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km101
04-16-2017, 11:57 AM
Bought a small lightweight chainsaw for tree trimming and small chores around the house. This saw says a fuel mix of 1:40 with synthetic oil and 89 octane gas. All my other 2cycle equipment use a 1:32 fuel mix and regular gas.

My question is this; if I run 1:32 in the new saw will the extra oil foul the plug or gum something up? What about the high octane fuel? I really don't want to have two separate mixes to keep track of. If it doesn't matter, I'll just run it like the others. But if it does, then it may be more trouble than it's worth.

What say ye? I know there are those out there with LOTS of experience with saws.
Thanks!

Goatwhiskers
04-16-2017, 12:09 PM
In my experience a little extra oil doesn't hurt a thing. Been doing it for years on the advice of my chainsaw distributor. Just makes a bit more smoke. GW

Josh Smith
04-16-2017, 12:12 PM
Should be fine. I used to run richer than that in an outboard.

It's an anti-pollution measure is all.

Oil will kill catalytic converters where those are a concern.

Regards,

Josh

Iowa Fox
04-16-2017, 12:40 PM
My son in law gave me a Mcculloch that one of his co workers was throwing away. It was a classic example of ethanol fuel, rotted lines crumbling primer bulb and plugged carb. For less than 10 bucks of parts including a carb kit she was ready. The fuel cap said 1-40 but all I had was 1-32 for my other stuff. Well that saw will not even start on 1-32. The local farm store has little bottles of 1-40 sythetic oil for 1 gallon of gas. I mixed up a gallon and I'll be darned if that saw doesn't start first pull every time. Usually when I tried a heavier mix I just got a little extra smoke and more power but not this time with this saw.

I'd say give the 1-32 a try and if it doesn't work well just turn the saw upside down and give the 1-40 a try. Kind of a pain in the butt keeping the different mixes. Just try to avoid ethanol at all cost if you can where you live, its the kiss of death in small engines.

crowbuster
04-16-2017, 07:35 PM
I run 40:1 in everything with the highest octane I can get. 93 I think. 100s of hrs on saws no problems.

jonp
04-16-2017, 07:40 PM
One of my saws takes 1:25. Run it at what they say and don't worry about it.

David2011
04-16-2017, 08:12 PM
There was recently a similar discussion on RCGroups.com regarding the amount of oil in larger gasoline model airplane engines. I have several gasoline engines from 1.4 to 2.4 cu. in. (26-40 cc) Some experiments that were done scientifically (actual measurements taken) showed that a little more power was gained at 32:1 over the lower oil concentrations. Speculation was that the extra oil helped the ring seal better and it did not lead to fouling the spark plug. The overwhelming oil of choice for use in RC airplanes was Red Line Racing Oil. I had been using Husqvarna 2 cycle oil which produces thick black (think tar-like) exhaust residue. I purchased some Red Line but have not tried it yet. Flyers that have used it say the residue is negligible. It's transparent red and looks very clean. I found it at a motorcycle shop where they told me most of their sales of that oil were to RC flyers.

David

Petrol & Powder
04-16-2017, 08:55 PM
I can't imagine that the octane rating would matter on a 2 stoke chainsaw engine. So for the 87 vs 89 octane question, I would buy the 87 and carry on. However, if it is at all possible to purchase non-ethanol fuel in your area, I would highly recommend non-ethanol fuel in ALL of your small engine applications. That alone will save you a lot of headaches. Octane is simply a rating of how much heat & pressure a fuel can tolerate. There's no additional power to be had by using higher octane fuel UNLESS you have the corresponding compression ratio to utilize that higher octane fuel.

As for the 32:1 vs 40:1 mix - If it will run on the 32:1, go for it. The only downside is a bit more smoke. Small, two-stroke engines like the ones found in chainsaws, trimmers, leaf blowers, etc. are basically disposable. That's not to say they will wear out quickly; they will not. With maintenance they can give decades of service. However, when they do finally wear out they are generally not worth repairing. By the time you wear out a chainsaw engine the rest of the saw is about done. I'm not sure if there would be a significant difference in life expectancy of chainsaw engine rated for 40:1 that was run on a richer oil mix of 32:1. In any event, at the end of its life I wouldn't spend $250 to repair a $350 saw that was 15 years old.

