, if you look at it that you've made the idle mixture too lean to run without a proper spark from a plug.
70s' cars used what was called an "anti diesel solenoid" which basically was a base against which the idle screw rested. It was electrically operated. When the ignition was turned off, the anti diesel solenoid made the throttle plate completely close. Hence the engine couldn't diesel, as there wasn't any fuel to do so with.
Leaning out any fuel source may well stop dieseling, but the root cause of dieseling in a carbureted engine is carbon deposits that are hot enough to ignite incoming fuel mixtures, and a throttle plate and mixture setting that continues to supply a combustible mixture to the combustion chamber.. Compression has nothing to do with it.
 
Well... ummmm NO! Dieseling is caused by carbon deposits in the combustion chamber that are hot enough to ignite fuel. Dieseling, as you noted, can be solved with a "turn of the screwdriver".. That's true, if you look at it that you've made the idle mixture too lean to run without a proper spark from a plug.
70s' cars used what was called an "anti diesel solenoid" which basically was a base against which the idle screw rested. It was electrically operated. When the ignition was turned off, the anti diesel solenoid made the throttle plate completely close. Hence the engine couldn't diesel, as there wasn't any fuel to do so with.
Leaning out any fuel source may well stop dieseling, but the root cause of dieseling in a carbureted engine is carbon deposits that are hot enough to ignite incoming fuel mixtures, and a throttle plate and mixture setting that continues to supply a combustible mixture to the combustion chamber.. Compression has nothing to do with it.
Most commonly it's the sparkplug that's the ignition source.
 
I've never use Klotz Octane Booster with stabilizer but lot of straight Klotz Octane booster. I ran it in my drag boat, and at the time I ran it in a build Yamaha 400RD. In short it works well in a need for higher octane, it expensive but cheaper than race fuel. High speed detonation has destroyed a lot of motors and I've blow hole between cylinder and hole thru pistons learning this the hard way. Not sure what your need is but really check your tune and spark plug color …error on the rich side just a bit. The convenance booster give is nice but for the most part I mixed fuel to get the octane i needed. I at the time, I ran 110 low lead Aviation fuel with a good premium unleaded fuel. Unleaded fuel octane gets a boost from the lead that still in the 110 low lead fuel. The gain in octane is 3 to 5 points. the low amount of lead added into unleaded fuel …the octane boost is quick, it a nonlinear curve. In the day leaded fuel was 3 grams/gallon, and the fuel is saturated…additional lead over 3 grams would have no effect on octane. Pull the lead out of fuel it drops in octane 8 points, so it doesn’t take much lead to gain octane. I was running 12.5:1 in my boat...with close chamber heads 1860 cmf induction on a 1968 L88 427 built into a 440-bracket motor. 132mph hydro and I was blowing some fuel thru that motor… 20 gallon in 10 passes (basically 2.5 miles to 20 gallon of fuel)! I’m not sure what the compression ratio was on the RD, I was running a Dayton head on that bike, it was setup as a 3-wheeler sand Hill climber drags trike. Pulling 3rd gear hole shots with 12 paddle haulers for the hook-up. I loved the Klotz products. Sorry if I’m off topic… I’m suggesting always run fresh fuel is always a good rule. Ethanol free fuel properly stabilized is good for 2 years but it loses octane. E10 or E20 fuel is only good for few months at best in my opinion.
100LL avgas is rated any the lean/rich scale that's aviation specific although it roughly corresponds with 100 octane R+M/2 that's used to rate pump fuel. One problem with blending premium with race gas or av gas is its not a mathematical scale that determines your end octane rating. In most cases this doesn't matter, but in some applications it does. If your motor requires it run straight race gas. It's a fools errand to guess with an expensive race motor.
Octane boosters like Klotz raise your octane less then 1 number. Unless the treat rates get ridiculous, which introduces all sorts of problems. Most boosters use aromatics like toluene and some use MMT. MMT has a ceiling where by its ineffective and it produces lots of rusty color deposits which can cause pre ignition. The aromatic based boosters cause throttle response issues and are very hard on rubber and plastic, plus they are nasty to inhale, which is why they were phased out from use in pump gas.
 
Most commonly it's the sparkplug that's the ignition source.
If that's where the carbon deposits are located.. then absolutely.. Decades ago, when I was a much younger man, getting an engine " de-coked" ( de carbonized) was a regular maintenance thing. Literally, putting a hose down the intake of a running engine was a method of removing carbon deposits from an engine. The detonation of the steam i the combustion chamber shook the carbon loose.
Now, we use Seafoam :).. It doesn't detonate the carbon off from the combustion chamber, it dissolves it.
Even with today's gas formulas .. we're still burning a carbon based fuel.
 
If that's where the carbon deposits are located.. then absolutely.. Decades ago, when I was a much younger man, getting an engine " de-coked" ( de carbonized) was a regular maintenance thing. Literally, putting a hose down the intake of a running engine was a method of removing carbon deposits from an engine. The detonation of the steam i the combustion chamber shook the carbon loose.
Now, we use Seafoam :).. It doesn't detonate the carbon off from the combustion chamber, it dissolves it.
Even with today's gas formulas .. we're still burning a carbon based fuel.
Typically the ground strap of the plug begins to glow before carbon and if you think about how it's positioned this makes sense. Not that carbon can not glow as well, especially on the exhaust valve or valves.
As for sea foam. As far as I am concerned it's pure snake oil. I've ran it through two cycles and then inspected after with a bore scope and it didn't do a thing except full the mufflernwith partially burnt and unburnt sea foam.
 
I love a good gas or oil thread lol.
Quick question, has anyone ever had a chainsaw detonate/spark rattle on 87 octane?
I havent seen/heard it happen yet. They're so small and rev so high it's hard to make them detonate. Motor's that detonate useally do it at low rpm with high load, chainsaws dont run at low rpm under load.
My buddies cut a lot of firewood with regular gas and husky oil mixed 32-1 without issue.
I run supreme because that's what I have for the bikes and atv, they dont like regular, they rattle on it. I fill one big jug then pour a gallon into a marked jug for the saws, mixing one gallon at a time.
 
I love a good gas or oil thread lol.
Quick question, has anyone ever had a chainsaw detonate/spark rattle on 87 octane?
I havent seen/heard it happen yet. They're so small and rev so high it's hard to make them detonate. Motor's that detonate useally do it at low rpm with high load, chainsaws dont run at low rpm under load.
My buddies cut a lot of firewood with regular gas and husky oil mixed 32-1 without issue.
I run supreme because that's what I have for the bikes and atv, they dont like regular, they rattle on it. I fill one big jug then pour a gallon into a marked jug for the saws, mixing one gallon at a time.
I've not had it happen to me or anyone I know, but I've seen pics of pistons out of saws that are obviously detonating.
Stale fuel and a lean tune will do it.
 
I doubt you’re running 128:1, so your math is probably off a bit. 1 gallon of oil makes the same number of gallons of mix as your ratio.

50:1 = 50 gallons to 1 gallon
32:1 = 32 gallons to 1 gallon
Perhaps I wasn't clear...

The Klotz Octane Booster ("KOB") is not an oil. KOB will increase the octane rating of gasoline. One (1) ounce of KOB per gallon of gasoline raises the octane rating by two (2) numbers. This is a mix ratio of 128:1. If the pump gas starts with an octane rating is 87, then one (1) ounce of KOB per gallon would raise the gasoline octane rating to 89. In my area, I can readily find ethanol-free gasoline with an octane rating of 88. I like to run 90+ octane in my 2-stroke engines, so I use the KOB to reach the 90 octane rating. I then add the appropriate amount of 2-stroke oil (Klotz R-50). My preference is to run a mix somewhere between 40:1 and 50:1...usually a bit closer to the 40:1 level.

JQ
 
The Echo manual says to use at least 89 octane gas, with a maximum of 10% ethanol.
I only have 87 octane e-free fuel around here (I'm not going to pay $11.25/gallon for 110 octane e-free fuel thats sold near me).

Should I just use 93 octane @ 10% ethanol and call it a day?
Or will adding something like (Lucas Oil octane booster) to my 87 octane, e-free fuel serve me better?

I already plan on draining the fuel tank and running dry for storing my Echo CS-620p any length greater than 3 days.
I know the optimal solution would be to just use 89+ octane, e-free but I just cant find any within 45 mins+ drive.


Thanks for your time fellas!
The books says 89.

What's the problem?
 

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