oil ratio ?'s

[woodpecker]

I recently purchesed a ms360 pro and the fuel mixture is 50:1. I also have a old 032av I use for limbing the fuel mixture is 40:1. My stihl dealer said if I'm useing the new stihl oil I could run the 032 at 50:1 this would be nice because I'd only need one gas can. Don't want to try this until I get a second opion. Please help me! or would I be able to run the 360 at 40:1 without fouling plugs. I'm not a tech. just an operater.

 

[don]

Why not go the other way

Run everything at 32:1

Better lubricants today so can use 50:1 but 32:1 MIGHT make it last longer.

This is a very in debt debate debated dozens of time here.

 

[woodpecker]

so if I use the 40:1 mix I use in my 032 it would be better but not as good as 32:1, so If I have the 50:1 bottles that I got free with the new 360 (a 6 pack) how much gas do i put with it to make 40:1 instead. and should I have the dealer readjust the carb for this mixture?

 

[rahtreelimbs]

Here we go again!!!

 

[woodpecker]

sorry, I don't want to get it started but I did the search and can't find the answer i'm looking for 40:1 how much gas do i mix with the little orange stihl bottle for 1 gal. mix for 50:1 ?

 

[glens]

(40÷50)×1gal=0.8gal gas per bottle

Since the mixture is expected to be 50/51 [98.04%] gasoline and it will instead be 40/41 [97.56%] it will be 0.49% [one half of one percent] too lean.  Probably not enough to worry about on a brand new saw which is set a little rich anyway for breaking in.  Probably not enough to worry about on a saw which is not already too lean otherwise.

 

[stihltech]

oil

Go to any saw shop and see how many different ratios they mix. Then find out how many saws they have lost on it.

I even use Stihl 50:1 in my 1974 John Deere snowmobile. No problem at all.

 

[tony marks]

well ive gone to stihl 45-1 . but only because ive set my saws at their max allowable rpm ,and i just want to make sure. i run about 5-6 different types 2 stroke engines and not much trouble out of any ,in the last couple of yrs,on stihl 50-1.
not long ago i had a 25 cc craftsman
finally give it up. its homeowner version and lasted 3 yrs of daily use..
guess i should add that the 25 cc that poulan put out ,was one of the better motors ive seen. lotto power and holds up well.

 

[ricksvar]

woodpecker,
Here's how I figure ratios with 128 fluid ounces in a US gallon:

50:1(50 ounces gas/1 ounce oil)128 divided by 50=2.56 ounces oil per gallon.
40:1,128 divided by 40=3.2 ounces oil per gallon.
32:1,128 divided by 32=4 ounces oil per gallon.

Rick

 

[Stumper]

Tony, was that Poulan 25ccs or a Poulan XXV? The PXXV wasn't a 25cc saw---34ccs if memory serves. Good old saws.

32/1----40/1 on everything. That isn't oil- rich enough to cause fouling problems but leaves a nice margin for error.

 

[tony marks]

stumper . no im talkin craftsman 25 cc ,used on blowers an trimmers.
ive found this particular motor to be
dependable an troble free. at least in the past.; they ll probably mess it up somehow. never seen it fail yet.
not an endorsement of poulan.just this motor. by the way i just traded a good little xxv saw. pretty good but made before poulan was bought by that big company.

 

[z4lunch]

Synthetic!!!

Steve here...
32/1 synthetic!!! Run 50/1 petrol base and look at your piston, I'll just bet... it's dry as a bone.
My 2 cents
Steve

 

[z4lunch]

New 025

Steve here...
Here is a pic of the cylinder of a brand new 025 with one tank of 50/1 oil through it. Yes I warmed it up...
Steve