If the richest fuel/oil mix for your small two-strokes is 32:1 and all of your equipment will actually run on 32:1 - use that mix as your lowest common denominator mix for all of your two-stroke engines. The benefit is simplified fuel storage, one fuel/oil mix for everything. The only downside is a little more smoke.

Skunk1
04-16-2017, 09:00 PM
More oil does not hurt anything. Just don't burn ethanol in it. May be good for cars that drive everyday but not for small engines. My brother in law and I both run stihl's. He contact the company about this question as small engines have changed over the years. They informed him that more will not hurt, less will.

Moleman-
04-16-2017, 09:27 PM
Brother in law (a DR) has a few Husqvarna pro grade chainsaws that are supposed to run 50:1 or perhaps it's 60:1. He somehow got the saw hot enough to melt the piston 8-9 years ago. Brought it to me saying it just stopped running and wouldn't start and the local Husqvarna dealer said the like new saw wasn't worth fixing. Had no compression but would run a short time with a little 90wt oil in the cylinder. Took it apart and found the melted piston had trapped the rings, thus the no compression. They sell new piston/cylinder kits for them so I put one in and the saw was back in business. Asked what ratio he was running and suggested he back down to 32:1 or 40:1 and only keep one mix of gas instead of one for each two cycle mixture he had. Haven't had to replace a piston since.

Plate plinker
04-16-2017, 09:46 PM
We use this now and our tools run like a raped ape.
http://trufuel50.com/product-info/


https://hw.menardc.com/main/items/media/ARNOL006/ProductMedium/6525638_ip_d.jpg (https://hw.menardc.com/main/items/media/ARNOL006/ProductLarge/6525638_ip_d.jpg)

runfiverun
04-16-2017, 10:02 PM
I'd have no problem running a little more oil.
but I'd run the extra octane.
I run the ethanol free premium in all of my small engines, especially anything that might have some fuel left in it for a year or so.
I run it in the boat, 4 wheelers, the lawn mowers, [and the Mustang] they sit in storage over the winter and only gets started occasionally.
it adds up to maybe 35 gallons in all the little engines, in a years time.

cheap insurance to cough up the extra $17.50 a year.

sawinredneck
04-16-2017, 11:43 PM
We use this now and our tools run like a raped ape.
http://trufuel50.com/product-info/


https://hw.menardc.com/main/items/media/ARNOL006/ProductMedium/6525638_ip_d.jpg (https://hw.menardc.com/main/items/media/ARNOL006/ProductLarge/6525638_ip_d.jpg)



This stuff is a great start! In this day and age, with quality 2stroke oils, there is no need to run anything at 32:1 or higher. The older oils weren't that great, thus the higher mix ratio. No, it won't hurt anything, other than a shorter spark plug life, to run richer.
Also the octane rating matters a lot, the better the fuel, the longer before it settles into water! The non-ethanol is without a doubt the best for OPE engines because it doesn't seperate as bad. Keep in mind most ethanol fuels are rated for two or less months of storage now, they separate and collect water after that.
I use the Royal Purple two stroke oil, they say you can run the synthetic at 100:1 but I'm anal about my two stroke equipment. I run it at 50:1 with the best grade (least amount of alcohol content) I can get my hands on.
I have a Shindiwa M231 powerhead I bought around 2004, I've never had to clean the carb and each spring it starts within five pulls, with the gas in the tank from last fall.
Quality of gas and oil mix really does matter.

54bore
04-16-2017, 11:53 PM
I have worked in the woods all of my life as a logger/timber faller, I run a stihl 660 and use stihl HP Ultra 2 cycle oil 50:1 ratio, my saw runs 6 hrs a day. I have zero issues with fouled plugs etc.

jim147
04-17-2017, 12:14 AM
While the can gas mix is pricey if you are going to use it only here and there it is worth it.

I put sta-bil and a lead substitute in every five gallon jug I get. Mowers chainsaws and weed eaters start right up after sitting all winter. If I have a rare problem, a little moonshine and sea foam added to the fuel takes care of it.

dragon813gt
04-17-2017, 12:20 AM
We use this now and our tools run like a raped ape.
http://trufuel50.com/product-info/


https://hw.menardc.com/main/items/media/ARNOL006/ProductMedium/6525638_ip_d.jpg (https://hw.menardc.com/main/items/media/ARNOL006/ProductLarge/6525638_ip_d.jpg)



This is great if you don't have ethanol free fuel available in your area. But it's quite expensive at $20+ a gallon. I will stick w/ ethanol free for slightly over $3 a gallon plus the oil. If you use very little the premix cost doesn't mater. But burn up even a few gallons a year and it adds up quick.

jonp
04-17-2017, 04:22 AM
I use Lucas Ethanol Additive. It's supposed to kill the bad effects of the ethanol although I can't say I've ever seen the bad ethanol fuel do anything to my stuff. I also add a little Marvel to all oil. I don't know if it does any good but I do it anyways. If your going to let the fuel sit any length of time use StaBil.

Lloyd Smale
04-17-2017, 05:32 AM
yup higher octane isn't the answer for 2 strokes unless they had the compression bumped up and NEED it. It makes them harder to start and ALOT of the premium fuel today gets it higher octane rating from adding alcohol and alcohol isn't what you want in a two stroke motor. Octane is a burn retardant. It makes fuel burn cooler. It use is in high compression motors that tend to have spark detonation. Run it in a motor that isn't designed to use it and you will actually loose power.
I can't imagine that the octane rating would matter on a 2 stoke chainsaw engine. So for the 87 vs 89 octane question, I would buy the 87 and carry on. However, if it is at all possible to purchase non-ethanol fuel in your area, I would highly recommend non-ethanol fuel in ALL of your small engine applications. That alone will save you a lot of headaches. Octane is simply a rating of how much heat & pressure a fuel can tolerate. There's no additional power to be had by using higher octane fuel UNLESS you have the corresponding compression ratio to utilize that higher octane fuel.

As for the 32:1 vs 40:1 mix - If it will run on the 32:1, go for it. The only downside is a bit more smoke. Small, two-stroke engines like the ones found in chainsaws, trimmers, leaf blowers, etc. are basically disposable. That's not to say they will wear out quickly; they will not. With maintenance they can give decades of service. However, when they do finally wear out they are generally not worth repairing. By the time you wear out a chainsaw engine the rest of the saw is about done. I'm not sure if there would be a significant difference in life expectancy of chainsaw engine rated for 40:1 that was run on a richer oil mix of 32:1. In any event, at the end of its life I wouldn't spend $250 to repair a $350 saw that was 15 years old.

If the richest fuel/oil mix for your small two-strokes is 32:1 and all of your equipment will actually run on 32:1 - use that mix as your lowest common denominator mix for all of your two-stroke engines. The benefit is simplified fuel storage, one fuel/oil mix for everything. The only downside is a little more smoke.

Plate plinker
04-17-2017, 05:35 AM
Yep a bit spendy but still worth the money. You can get it in gallons now but unsure if there is a price break. Seems that loggers and others that would run for hours a day could benefit from it if it was available in drums.

JimB..
04-17-2017, 05:43 AM
Yep a bit spendy but still worth the money. You can get it in gallons now but unsure if there is a price break. Seems that loggers and others that would run for hours a day could benefit from it if it was available in drums.

I bought a case on sale, really just like the cans so now I refill them with non-ethanol gas with stabil added. I only use maybe 5gal a year.

cptjack
04-17-2017, 06:42 AM
at 8.00 a qt ,I use high test only gas around here that has no ethanol

rototerrier
04-17-2017, 07:32 AM
1) More oil than is necessary simply blows out the pipe and/or fouls the plug
2) A higher oil ratio = a lower fuel ratio = running leaner.

Most small engines now come preset and expect the fuel/oil ratio to match those preset settings. If you deviate from the recommendations by adding more oil, then you will be running the engine leaner based on its preset tune. If you add less oil, then you will be running richer. It's not an issue if you can tune the engine. But if you plan on just running it as you received it and not turning it, then it's probably best to stick with the recommended mixture since that's what it's most likely setup for.

I always run Ethanol free fuel mixed with RedLine 2T at 40:1 from my chainsaws and blowers to my $500 heavily modified RC helicopter and plane Engines. But I also tune my engines so they all run perfectly on it.

Personally, I've never seen a situation that called for more than a 40:1 ratio.

Many many years ago, before I got into high dollar RC engines, I ran everything at 50:1 and even used Amsoil 100:1 at, you guessed it, 100:1. No issues, ever.

Per the engine modifier's request and instruction, I switched to using 40:1 RedLine and just made that change across the board. Figured what was good for my $500+ engines was more than good enough for my cheap weed wacker, blower, and chain saw engines.

DerekP Houston
04-17-2017, 08:19 AM
We use this now and our tools run like a raped ape.
http://trufuel50.com/product-info/


https://hw.menardc.com/main/items/media/ARNOL006/ProductMedium/6525638_ip_d.jpg (https://hw.menardc.com/main/items/media/ARNOL006/ProductLarge/6525638_ip_d.jpg)




Yeah, i use so little fuel for my weedeater and leafblower i switched to Trufuel as well. no more clogged lines or ethanol issues, just one pull and they fire right up. Ridiculously over priced for what it is though.

44man
04-17-2017, 08:31 AM
I had nothing but troubles with oil, carbon and plugged exhaust. I used Stihl synthetic at 50 to 1 along with all other brands. Oil would drip from mufflers all over the garage floor. I was always fixing.
I found Opti II and all problems went away. It comes in a little pack for a gallon of gas. 50 to 1.
Every octane gas here has alcohol in it. Have to go to a Liberty station to get rid of it, place is too far and it is expensive.
Sea Foam seems to take care of it.

rond
04-17-2017, 08:56 AM
I run premium in all my air cooled engines, as per the owners manual.

dragon813gt
04-17-2017, 11:20 AM
If you can't buy ethanol free gas you can make it from ethanol laden gas. All you do is add water, agitate and let it settle out. The water picks up the ethanol and then you drain it out. You wan to use distilled water but this process works. I did it before a station locally started selling ethanol free gas.

funnyjim014
04-17-2017, 12:22 PM
I run eth free 91 with the factory oil that you dump into 1gal of fuel. My farm boss can tell the difference with the eth free fuel

sac
04-17-2017, 01:00 PM
Like Rototerrier said you will have to tune for the new mix, I tune my saws every time I use them depending on the day.

prestonj12
04-17-2017, 04:31 PM
If I'm not using a lot I buy the ethanol free premix at Lowes. The stuff they sell by the quart for around $6. That stuff has no additives, detergents etc. 92 octane. I run a tank of this stuff about every third tank. It's sorta like a tuneup in a can. All my 2 cycle toys get this treatment. Keeps em from carb rebuilds so far.


Sent from my iPhone using Tapatalk

David2011
04-17-2017, 05:25 PM
I can't imagine that the octane rating would matter on a 2 stoke chainsaw engine. So for the 87 vs 89 octane question, I would buy the 87 and carry on. However, if it is at all possible to purchase non-ethanol fuel in your area, I would highly recommend non-ethanol fuel in ALL of your small engine applications.

You are correct. Octane really doesn't matter in unmodified small engines. The cylinder volume is just too small for octane to be an issue. If you don't mind paying the price and they'll sell it to you, get some 100 Low Lead gasoline at a general aviation airport. Don't get excited about 100 Octane; that's just a re-ignition retardant and it won't burn an engine up. If you burn enough, the lead will build up on the spark plug. Aviation gasoline is much cleaner than automotive pump gas and has no alcohol added. It will not gum or varnish up in storage. I'm changing to 100LL for my bigger radio controlled airplanes because it doesn't gum and varnish if I don't get to fly for a while. Even if you don't want to pay for av gas all season, at least run it as the last tank or two before the storage season and the carb won't be sticky or varnished up next time you need the tool.

too many things
04-17-2017, 06:42 PM
check at your sunoco station many Carey the al free called rec gas

snowwolfe
04-17-2017, 08:42 PM
I been using 50 to 1 for decades on all my 2 strokes and never had any failures.

dkf
04-18-2017, 12:41 AM
I usually use Amsoil Sabre 100:1 oil in aircooled (weedeaters, chainsaws, etc) at around 60:1 with 87 octane pure gas. My watercooled two stroke outboards get Amsoil Sabre outboard for the premix ones at 70:1 and Amsoil HP Injecter in the oil injected ones again with 87 octane pure gas. You can run richer, it burns very clean. If you don't have the higher compression that requires higher octane fuel then it does nothing to help. All my 2 stroke outboards don't even have a 7:1 compression ratio, higher octane is a waste for them.

In the R/C gas boat world on 30cc and smaller engines (some making well over 6hp) they run coleman fuel with 8-10oz of oil per gallon.


If you can't buy ethanol free gas you can make it from ethanol laden gas. All you do is add water, agitate and let it settle out. The water picks up the ethanol and then you drain it out. You wan to use distilled water but this process works. I did it before a station locally started selling ethanol free gas.

