Vintage Chainsaw Fuel Mix

[oliverkid]

Bought a nice original 1961 David Bradly Sears 758G chain saw at an auction this weekend. Went for cheap and always wanted an old saw to play with. Want to try to get it running so have a question on the fuel. Got the manual with the saw and it says .75 pints of oil/gal of gas or 12 fluid ounces. Easy enough. All of our other 2 stroke stuff is Stihl and we run their Stihl Ultra 2 stroke oil. That is a mix ratio of 2.6 fluid ounces per gallon of gas. Crazy how much things have changed. Question is, is it safe to use that Stihl oil in this old saw at the higher mix ratio or is there a different oil that would be better?

 

[tomturkey]

My first chainsaw was a 12 in bar with a Montgomery Wards badge. It was a 16:1 gas oil mix. I cut mountains of firewood to heat this old farmhouse with that saw. I believe the longevity was due to the healthy oil gas mixture. Everything I have now is 50:1. I would never try to run an old saw on gas proportioned for todays machines. jmho ymmv gobble

 

[Pembroke]

I do believe that I would go by the manual. JMHO also

 

[oliverkid]

My first chainsaw was a 12 in bar with a Montgomery Wards badge. It was a 16:1 gas oil mix. I cut mountains of firewood to heat this old farmhouse with that saw. I believe the longevity was due to the healthy oil gas mixture. Everything I have now is 50:1. I would never try to run an old saw on gas proportioned for todays machines. jmho ymmv gobble

Question isn’t about the mix ratio. I want to know if it’s ok to use the Stihl oil or if I need to use something different.

 

[tomturkey]

OK I'll try again, some of the older 2cyl stuff that I could read the label on used motor oil mixed with gas. I always used 2cycl oil mixed with gas that was labeled outboard motor 2cycl oil. When I moved up to saws that are a 50:1 mix, I've always used the 2.6oz bottles of husqvarna 2cycl mix oil. NO I would not use the Stihl 2cycl oil, even at a higher ratio of 12 oz. to the gallon. But again jmho ymmv gobble

 

[oliverkid]

OK I'll try again, some of the older 2cyl stuff that I could read the label on used motor oil mixed with gas. I always used 2cycl oil mixed with gas that was labeled outboard motor 2cycl oil. When I moved up to saws that are a 50:1 mix, I've always used the 2.6oz bottles of husqvarna 2cycl mix oil. NO I would not use the Stihl 2cycl oil, even at a higher ratio of 12 oz. to the gallon. But again jmho ymmv gobble

 

[Country-Boy]

I’d use what the manual says as far as ratio. Modern Stihl 2-stroke oil is not very good. I use Husqvarna oil for 50:1 stuff and Lawn-Boy oil for all other ratios in my vintage chainsaws. Both are good oils.

 

[Blackhole49]

Question isn’t about the mix ratio. I want to know if it’s ok to use the Stihl oil or if I need to use something different.

Interesting how you say it isn't about the mix ratio yet your original question ask about using the higher mix ratio. Yes, you can run the Stihl oil. That mixture is about 10.5 to one. Any oil would probably be safe at that rate. If it were mine, I would use a good quality 2 stroke oil and not mix it any more than 25 to 1. The reason the mix rate was so low was because of the quality of the oil. I have run all my 40+ year old 2 strokes at 40 to 1 even though they are clearly marked at 16 or 25 to 1 and have for years (25+) with no issues . Your saw and your money.

 

[oliverkid]

Yes, you can run the Stihl oil. That mixture is about 10.5 to one. Any oil would probably be safe at that rate. If it were mine, I would use a good quality 2 stroke oil and not mix it any more than 25 to 1. The reason the mix rate was so low was because of the quality of the oil. I have run all my 40+ year old 2 strokes at 40 to 1 even though they are clearly marked at 16 or 25 to 1 and have for years (25+) with no issues . Your saw and your money.

Alright thanks. So if I cut it to about 6 oz/ gal do you think I would still be safe? I figured oil quality had a lot to do with the original high oil content.

 

[old]

Back when my old David Bailey still ran I used the same mix as I did for the Homelite we had and never had any problems with it. What killed the old D/B was a tree that fell up hill and broke the carb off of it

 

[M-MAN]

If it was me I would use 2 of the little bottles of Stihl oil and call it good. If it smokes too much add a tad more gas.That will give you a 25 to 1 ratio. The old 16 to 1's were nasty. Smoked like a freight train and constantly fouled the spark plugs. The 12 oz is referring to motor oil which was usually the cheapest reprossed oil you could buy.

