Fuel question

[Rudy M.]

Got 2 new saws--Stihl MS210 and MS310. I dumped a 2.5 gal oil bottle of Stihl oil into a gas can told my son to go get 2.5 gallons of gas. He got regular. Our regular is 87 octane. Then I read the back of the bottle that stated use 89 octane. Then I read the manual and it stated to use 89 octane. Will the 87 octane hurt the saws? Should I go get 2.5 gallons of 93 octane and mix up more gas and mix the two cans in a 5 gallon can? I'm not sure I am going to be able to use up that much 50:1 gas in the next couple of months.

Can I use this in my boat--1990 25hp Merc (it takes 50:1 mix). But the Stihl oil is for "air cooled" engines and the boat is water cooled. Seems I read somewhere you can use oil designated for air cooled engines in anything, but you shouldn't use oil designated for liquid cooled engines in air cooled engines.

 

[PA Plumber]

If the warranty depends on 89, then I would use 89 in the saw. I used to dump my unused 50:1 mix into my work van when the tank was fairly full.

That said, I used to run 87 in my saws until I joined this site a few months ago.

 

[ShoerFast]

Turn the "H" jets out and run it fat.

If your a good carb tuner, or have a tach, just running a fatter ratio will lot not harm the engines just being off by a couple points in octane. By fat I am thinking that if you usally tune by ear "just in" from a too-rich burble , tune it to a slight burble. Or if you set with a tach just set it about 500-750RPM
's fatter then normal,<fatter, or richer runs slower>,,,,,, also not a bad idea in hot weather anyway.

 

[fishhuntcutwood]

You're correct on your thoughts on air cooled vs. water cooled, but why mess with it? Just dump it in your car.

That said, I know a guy who's been running outboard oil through his saws the past three years that he recalls....no troubles yet, though I can't recommend it.

 

[Fiore Indiana]

I believe the Stihl manual says use only fresh gas up to 60 days old. I use a one gallon container that way I go through it more often.

 

[Rudy M.]

OK--thanks for the tips. Both saws I have are brand new--about a tank full of whatever gas the shop put in them through each saw. I went safe and simply mixed up another 2.5 gallons of 93 octane and blended it with the 87 so now I have 90 octane.

I always ran 87 octane in the old saws and they seemed to work fine, but ran them at 32:1. This 2 stroke stuff is getting to be a pain--I think the weed wacker likes 16:1, the Lawnboy and the old saws get 32:1, all regular 87 octane, and the new saws get 89 octane and 50:1, the YZ85 gets 32:1 and 93 octane, and the YZ and WR 250Fs get 93 octane straight gas! Oh--and the wheeler gets 87 octane straight gas and the tractor takes deisel fuel.

I should be living at a gas station!

 

[BostonBull]

Oh boy. Just mix everything 50:1 with 93 octane.

Please not anohter oil mixture thread............PLEASE!!!!!!!!!!!!:bang:

 

[ThinkFast]

This 2 stroke stuff is getting to be a pain--I think the weed wacker likes 16:1, the Lawnboy and the old saws get 32:1, all regular 87 octane, and the new saws get 89 octane and 50:1, the YZ85 gets 32:1 and 93 octane, and the YZ and WR 250Fs get 93 octane straight gas! Oh--and the wheeler gets 87 octane straight gas and the tractor takes deisel fuel.

I should be living at a gas station!

I couldn't agree more. I always go with higher octane as the price isn't that big of a deal on these machines that you don't run as many gallons through. And yeah I have run a few things rich just to avoid having yet another mix sitting around.

If in doubt I throw it in my car.

 

[computeruser]

It's hell having choices.

 

[redprospector]

I run 87 octane at 32:1 in everything that's not modified. It hasn't hurt anything I own in years of use.

Andy

 

[OilHead]

Wow 93 Octane .We dont see that here on the west coast. If it was me I'd buy the 93 & mix it at 40/1 .

 

[Mr. Firewood]

Wow 93 Octane .We dont see that here on the west coast. If it was me I'd buy the 93 & mix it at 40/1 .

wow, sucks for you guys, I can get up to 112 at the pump here in N.W. Ohio, 94 is the highest most stations but there are a few that have 100 UL and 112 leaded

 

[ShoerFast]

It's hell having choices.

Here is something else for a think.

As silly as it may seem to split a couple points in octane, just by your picture, someone is pumping the cheap-stuff, if the next guy thinks that there going to squeeze out a gallon of "premium" there wrong anyways.

Inside that pump, the button you select will draw from the tank it is plumbed to,,,,, but the gas you select still has to purge whatever the last guy was pumping, all the way to the nozzle,,,,,IWO: there is an easy half gallon of cheap stuff anyways.

There are pumps with seprate nozzles for each grade, but what grade really is it?

That dose not even mention how close the refinery is in hitting a good "grade" or "rating" what tank the transport driver dumped what into, there is no way to tell what your really getting. Who makes sure that 85 is not dumped into the 91 tank?

Running fat mixtures in the summer is the best insurance by far over depending on what quality fuel your buying and burning.

I would bet a Dr Pepper that a fat 85 fuel would run cooler then a shy mixture of 87 , and way cooler then a lean 91 ?

 

[OilHead]

I just remember at 13 years old getting gas at the chevron station we allways ran high test it was light blue in color. Ran it in our 4 cycle mini bikes and go carts. .23 cents a gallon . Also ran the same stuff when it came to the Mac 45 & Mac 101 mac oil at 25-1 as I recall. Never toasted anything and we beat the hell out of them most of the time.

 

[OilHead]

There is one way of getting around the octane issue buy adding about 1/4 of a shot glass of octane booster per gallon. Detonation pinging is useally only an issue on hot days or if you really taxing your equipment. I'm not concerned with saving a few cents at the pump besides youll get better mileage with the good stuff.

 

[Haywire Haywood]

Aren't most octane boosters using ethanol? I saw a bottle of some kind of gas treatment that boasted ethanol as it's main ingredient on display right next to the 2 stroke mix and chains... as if they were marketing it to chainsaw users.. this was at Lowes.

Ian

 

[vapnut257]

I dumped a 2.5 gal oil bottle of Stihl oil into a gas can told my son to go get 2.5 gallons of gas.

Am I miss reading something or did he put too much oil
(2.5 gal of Stihl oil)with 2.5 gal of gas?

 

[PA Plumber]

Am I miss reading something or did he put too much oil
(2.5 gal of Stihl oil)with 2.5 gal of gas?

Ooooohhhhhh, so that's why I have to buy sparkplugs by the case and clean my spark arrestor every 3 minutes.


I'm pretty sure he was using the small bottle that requires 2 1/2 gallons of fuel to end up with 50:1 mix.

 

[goof008]

I though all the new saws ran the 1:1 ratio!?!? I agree with PA, I think he had the "add one bottle to 2 1/2 gallons of gas" oil.

 

[OilHead]

Reports I have indicate fuel can lose up 1 octane point per week depending on heat & so on. Remember gas is just oil that is cracked into gas. Here petrol is pumped underground to a central point. Then each company taps off all the same stuff & put in there super carbon remover valve cleaner stuff thats really just detergants found in ATF automatic transmission fluid ,octane & so on maybe even some corn . So when you get you r gas I cant reccomend your taking new your MS660 with restrictave exhaust heat causing muffler with clogged screen running lean & taxing it w/ a long bar on a hot day without some additional top notch oil / & not at 50/1. LOL:deadhorse: