Small Engines (Lawn Mowers, etc.): Chainsaw fuel mix ratio, synthetic motor oil, two stroke engines


Question
I have refurbished a 1972 Mini-Mac 1 chain saw.  The saw has not been used in some time.  As I recall the fuel/oil ratio was 40:1 with Mcculloch oil.  May I run this saw using Stihl oil at 50:1 without causing any problems?  (my other saw is a Stihl).  I would prefer not to make a separate mix (the saws generally get light use) but don't want to damage the old Mcculloch with improper mix.  Thank you very much.

Answer
Hello David:

>>Yes, the 50:1 ratio Oil Mix should Not Harm the Old McCulloch Saw.
>>All Two Stroke Engines will use a 50 to 1 Ratio using Today's Two Stroke Oils. I once had an Old Chainsaw probably from the 1960s, maybe Earlier 70s that had a sticker on it that said to use a 25 to 1 Fuel/Oil Ratio, but that would have been using Two Stroke Oils of the Time Period the Chainsaw was Manufactured. I was having a Problem with Oil Coming Out of the Muffler and Started Decreasing the Oil in the Gas. I Reduced the Oil Until it was a t a 45:1 Ratio and Decided to be Safe, I would Use a 40:1 Ratio Mix. In that Chainsaw I used 50 to 1 Ratio with no problems.  Today's Two Stroke Oils compared to Yesteryears are more Efficient at Lubricating.  It is like comparing Today's Synthetic Motor Oil to Motor Oils of Decades ago.  All the Equipment I use in Landscaping, anything from a Weed Eater, Leaf Blower, Chainsaw, Hedge Trimmer, use 40 to 1 ratio, and I use all types of makes and models, Stihl, Homelite, Husqvarna, Shindaiwa, and Echo, Sears.  I mix up a 5 Gallon Fuel can and use it in all of the Equipment for my Customers and for my Landscaping. I like my Fuel/Oil Ratio a Little Heavy, so I use a 40:1 Ratio. The Following was Copied and Pasted here from and MTD E-mail to me when I Asked for the OEMs Suggested Mixture for this Unit. The mixture, as described by the engine manufacturer, is a 50:1 ratio when using the approved types of 2-cycle engine oils.
>>50:1 ratio is a mix consisting of 2.5 ounces of 2-cycle oil per 1 gallon of gasoline.
>>The 2-cycle oil used should be approved and have one or more of the following specification titles: NMMA TC-WII, TC-W3, JASO FB, or JASO FC. NOTE: If unsure of the 2-cycle oil specifications, or the oil is not approved, use a 32:1 fuel to oil ratio. This ratio consists of 4 ounces of oil per one gallon of fuel.
>>NOTE:  Always mix 2-cycle fuel oil and fuel in an approved gasoline safe container prior to filling the engine. Make sure to use a separate gas can for this 2-cycle fuel mixture and label it accordingly. Keep in mind that the fuel capacity of these engines normally is less than a gallon, therefore you will have to use this extra oil mixture for multiple fuel fills. Adding a fuel stabilizer will also help to increase the shelf life of fuel.
>>If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Be Safe and Happy. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 5 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John