I think when this question comes up, people are wondering if the higher octane will help as far as longevity. At least that's what I used to wonder. I knew my mower was running fine already.
What Gas Octane Rating For Mower ?
- Thread starter ChrisD46
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Originally Posted by gman2304
^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
I wonder why that is..? I have an Echo string trimmer and a Hitachi (Tanaka engine) leaf blower and both require 89 per the manual.
^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
I wonder why that is..? I have an Echo string trimmer and a Hitachi (Tanaka engine) leaf blower and both require 89 per the manual.
Originally Posted by 92saturnsl2
Originally Posted by gman2304
^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
I wonder why that is..? I have an Echo string trimmer and a Hitachi (Tanaka engine) leaf blower and both require 89 per the manual.
89 minimum per echo.
https://www.echo-usa.com/Warranty/Learn-About-Ethanol
Originally Posted by gman2304
^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
I wonder why that is..? I have an Echo string trimmer and a Hitachi (Tanaka engine) leaf blower and both require 89 per the manual.
89 minimum per echo.
https://www.echo-usa.com/Warranty/Learn-About-Ethanol
*Thanks , my Quick Trip sells non - ethanol in 87 octane .
Originally Posted by wag123
Small air cooled lawn mower engines have such a low compression ratio that they will run good on 81 octane gas, if you could buy it.
87 octane gas will work fine. Higher octane than this would be a waste of money, but E0 would be preferable to E10 if it is readily available in your area..
Originally Posted by wag123
Small air cooled lawn mower engines have such a low compression ratio that they will run good on 81 octane gas, if you could buy it.
87 octane gas will work fine. Higher octane than this would be a waste of money, but E0 would be preferable to E10 if it is readily available in your area..
*No 91 non - ethanol where I live (unless you buy the boutique 91 octane expensive , small cans from Home Depot or Lowes) .
Originally Posted by MRtv
All of my lawn tools recommend using zero ethanol fuel. That is for my 4 cycle and 2 cycle tools. One of the tools came recommended to use 91 octane. So all of them get 91 non-ethanol fuel. That includes my Honda mower. Have not had any problems doing that for quite a few years now. Just costs a bit more for the summer stock of fuel but it isn't really that big a deal. Maybe a dollar more of cost going into the 5 gal. gas can.
Originally Posted by MRtv
All of my lawn tools recommend using zero ethanol fuel. That is for my 4 cycle and 2 cycle tools. One of the tools came recommended to use 91 octane. So all of them get 91 non-ethanol fuel. That includes my Honda mower. Have not had any problems doing that for quite a few years now. Just costs a bit more for the summer stock of fuel but it isn't really that big a deal. Maybe a dollar more of cost going into the 5 gal. gas can.
Originally Posted by Superflan
Does a thing such as an Ethanol remover treatment really exists?
No it does not. The only way an additive like that could remove the ethanol is to precipitate it out and for a bunch of reasons there's no way that's happening.
If he means he's removing it with water (which seems like a popular idea here on Bitog) then it also removes some of the additives put into the gasoline. No one ever seems to talk about that.
Does a thing such as an Ethanol remover treatment really exists?
No it does not. The only way an additive like that could remove the ethanol is to precipitate it out and for a bunch of reasons there's no way that's happening.
If he means he's removing it with water (which seems like a popular idea here on Bitog) then it also removes some of the additives put into the gasoline. No one ever seems to talk about that.
I run regular e-10 I'm my equipment during the summer. It's used every week, so no issues. The last fuel purchase of the season is non ethanol, and it gets treated with stabil and tcw-3 at 640:1.
I also keep 15 gallons of non ethanol generator fuel thats treated. I relpace/rotate that after 6 months.
I also keep 15 gallons of non ethanol generator fuel thats treated. I relpace/rotate that after 6 months.
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If it's gasoline, put it in and mow.
Originally Posted by gman2304
Originally Posted by 92saturnsl2
All my 2-cycle equipment recommends 89 octane for some reason. Therefore I just fill my jugs up with 89 so I'm not having to use separate gas for different equipment.