If you do that you have to start with higher octane fuel. (like 93) When you pull the ethanol out of the fuel the octane will drop.

dragon813gt
04-18-2017, 08:01 AM
I'm aware. I wasn't going to write out all the details when they're readily available online. I was simply pointing out another option.

HangFireW8
04-18-2017, 11:14 AM
The oil ratio depends primarily on the quality of oil used, and after that the tuning of the engine. 87 is usually fine unless you have a compression engine mod. Keep in mind more oil brings down the octane, less oil retains octane.

-HF

Rick459
04-18-2017, 02:06 PM
the little bottles of 2 stroke oil are approx. 2.6 oz. mix 1 bottle to every gallon of gas used. you will be fine.

Sent from my SAMSUNG-SM-N920A using Tapatalk

texasnative46
04-18-2017, 02:52 PM
To All,

I just wish that I could FIND some alcohol-free gas nearby. = I've found none nearer to me than 2 hours round-trip away by car.
(As I have about a dozen pre-1965 Johnnyrude OB motors, I need a lot of it, too.)

yours, tex

km101
04-18-2017, 05:14 PM
Thanks for all the info. I have learned A LOT about small engines and fuel.
Like texasnative46 I wish I could find non-ethanol fuel or some place that would sell me Ava-gas. I can't find a source here north of the DFW metromess. But I have learned enough here to solve my problem!

THANKS to all of you!

dragon813gt
04-18-2017, 05:39 PM
Lone Star Mobil in Allen, TX is the closest one I could find north of Dallas. But it's not exactly close by.

Petrol & Powder
04-18-2017, 07:07 PM
2 stoke engines typically don't have an oil sump or pressurized lubrication system. The only lubricant available in the crankcase is the oil/gas mixture. That oil/gas mixture has a lot of demand placed on it; it must lubricate the big end of the connecting rod, the wrist pin, the rings, the piston skirt and the two outer crankshaft bearings. The good news is because it's constantly being replenished; that gas/oil mix only has to work for a brief period of time. More oil improves the lubrication but it comes at the cost of less efficient combustion and less power. Like most things in life - it's a compromise.
If the bearings can stand a thinner oil mix then there's an advantage to running more gas and less oil. It comes down to what the engine can tolerate. A little more oil doesn't hurt much but it comes at the cost of smoke, plugs that foul easier and slightly reduced power.

As for alcohol and gasoline - The ethanol causes more problems in small engines than it's worth. It also causes huge problems with storage of fuel. Fuel stabilizer certainly helps but pure gas is even better.

Octane rating: this is probably one of the biggest scams around and it's easy to sell because people want to believe it's true.
High compression engines need high octane gas to run without detonation [knocking or pinging]. Increasing the compression ratio (to a point) is one of the ways to increase power but high compression requires high octane fuel to take advantage of that higher compression ratio.
Using high octane fuel in an engine that doesn't need it to operate; DOES NOT PRODUCE ADDITIONAL POWER. Putting high octane fuel in a low compression engine doesn't magically make it run better, stronger or more efficiently. In fact, it may even be less efficient.
When people buy high octane fuel and tell themselves that they are getting: more power, better gas mileage or some other perceived benefit - they are just engaging in a self fulfilling prophecy. They want to believe they are getting better performance so they do believe they are getting better performance. The fuel companies are happy to sell you more expensive gasoline and they are not going to educate you.
Now, there are some high compression engines that have the ability to produce maximum power on high octane fuel and compensate for lower octane fuel when necessary. Those engines have knock sensors and computer controlled ignition and fuel systems that reduce power output when they are fed lower octane fuel. However, a low compression engine that runs fine with 87 octane fuel will not magically produce more power if you supply it with 93 octane fuel.

km101
04-18-2017, 08:13 PM
Ethanol free gas is not available within 50+ miles of where I live, because of the Clean Air Act, so that's out. Home Depot has Tru-fuel for $9.55/qt+ Tax and that's out too! Guess I will mix to manufacturers recommendation an just keep 'em seperate. Or I could continue to use my bigger saw and give this one to someone I don't like. :)

km101
04-18-2017, 08:16 PM
Lone Star Mobil in Allen, TX is the closest one I could find north of Dallas. But it's not exactly close by.

Thank you sir! Just noticed your post. I will try to give them a call.

dragon813gt
04-18-2017, 08:18 PM
Puregas.org or get the app.

dkf
04-19-2017, 01:18 AM
Ethanol free gas is not available within 50+ miles of where I live, because of the Clean Air Act, so that's out. Home Depot has Tru-fuel for $9.55/qt+ Tax and that's out too! Guess I will mix to manufacturers recommendation an just keep 'em seperate. Or I could continue to use my bigger saw and give this one to someone I don't like. :)

VP is also making several premixed small engine fuels. My local farm/hardware store has been carrying it, they also carry the Stihl canned premix fuel.

https://vpracingfuels.com/small-engine-fuels/#sef

Lloyd Smale
04-19-2017, 06:35 AM
yup octane is a burn retardant. It slows and cools the burning of your fuel. Using it in a motor that doesn't have enough compression to warrant it makes your motor run worse. Snowmobiles are a good example. THey have to start when its real cold out. Take a stock snowmobile and run premium fuel in it and I can about guarantee you that it will be harder to start and foul plugs faster. Petrol and powder is absolutely right. Add octane to a motor that doesn't have enough compression to need it and you are NOT going to gain power. In fact you will make your fuel harder to ignite and burn cooler. Add to that they fact that a lot of pump fuel today uses alcohol to get its higher octane rating and you compound the problem in a 2 stroke.
2 stoke engines typically don't have an oil sump or pressurized lubrication system. The only lubricant available in the crankcase is the oil/gas mixture. That oil/gas mixture has a lot of demand placed on it; it must lubricate the big end of the connecting rod, the wrist pin, the rings, the piston skirt and the two outer crankshaft bearings. The good news is because it's constantly being replenished; that gas/oil mix only has to work for a brief period of time. More oil improves the lubrication but it comes at the cost of less efficient combustion and less power. Like most things in life - it's a compromise.
If the bearings can stand a thinner oil mix then there's an advantage to running more gas and less oil. It comes down to what the engine can tolerate. A little more oil doesn't hurt much but it comes at the cost of smoke, plugs that foul easier and slightly reduced power.

As for alcohol and gasoline - The ethanol causes more problems in small engines than it's worth. It also causes huge problems with storage of fuel. Fuel stabilizer certainly helps but pure gas is even better.

Octane rating: this is probably one of the biggest scams around and it's easy to sell because people want to believe it's true.
High compression engines need high octane gas to run without detonation [knocking or pinging]. Increasing the compression ratio (to a point) is one of the ways to increase power but high compression requires high octane fuel to take advantage of that higher compression ratio.
Using high octane fuel in an engine that doesn't need it to operate; DOES NOT PRODUCE ADDITIONAL POWER. Putting high octane fuel in a low compression engine doesn't magically make it run better, stronger or more efficiently. In fact, it may even be less efficient.
When people buy high octane fuel and tell themselves that they are getting: more power, better gas mileage or some other perceived benefit - they are just engaging in a self fulfilling prophecy. They want to believe they are getting better performance so they do believe they are getting better performance. The fuel companies are happy to sell you more expensive gasoline and they are not going to educate you.
Now, there are some high compression engines that have the ability to produce maximum power on high octane fuel and compensate for lower octane fuel when necessary. Those engines have knock sensors and computer controlled ignition and fuel systems that reduce power output when they are fed lower octane fuel. However, a low compression engine that runs fine with 87 octane fuel will not magically produce more power if you supply it with 93 octane fuel.

44man
04-19-2017, 08:41 AM
yup octane is a burn retardant. It slows and cools the burning of your fuel. Using it in a motor that doesn't have enough compression to warrant it makes your motor run worse. Snowmobiles are a good example. THey have to start when its real cold out. Take a stock snowmobile and run premium fuel in it and I can about guarantee you that it will be harder to start and foul plugs faster. Petrol and powder is absolutely right. Add octane to a motor that doesn't have enough compression to need it and you are NOT going to gain power. In fact you will make your fuel harder to ignite and burn cooler. Add to that they fact that a lot of pump fuel today uses alcohol to get its higher octane rating and you compound the problem in a 2 stroke.
This is true from both of you, it is just a waste of money unless you run a Ferrari. Almost every vehicle says 87 octane. Too much is not good at all.
The crazy woman down the road had a Subaru, the old one with the flat VW engine and some mechanic told her to use high test so that is all she bought and had nothing but trouble. Now she has a tiny SUV and I bet she still feeds it the most expensive gas.
All small engines use 87. Either way alcohol is just no good, decreases gas mileage too, eats some rubber hoses, collects moisture and on and on.
They came out with E85 or whatever, almost all alcohol and car makers void the warranty if you use it.
My biggest gripe is having to pay road tax when I buy gas for small engines and lawn mowers.
Long ago Amoco sold good gas, so pure we used it in lanterns, almost white gas. No lead.
I bought some gas up town one time, Sonoco (spelling) and could watch the fuel gauge drop. I put BP in and am getting 18.5 MPG with a big 4 Runner 8 cyl. Constant 4 wheel. It reads out on the dash. I turn the air on and still get 18.3 MPG. That is on side roads too. 87 octane.
One thing to watch is the battery, mine was bad and I took it over from Carol when we bought her a newer one, she never got better then 16 MPG. Alternator was working overtime. Changing the battery made the mileage jump.
My friend has a little car that shuts the alternator off when the battery is full, stores power in a big capacitor for when needed. It sips gas.
Too much oil is no good in two strokes if it has bearings. If an engine has bushings you better use what the instructions say, if 25 to 1 never put 50 to 1. The engine will seize. The cheap chain saw made in Canada had steel against steel. Not even a bushing. Pullun or how you spell it.
I have a Husky backpack blower and I could not start it when using Stihl synthetic at 50 to 1. No compression. Rings were carboned in so tight they broke when I could not move them. I had to buy a new piston and rings. Soaking did not help, they were locked.
Oil is important, even brand.

dragon813gt
04-19-2017, 09:57 AM
VP is also making several premixed small engine fuels. My local farm/hardware store has been carrying it, they also carry the Stihl canned premix fuel.

https://vpracingfuels.com/small-engine-fuels/#sef

NAPA carries VP fuels. At least all the ones around here do. Which means if yours doesn't they can get it. They have the small engine cans right at the front door when you walk in, can't miss it. It's not cheap but you can at least buy it five gallons at a time.

Rick Hodges
04-19-2017, 10:02 AM
My Stihl owners manual for my weed wacker specifies 50:1 and 91 octane fuel. They warn against ethanol, but do state that it can run on 87 octane but to be careful as it will run hotter with the regular fuel.

I have a place near me that sells 91 octane ethanol free at the pump for $3.649/gallon at the pump. I use that and mix 50:1 for all my two stroke needs. This after having to have the fuel system rebuilt in my Husqvarna chainsaw due to the lines and plastic getting brittle from the ethanol. I don't use that much two stroke fuel and it makes good sense to me to pay a little more for decent gas.

JonB_in_Glencoe
04-19-2017, 11:03 AM
I had nothing but troubles with oil, carbon and plugged exhaust. I used Stihl synthetic at 50 to 1 along with all other brands. Oil would drip from mufflers all over the garage floor. I was always fixing.
I found Opti II and all problems went away. It comes in a little pack for a gallon of gas. 50 to 1.
Every octane gas here has alcohol in it. Have to go to a Liberty station to get rid of it, place is too far and it is expensive.
Sea Foam seems to take care of it.
about 10 to 15 (maybe 20?) years ago, I was doing some backyard/redneck wrenching on lawn equipment as a part time business...mostly due to Minnesota's switch to ethanol. There were lots of giveaways, that just needed carb work.

BUT also, I was given (for free), the nicest gas powered Stihl hedge trimmer, it ran but was problematic...the only issue was oil/carbon filled screen in muffler (spark arrester?).
The person said they only used Stihl Oil, I suspect he was among the crowd that thinks 50:1 is good and 40:1 is better. I use Stihl chain saws and I quit using Stihl oil about 10 years ago, when I stumbled onto a large box of 2.6 oz bottles John Deere synth 2 cycle oil (maybe a hundred bottles?), it is red like Amsoil...I mix it 50:1 with non-oxy gas, but if I get a little sluggishness and smoky exhaust I add a little Gas, to lean it a bit. I still have a few of those left, when I run out, I'll probably start using Amsoil.

I am also a big fan of Seafoam, I always give a small engine a dose of Seafoam to the gas (or gas/oil mix) after a storage period...to clean out any varnish that may have 'set' during a season of sitting around.

km101
04-19-2017, 02:32 PM
Called VP Racing Fuels at corporate in San Antonio. They said that all Walmart stores carry their premix in 40:1. It's in a white can and just says "SEF", but if you look on the back it has the VP logo and info. Still spendy at $6.40-ish a quart, but I won't use too much in my weed trimmer.