 

[38 Sears Roebuck]

Just my two cents for what it's worth. I have a 30 year old 2 cycle lawn boy mower that I mix 32:1. And other slightly more newer 2 cycle engines with no problems. That ratio seems to work for my equipment. I don't use Stihl oil to mix with just a good quality brand oil.

 

[shaun wallace]

I use auto parts store 2 stroke oil. I use 2 Homelite Super XL auto, run them 35to1 or about. Have newer saw and string trimmer that dont like it that oily so add little gas when filling.

 

[bc]

I think back then they used a different metal for their pistons, rings, and cylinders that needed more oil in the mix. Kinda like an old tractor. Nowadays they use aluminum and chrome stuff. Something to think about.

 

[T in NE]

Bought a nice original 1961 David Bradly Sears 758G chain saw at an auction this weekend. Went for cheap and always wanted an old saw to play with. Want to try to get it running so have a question on the fuel. Got the manual with the saw and it says .75 pints of oil/gal of gas or 12 fluid ounces. Easy enough. All of our other 2 stroke stuff is Stihl and we run their Stihl Ultra 2 stroke oil. That is a mix ratio of 2.6 fluid ounces per gallon of gas. Crazy how much things have changed. Question is, is it safe to use that Stihl oil in this old saw at the higher mix ratio or is there a different oil that would be better?

That's 11:1. Modern 2 stroke oil at that ratio should be safe.

 

[chcase]

Bought a nice original 1961 David Bradly Sears 758G chain saw at an auction this weekend. Went for cheap and always wanted an old saw to play with. Want to try to get it running so have a question on the fuel. Got the manual with the saw and it says .75 pints of oil/gal of gas or 12 fluid ounces. Easy enough. All of our other 2 stroke stuff is Stihl and we run their Stihl Ultra 2 stroke oil. That is a mix ratio of 2.6 fluid ounces per gallon of gas. Crazy how much things have changed. Question is, is it safe to use that Stihl oil in this old saw at the higher mix ratio or is there a different oil that would be better?

Some where still have the old saw of my dads and the gas can that had the oil cup that that was made to be held in the can that had the measure marks on it for oil. The mixing oil we have now days is alot better than then the 1960's 16-1 would now be the mix for my dads old saws.

 

[KL in Wi]

I have had my Homelite saw for over 40 years. The first 20 years it did a pile of work. I don't remember what the book said on oil ratio but, I started using Amsoil at 100-1 ratio. To this day it still runs like a new one. On a real hot day in summer, I would add a little extra oil. I've never had a problem.

 

[Fritz Maurer]

I think back then they used a different metal for their pistons, rings, and cylinders that needed more oil in the mix. Kinda like an old tractor. Nowadays they use aluminum and chrome stuff. Something to think about.

I have had my Homelite saw for over 40 years. The first 20 years it did a pile of work. I don't remember what the book said on oil ratio but, I started using Amsoil at 100-1 ratio. To this day it still runs like a new one. On a real hot day in summer, I would add a little extra oil. I've never had a problem.

This is not the first time I’ve seen this lean of a ratio. I was on a golf cart forum when I first heard of this and I simply didn’t believe it was possible. But they discussed it like it was no big deal, which apparently, it wasn’t.


I have no issues running old two strokes at 50:1 .

 

[DanielW]

I don't think you can do any harm using the Stihl oil at the higher mix ratio for any saw - . The new Stihl and husky oils burn up at a higher temperature, because newer saws and most of their high-revving, air-cooled two strokes run at higher temperatures. But that shouldn't be a problem in your case running it in an older, slower, cooler saw. The real problems you see with oils is when folks run the universal blue/green two-stroke crap in saws. That universal oil is supposedly meant to work in everything from outboards to lawnmowers to chainsaws, but usually burns up at far too low a temperature for modern, high-revving saws. If you read the Stihl manual closely even for newer saws, they give the 50:1 recommendation for Stihl oil (which applies to any proper saw oil), and 20:1 for other oils (like the blue/green junk) for that reason.

Bottom line: No problem using the Stihl oil. I'd be mixing somewhere between a 15:1 and 20:1 for a saw of that era.

 

[KL in Wi]

This is not the first time I’ve seen this lean of a ratio. I was on a golf cart forum when I first heard of this and I simply didn’t believe it was possible. But they discussed it like it was no big deal, which apparently, it wasn’t.


I have no issues running old two strokes at 50:1 .

I forgot to add that with the Amsoil, I ran the Homelite at Amsoil's recommended ratio of 100 to 1. Also used it in my snowmobiles when you had to mix gas and oil.