^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
The Echo 89 octane recommendation is a throwback to a previous era.
The reason that Echo recommended 89 octane in the first place is because of the additional detergents that 89 octane had compared to what cheap 87 octane once had (most 87 octane fuels contained little or NO detergents back in the day, some still don't). The engine does not need the higher octane for resistance to detonation, the compression ratio is too low to require it, Echo just wanted you to use gas that had some added detergent to reduce carbon deposits. Carbon deposits can cause pre-ignition which is FAR more harmful. Modern Top Tier 87 octane gas has an adequate amount of detergent, basically rendering the 89 octane recommendation obsolete (unless you want to use gas that is not Top Tier).
This information came directly from the colorful German gentleman (I forget his name) who was Echo's chief 2-cycle engine design engineer and director of service training during the late 1980's through the early 2000's. His service training classes were legendary.
Originally Posted by 92saturnsl2
All my 2-cycle equipment recommends 89 octane for some reason. Therefore I just fill my jugs up with 89 so I'm not having to use separate gas for different equipment.
^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
The Echo 89 octane recommendation is a throwback to a previous era.
The reason that Echo recommended 89 octane in the first place is because of the additional detergents that 89 octane had compared to what cheap 87 octane once had (most 87 octane fuels contained little or NO detergents back in the day, some still don't). The engine does not need the higher octane for resistance to detonation, the compression ratio is too low to require it, Echo just wanted you to use gas that had some added detergent to reduce carbon deposits. Carbon deposits can cause pre-ignition which is FAR more harmful. Modern Top Tier 87 octane gas has an adequate amount of detergent, basically rendering the 89 octane recommendation obsolete (unless you want to use gas that is not Top Tier).
This information came directly from the colorful German gentleman (I forget his name) who was Echo's chief 2-cycle engine design engineer and director of service training during the late 1980's through the early 2000's. His service training classes were legendary.
When you mix oil with gasoline you lower the octane. Quite a bit the 32 to one, like I run in most stuff.
so they start with higher octane.
I was having problem with Chonda, turned out it was a blocked jet. I was running it on starting fluid, and every spray it knocked severely. My other engines will not. So I assume the Chonda has higher compression.
Regardless, 91 no alcohol no lead is all I can get.
Rod
so they start with higher octane.
I was having problem with Chonda, turned out it was a blocked jet. I was running it on starting fluid, and every spray it knocked severely. My other engines will not. So I assume the Chonda has higher compression.
Regardless, 91 no alcohol no lead is all I can get.
Rod
This.
Here in Manitoba, Canada we have pretty much three gasoline options:
87 octane with 10% ethanol
89 octane with 5% ethanol
91 octane with 0% ethanol
In every small engine I own, I run the 91 octane option. Not because my small engines require anything high octane, but because I dislike ethanol. Small engines tend to sit more than they run (especially here due to the long cold winters) and I don't want my fuel to absorb moisture. Some guys with carbureted two-cycle snowmobiles still insist on running ethanol fuels, and this often results in a burn down.
In my daily drivers, I just use the cheaper 87 octane.
87 octane with 10% ethanol
89 octane with 5% ethanol
91 octane with 0% ethanol
In every small engine I own, I run the 91 octane option. Not because my small engines require anything high octane, but because I dislike ethanol. Small engines tend to sit more than they run (especially here due to the long cold winters) and I don't want my fuel to absorb moisture. Some guys with carbureted two-cycle snowmobiles still insist on running ethanol fuels, and this often results in a burn down.
In my daily drivers, I just use the cheaper 87 octane.
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Originally Posted by Malo83
Whenever i fill up my truck with 89 i'll fill up my gas can for the mower. runs the same, maybe a little more cleaner in the gas.