Also supposed to be available at AutoZone and Napa. If it's not on the shelf, they can order it from their warehouse for you. And you can order 1 gal., 5 gal., and 55 gal containers on-line but be prepared for the price!

just FYI

historicfirearms
04-19-2017, 09:25 PM
You guys in texas should look at your local airport and ask for 100LL, prounounced as "hundred low lead". If they ask tell them its for your ultra lite. It will cost around $5 a gallon. Its great fuel that takes years to degrade. I put it in all my engines that sit for extended time, but dont use it in anything with a catalytic converter. The lead will plug cats up.

44man
04-20-2017, 09:22 AM
Lead was an anti knock additive but the greeny wienies said it was poison and it is true. Then alcy came in to reduce pollution but reduced mileage so more gas is used along with more smog. Then the catalytic to heat more and change exhaust. The thing burns fuel that the engine should use. It all adds to cost.
Engines are made better so it helps, Oils are better too. Long ago as a mechanic, 50,000 was good but now 300,000 is broken in. Air filters and oil filters are better.
Much was learned from racing engines but the use of nitro methane for power makes them rebuild an engine after the race.
This is interesting.
Nitromethane exhaustExhaust gas (https://en.wikipedia.org/wiki/Exhaust_gas) from an internal combustion engine whose fuel includes nitromethane will contain nitric acid (https://en.wikipedia.org/wiki/Nitric_acid) vapour, which is corrosive, and when inhaled causes a muscular reaction making it impossible to breathe. People exposed to it should wear a gas mask (https://en.wikipedia.org/wiki/Gas_mask).[15] (https://en.wikipedia.org/wiki/Nitromethane#cite_note-15) The condensed nitric acid-based residue left over in a glow-fueled model engine after a model-flight session can also corrode their internal components, usually mandating use of a combination of kerosene (https://en.wikipedia.org/wiki/Kerosene) to neutralize the residual nitric acid, and an "after-run oil" (often the lower-viscosity "air tool oil" variety of a popular preservative oil (https://en.wikipedia.org/wiki/Marvel_Mystery_Oil)) for lubrication to safeguard against such damage, when such an engine is placed into storage.

HangFireW8
04-21-2017, 12:14 AM
Octane is not a "burn retardant". It is two things. An 8 Carbon atom molecule, and a burn speed rating based on that molecule.

-HF

texasnative46
04-21-2017, 12:39 PM
historicfirearms,

THANKS for the info. = I'll "call around" to some of the smaller/local FBOs and will pass along your comment to our classic outboard "addicts", too..
(My 2-cylinder, 18-40HP "Johnnyrudes" don't do well on ethanol "enhanced" gas AND they need a mixture of 24/1 gas to 2-cycle oil, too.)

yours, tex

km101
04-22-2017, 01:10 PM
You guys in texas should look at your local airport and ask for 100LL, prounounced as "hundred low lead". If they ask tell them its for your ultra lite. It will cost around $5 a gallon. Its great fuel that takes years to degrade. I put it in all my engines that sit for extended time, but dont use it in anything with a catalytic converter. The lead will plug cats up.

Thanks! I will check with the smaller airports in the area. I know of 2-3 that should have it but don't know if they will sell to "off airport" customers. I will try the "ultra-lite" story. ;)

Don't think I would have any success at DFW Int'nl. lol

Petrol & Powder
04-22-2017, 01:32 PM
Octane is not a "burn retardant". It is two things. An 8 Carbon atom molecule, and a burn speed rating based on that molecule.

-HF
True, I think some posters are using the word "Octane" to indicate the Octane rating. That's proper considering the context of this thread but not technically correct. There is a difference between Octane - a class of hydrocarbons and Octane rating - a measure of a fuel's ability to withstand heat & pressure without detonating.

LAKEMASTER
04-22-2017, 01:46 PM
I bought a boat years ago that sat for 7/8 years, maybe more. I ran 3 gallons of 40:1 through it off of a gas can.

Motor was a mid 80s mercury inline 4 cylinder. ( iron duke)

Pulled the spark plugs after the 3 gallons and they were gray. Not black.

Modern day 2 cycle oil is every clean burning and very efficient.

44man
04-23-2017, 08:17 AM
Long ago before synthetics I ran a popular 2 stroke oil and had problems with carbs all the time. I found particles or what looked like paraffin floating in the gas. It plugged everything.