How To Mix Modern Chain Saw Gas

[Cofe]

Ok there are a lot of different mixes out there for chain saws. 'Why'... I do not know why. I am trying to figure out a satisfactory mix for all my modern saws. A Sthil MS290 calls for a 50/1mix. My other saws call for a 32/1 mix. And a new Chinese made saw I am checking out, calls for a 25/1 mix.
At the present, I am using a 32/1 synthetic mix in everything, even weed eaters. Is there a best mix scenario?

Also the Sthil manual says to use 89 or better octane. Anything lower will cause overheating and piston failure.

 

[foodfisher]

Re: How To Mix Modern Chain Saw Gas

Welll... I recommend you follow manufacturers directions.

 

[Fireman431]

Re: How To Mix Modern Chain Saw Gas

I don't think you're going to find one perfect mix for all of them. That's a big gap. 25:1 is twice the oil of 50:1, and you run the risk of either burning up an engine or fouling plugs. I run all of mine at 40:1 without issue, but I don't beat the crap out of them (weed eater, chainsaw, gas blower). In more important items (O/B engine, SeaDoo) they get what the manufacturer calls for. Those are too expensive to replace and may leave me sitting out in the middle of the lake without a ride home.

 

[Bubbles Up]

Re: How To Mix Modern Chain Saw Gas

Being a stihl head my self , I run all my saw on premium fuel so I don't kill them with ethanol.
I ALWAYS rum then at 50:1 on Stihl premium(made by Castrol) oil for the first few tanks for the break in then they get moved to Stihl Ultra synthetic. I run a couple stock saws the rest of mine get ported and modified.

 

[dwco5051]

Re: How To Mix Modern Chain Saw Gas

Have to agree with all the posters. I run different mixes for my saws and other power tools. If I was only to one keep one mixture around it would be the 50:1 for my saws. The saws cost $500 and up, the weed eaters and leaf blowers I use around the property less than $100. If I am going to ruin one or the other you know which one it will be. I also will not keep mixed fuel for the saws for more than one month. If it isn't used by then it goes into one of the other tools or one of the tractors. A gallon or so of mixed fuel added to the tank seems to make no difference at all in how a fifty plus year old tractor runs. Also only use 89 octane fuel per advice of the Husky factory tech.

 

[j_martin]

Re: How To Mix Modern Chain Saw Gas

The oil mix ratio is a function of engine design. If I mix TC100 oil for my 1950's Graham Paige rototiller, it's mixed at 16:1.

Many mechanics make a good living rebuilding engines that are wrecked because some oil manufacturers of very overpriced oil claim you can mix their oil thinner with good results.

 

[dolluper]

Re: How To Mix Modern Chain Saw Gas

I always throw in extra oil no mater what the mix...keeps the bugs away also....most important is to READ THE LABEL on your oil bottle to how many oz's to mix to achive the mixture ratio as all oil manufacters are different....and follow gas reconmends is the best to do since they spent the money to research the best for their product You can always keep gas unmixed measure your tools gas tank to see how much oil to add and mix it in the tools tank fresh gas just add the oil

 

[RogersJetboat454]

Re: How To Mix Modern Chain Saw Gas

Being a stihl head my self , I run all my saw on premium fuel so I don't kill them with ethanol.
I ALWAYS rum then at 50:1 on Stihl premium(made by Castrol) oil for the first few tanks for the break in then they get moved to Stihl Ultra synthetic. I run a couple stock saws the rest of mine get ported and modified.

Don't know if Canada is any different, but every grade of fuel in the states still gets you the dreaded ethanol (unless marked otherwise).

 

[dolluper]

Re: How To Mix Modern Chain Saw Gas

We have at least 10% ethanol added here

 

[oldjeep]

Re: How To Mix Modern Chain Saw Gas

Luckily all my non injected stuff is 50:1, running on 10% ethanol I just use some generic 2 stroke oil and havn't had any issues with my saws or weedwacker. I do tend to err on the side of more oil.
As for the ethanol argument - if you are running 10% ethanol, make sure you richen up your mixture. The only reason that ethanol gas damages so many 2 strokes is that people leave their mixture at the factory setting which will cause the motor to run lean on ethanol gas.

 

[WIMUSKY]

Re: How To Mix Modern Chain Saw Gas

I too run 50:1 in my Jonsered saw and Stihl backpack leaf blower along with premium gas(which seems to be recommended for small engines)...

 

[puddle jumper]

Re: How To Mix Modern Chain Saw Gas

Don't know if Canada is any different, but every grade of fuel in the states still gets you the dreaded ethanol (unless marked otherwise).

If you look for it you can find ethanol free but rare.

 

[oldskool7_11]

Re: How To Mix Modern Chain Saw Gas

here is a website that lists stations with pure gas
http://pure-gas.org/index.jsp