# Stihl Farm Boss MS271 just stopped

#### johneh

##### Minister of Fire
I use a 2.5 US gal gas can
witch is just short of 10 liters
I add 1 -200ml bottle of Stihl 2 cycle oil
My oldest saw a 026 has run this since new
and it still runs like new It is 28 years old
and cuts between 10 and 20 cord a year
It is my go-to saw out of 3 Stihl saws I own

#### Sodbuster

##### Minister of Fire
That is why I only mix up a gallon at a time. My Stihl oil says to mix with 1 gallon of gasoline, easy peasy. Trying to jump between metric and oz will cause you headaches.

#### johneh

##### Minister of Fire
That is why I only mix up a gallon at a time. My Stihl oil says to mix with 1 gallon of gasoline, easy peasy. Trying to jump between metric and oz will cause you headaches.
Not if you are a Canadian in my age group we were brought up with Metric and Imperial
Going from one to the other is normal for anyone in a trade
ex 60 = 15 10 = 50 0 =32 I can also do inches to cm or parts thereof
In my trades( 3) you have to know both

#### Sodbuster

##### Minister of Fire
Not if you are a Canadian in my age group we were brought up with Metric and Imperial
Going from one to the other is normal for anyone in a trade
ex 60 = 15 10 = 50 0 =32 I can also do inches to cm or parts thereof
In my trades( 3) you have to know both

I'm not in a trade, but was educated in the 70's when the US was going to go metric, but never did, forgive me for not remember details from the 6th grade. We don't sell fuel in in the US by the liter it's by the gallon, my Stihl branded oil sold in the states is labeled in oz per gallon. Why we never went metric is beyond me, but we learned it, but never used it. Unless you are in the medical field, as my wife is, then everything is metric, go figure.
Oh, and when I was working we had to convert almost everything, because the machines we serviced that made boxes were almost all European made.

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#### maple1

##### Minister of Fire
I use a 5l jug for mix. I dump half a bottle of oil in (100ml) and fill it up not quite full. Around 4.5l. Gives me 45:1. Never any oiling issues, things keep working like they're supposed to.

#### PaulOinMA

##### Minister of Fire
My education was in chemistry. Temperatures are in C, but you always want to know the F equivalent since it is what you grew up with. Was always converting rough estimates in my head.

C = 5/9 (F -32)

F = 9/5C + 32.

#### brenndatomu

##### Minister of Fire
Math is not my strong suit so how much fuel to add to a 2.6 oz bottle of oil?
For what ratio?
Obviously 50:1 is 1 bottle with 1 gallon...40:1 would be 1 bottle with .8 gallons gas

#### Sodbuster

##### Minister of Fire
For what ratio?
Obviously 50:1 is 1 bottle with 1 gallon...40:1 would be 1 bottle with .8 gallons gas

Thank you, I think I'll try the 40:1 even though I have no problems. I am always uncertain of the gas pump giving an exactly accurate measurement at 1 gallon, even though they are supposed to.

brenndatomu

#### salecker

##### Minister of Fire
Run what the manufacturer calls for any high quality 2 stroke oil will do, Stihl, Husqvarna etc. Don't cheap out on oil.

OK, I'm always willing to be educated, I have no doubt the 50:1 ratio came straight from the EPA. I bought a Stihl MS 261, it's not even broke in yet. It was a lot of money for me, but I wanted a good saw, that I wasn't constantly wrenching on vs cutting. How rich do saw porters recommend? Math is not my strong suit so how much fuel to add to a 2.6 oz bottle of oil?
i run 32;1 oil in everything.New saws,ported saws old saws and Antique saws.
so for a 2.6 oz bottle of oil add 83.2 oz of gas(just used the calculator on my phone)which is 1.53846154 of a US gallon.
With pretty much everyone using a smart phone these days you always have a calculator with you so mixing is a breeze