Funny you said that. When I go the gas station with a jerry can to buy ethanol free fuel for my OPE, I always put about five or ten bucks in my vehicle first to clear the gas stations's line. My theory is the last guy probably bought E10 for his car, and the line is still full of E10 when I go to fill my jerry can. If i am only buying a gallon or two for the jerry can, a good percentage of my fill could be E10 if I don't clear the line by putting some fuel in my car first.
Super anal, I know. But I'd rather not chance it not knowing how much E10 remains in the pump before I start.
Whenever i fill up my truck with 89 i'll fill up my gas can for the mower. runs the same, maybe a little more cleaner in the gas.
Funny you said that. When I go the gas station with a jerry can to buy ethanol free fuel for my OPE, I always put about five or ten bucks in my vehicle first to clear the gas stations's line. My theory is the last guy probably bought E10 for his car, and the line is still full of E10 when I go to fill my jerry can. If i am only buying a gallon or two for the jerry can, a good percentage of my fill could be E10 if I don't clear the line by putting some fuel in my car first.
Super anal, I know. But I'd rather not chance it not knowing how much E10 remains in the pump before I start.
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Originally Posted by wag123
The Echo 89 octane recommendation is a throwback to a previous era.
The reason that Echo recommended 89 octane in the first place is because of the additional detergents that 89 octane had compared to what cheap 87 octane once had (most 87 octane fuels contained little or NO detergents back in the day, some still don't). The engine does not need the higher octane for resistance to detonation, the compression ratio is too low to require it, Echo just wanted you to use gas that had some added detergent to reduce carbon deposits. Carbon deposits can cause pre-ignition which is FAR more harmful. Modern Top Tier 87 octane gas has an adequate amount of detergent, basically rendering the 89 octane recommendation obsolete (unless you want to use gas that is not Top Tier).
This information came directly from the colorful German gentleman (I forget his name) who was Echo's chief 2-cycle engine design engineer and director of service training during the late 1980's through the early 2000's. His service training classes were legendary.
It's hard to believe the tiny bit of gasoline additives is a big issue when 2 stroke gas has a bunch of oil and associated additives in it.
The Echo 89 octane recommendation is a throwback to a previous era.
The reason that Echo recommended 89 octane in the first place is because of the additional detergents that 89 octane had compared to what cheap 87 octane once had (most 87 octane fuels contained little or NO detergents back in the day, some still don't). The engine does not need the higher octane for resistance to detonation, the compression ratio is too low to require it, Echo just wanted you to use gas that had some added detergent to reduce carbon deposits. Carbon deposits can cause pre-ignition which is FAR more harmful. Modern Top Tier 87 octane gas has an adequate amount of detergent, basically rendering the 89 octane recommendation obsolete (unless you want to use gas that is not Top Tier).
This information came directly from the colorful German gentleman (I forget his name) who was Echo's chief 2-cycle engine design engineer and director of service training during the late 1980's through the early 2000's. His service training classes were legendary.
It's hard to believe the tiny bit of gasoline additives is a big issue when 2 stroke gas has a bunch of oil and associated additives in it.
Brossoit?
Originally Posted by propuckstopper
When I go the gas station with a jerry can to buy ethanol free fuel for my OPE, I always put about five or ten bucks in my vehicle first to clear the gas stations's line. My theory is the last guy probably bought E10 for his car, and the line is still full of E10 when I go to fill my jerry can. If i am only buying a gallon or two for the jerry can, a good percentage of my fill could be E10 if I don't clear the line by putting some fuel in my car first.
This has been discussed many times over the years.
The residual fuel is typically about .2 -.3 gallon.
When I go the gas station with a jerry can to buy ethanol free fuel for my OPE, I always put about five or ten bucks in my vehicle first to clear the gas stations's line. My theory is the last guy probably bought E10 for his car, and the line is still full of E10 when I go to fill my jerry can. If i am only buying a gallon or two for the jerry can, a good percentage of my fill could be E10 if I don't clear the line by putting some fuel in my car first.
This has been discussed many times over the years.
The residual fuel is typically about .2 -.3 gallon.