#### brenndatomu

##### Minister of Fire
so for a 2.6 oz bottle of oil add 83.2 oz of gas(just used the calculator on my phone)which is 1.53846154 of a US gallon.
I think you divided instead of multiplied...or something...32:1 with 2.6 oz oil would be ~.65 gallons of gas...
EDIT: 0.65 gallons is 83.2 oz as you stated...so what is the 1.53846154 gallons that you mention? I so cornfused now...

sloeffle

##### Feeling the Heat
• For a 50:1 ratio of gas to oil, use 2.6 fluid ounces of oil per gallon of gas.
• For a 40:1 mixture, use 3.2 fluid ounces of oil per gallon of gas.
• For a 32:1 mixture, use 4 fluid ounces of oil per gallon of gas.
Most of those small oil bottles are 3.2 fl oz so you'll have to add a bit for 4 fl oz.
I also always run 32/1 because I like my stuff to be well lubricated and last a long, long time. Almost never smokes either.

#### Sodbuster

##### Minister of Fire
• For a 50:1 ratio of gas to oil, use 2.6 fluid ounces of oil per gallon of gas.
• For a 40:1 mixture, use 3.2 fluid ounces of oil per gallon of gas.
• For a 32:1 mixture, use 4 fluid ounces of oil per gallon of gas.
Most of those small oil bottles are 3.2 fl oz so you'll have to add a bit for 4 fl oz.
I also always run 32/1 because I like my stuff to be well lubricated and last a long, long time. Almost never smokes either.

Actually the small ones are 2.6 oz and the larger ones are 12.8 for 5 gallons (50:1)

##### Feeling the Heat
Actually the small ones are 2.6 oz and the larger ones are 12.8 for 5 gallons (50:1)
My last several bottles had a fill cup at 3.2 oz. Looks like this, but different brand.

#### brenndatomu

##### Minister of Fire
My last several bottles had a fill cup at 3.2 oz. Looks like this, but different brand.
They are just making it easy to mix 40:1/gallon...

#### Alpine1

##### Feeling the Heat
LOL... I’m glad we use the metric system here:
2% oil mix is 200 ml to 10 liters (9.8 liters to be exact)
3% oil mix is 300
You can easily make 3.725% if you need to, and have a graduation fine enough on your gas tank

johneh

#### ikeepgrnbarsfull

##### New Member
I do fancy myself mechanically inclined. I used to drive a 30 year old diesel S-Class daily and there was always something to wrench on.

What advice or links can you point me towards to start cleaning this transfer out?

In the meantime, I picked up an MS261 and it rips. I'm absolutely going to run the right fuel in it and probably around 45:1 just to be safe.

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#### Sodbuster

##### Minister of Fire
I do fancy myself mechanically inclined. I used to drive a 30 year old diesel S-Class daily and there was always something to wrench on.

What advice or links can you point me towards to start cleaning this transfer out?

In the meantime, I picked up an MS261 and it rips. I'm absolutely going to run the right fuel in it and probably around 45:1 just to be safe.

Have the same saw and love it, it's a screamer, and not even completely broken it yet. Full chisel chain and the chips are flying.

#### salecker

##### Minister of Fire
I think you divided instead of multiplied...or something...32:1 with 2.6 oz oil would be ~.65 gallons of gas...
EDIT: 0.65 gallons is 83.2 oz as you stated...so what is the 1.53846154 gallons that you mention? I so cornfused now...
Yea i know it's confusing,US Gallons, Liters ,Canadien Gallons are all different...
But ounces are all the same...
Using the calculator again who knows where the 1.53846154 comes from
So double check before you commit.

brenndatomu

#### salecker

##### Minister of Fire
I do fancy myself mechanically inclined. I used to drive a 30 year old diesel S-Class daily and there was always something to wrench on.

What advice or links can you point me towards to start cleaning this transfer out?

In the meantime, I picked up an MS261 and it rips. I'm absolutely going to run the right fuel in it and probably around 45:1 just to be safe.
The best way to clean the transfer off is with a mandrel on a drill or..and sandpaper.
The plating is supper hard so the sandpaper will not damage it,but you have to watch around the port openings.If you were to concentrate on one spot for a lengthy time you may damage the plating.
There is a website Outdoor Power Equipment,look up Masterminds cylinder cleaning thread.
He has a video to watch as well.

#### brenndatomu

##### Minister of Fire
The best way to clean the transfer off is with a mandrel on a drill or..and sandpaper.
Muriatic acid is the way we did it when I worked at the bike shop and was trying to save a pricey chrome cylinder for someone. A few drops on the aluminum and it will wipe off...may take a few cycles to get clean. BE CAREFUL, you are working with acid...all safety rules need to apply!

#### Sodbuster

##### Minister of Fire
Muriatic acid is the way we did it when I worked at the bike shop and was trying to save a pricey chrome cylinder for someone. A few drops on the aluminum and it will wipe off...may take a few cycles to get clean. BE CAREFUL, you are working with acid...all safety rules need to apply!

I have no idea if this works, but if brenndatomu say's it does I believe him. Just be warned, as he said Muriatic acid is wicked to the nostrils and lungs. When you open the bottle, you'll actually see "vapor" coming out of the bottle. Keep the bottle as far from you as possible and do not breath in. Eye's and gloves are a must. I used to work in a meat processing plant, and we'd use muriatic acid to de-lime the equipment. Worked great.

#### ben94122

##### Burning Hunk
Yea i know it's confusing,US Gallons, Liters ,Canadien Gallons are all different...
But ounces are all the same...
Using the calculator again who knows where the 1.53846154 comes from
So double check before you commit.
It's the reciprocal:
1/1.538 = 0.65
Meaning you have the units upside down someplace. Write the equation out with units next to each number, and make sure each element of the equation is flipped the right way so you end up with the units you want,

Just be careful, because it is a slippery slope from this to dimensional analysis, which is truly the language of the gods.

#### salecker

##### Minister of Fire
Muriatic acid is the way we did it when I worked at the bike shop and was trying to save a pricey chrome cylinder for someone. A few drops on the aluminum and it will wipe off...may take a few cycles to get clean. BE CAREFUL, you are working with acid...all safety rules need to apply!
The problem with acid is if you have a flaw in the plating you will lift it with acid, ruining the cylinder.
If you know what you are doing with acid you can be careful and be fine.But the chances of destroying the cylinder are quite a bit higher,and add some percentage to that if you have never cleaned a cylinder with acid.
After i saw Masterminds way i got rid of my acid,less chance of destroying valuable parts.Once you get into bigger saws the cylinders can cost \$300 or more.
Not going to risk that kind of money if the cylinder has a flaw that you don't see,and have the plating lift.You can run a cylinder with a flaw so long as the plating is sound.
So your choice on the method,how good are you at predicting the level of damage under the aluminum transfer is up to you.If there is a flaw you will not see it till the plating begins to lift.

#### brenndatomu

##### Minister of Fire
The problem with acid is if you have a flaw in the plating you will lift it with acid, ruining the cylinder.
If you know what you are doing with acid you can be careful and be fine.But the chances of destroying the cylinder are quite a bit higher,and add some percentage to that if you have never cleaned a cylinder with acid.
After i saw Masterminds way i got rid of my acid,less chance of destroying valuable parts.Once you get into bigger saws the cylinders can cost \$300 or more.
Not going to risk that kind of money if the cylinder has a flaw that you don't see,and have the plating lift.You can run a cylinder with a flaw so long as the plating is sound.
So your choice on the method,how good are you at predicting the level of damage under the aluminum transfer is up to you.If there is a flaw you will not see it till the plating begins to lift.
I hear ya...never had one lift on me personally...and as far as running something with a flaw, kinda hard for a shop to charge for and stand behind a rebuild with something like that, unless the customer signs off on doing it. We usually recommended getting it re-sleeved if it wasn't "perfect" after acid removal...not an option on everything though I know...

##### Minister of Fire
I run my 2 strokes all a little heavy on oil as well. 42:1, Klotz with ethanol free 93 octane, gives it that nice racing fuel smell too. Never a problem.

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