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I use a 50:1 mixture with Stihl synthetic oil for the rest of my 2 stroke equipment is this ok for my lawnboy?

Thanks

I used synthetic Amsoil @ 50:1 with no problems, so you should be fine.

Thanks. I thought it would be ok just wanted to be sure.

E Behm said:

I use a 50:1 mixture with Stihl synthetic oil for the rest of my 2 stroke equipment is this ok for my lawnboy?

Thanks

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I also use the Stihl Ultra at 50:1 with all of my chainsaws and my LB's no matter what the age. There are purists who do not believe in this, but its just what I do. I have never fried a piston with Stihl Ultra.

I also run 50:1 with Poulan 2-stroke oil. No problems after many hours over the last few years (including both D- and F-series engines).

One thing to bear in mind is that the technology of these lubricants has advanced a lot in the last couple of decades. I'll bet that, if the 2-stroke gurus at LB were writing user manuals today, they'd recommend 50:1.

Well I will put my 2 cents in on this subject. First off I have been around two strokes for quite some time most of that with snowmobiles. All snowmobiles have been oil injected since the 80's unless they are a race machine or modified by the owner. Most of modern snowmobiles run 50 to 1 with skidoo being the exception with some of the rotax engines. The ratio is based on the engine internals (crank and connecting rod bearings). I run all my two stroke lawn boys at 32 to 1 which is the oem recommendation. I use Blue Marble that is basically vegetable oil base with additives (I use it all my sleds for the last 10 years, have in gallon jugs just easier than getting cheaper 2-stroke oil for the lawn boy). The reason why I use BM in sleds is how it does not gum up the exhaust power valves. I have not cleaned a power valve since I switch to BM where before that it was every year. I figure the BM will eliminate the clogging of exhaust ports that can develop in small 2-stroke engines. Another fact about 2-stoke engines and oil is that the oil is always fresh going through the motor. So really there is little benefits to synthetic in a 2-stroke other than not gumming up the exhaust. To each his own on the synthetic, certainly the oil is quality and will work very well.

As far as 32 to 1 or not in a lawn boy. A tech told me that 32 to 1 will cool motor more than other ratios. LB are fan cooled or air cooled so the temp will rise with different environmental conditions. Also the connection rod and crank bearings are designed for 32 to 1. I have 2 LB one durafoce and one M-series. The duraforce is the last of LB 2-strokes. There was synthetic oil available when this motor was developed as well as high quality regular 2-stroke oil. My point is there is a reason why the engineers chose 32 to 1. I read in another forum from 2009 how some mowing contractor could not keep a dura force together for a season, the fact is he was running 75 to 1 full synthetic so the exhaust would stay clean of course it was the mowers fault. The M-series is oil injected at 64 to 1. The engine is the last of the OMC designed 2-strokes. I still use the injection system as its a proven system driven off the crank shaft with a gear, very similar to what has been on snowmobile engines since the 70's. Blue marble is not cheap (40.00 per gallon), I use to try an find a dealer now I just use Amazon as you can get it with no shipping cost usually.

http://www.amazon.com/Blue-Marble-2...id=1464619097&sr=8-1&keywords=blue+marble+oil

I am a firm believer in using Lawn Boy brand oil at 32:1 in Lawn Boys and Stihl brand oil 50:1 in Stihls that's what they were designed to run on and I have had no issues with mine however I have repaired several mowers where the owners used cheap o oil and the exhaust ports were clogged at lest they were using oil I guess
I'm sure 50:1 would work but it's not getting as much oil so IMO I would stick with 32:1

Hi,

I used to uses Lawn-boy oil when it was available at 32:1. I now use Valvoline multi-purpose 2 stroke oil, TCW-3 rated. Seems to me I recall an ultra-light airplane manufacturer did a test of 10 Rotax ultra-light engines using various oils and ran them for a ton of hours, they concluded after tear down, Lawn-boy oil was the best.

Jeff

jp1961 said:

Hi,

I used to uses Lawn-boy oil when it was available at 32:1. I now use Valvoline multi-purpose 2 stroke oil, TCW-3 rated. Seems to me I recall an ultra-light airplane manufacturer did a test of 10 Rotax ultra-light engines using various oils and ran them for a ton of hours, they concluded after tear down, Lawn-boy oil was the best.

Jeff

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My local ACE hardware franchise carries genuine LawnBoy 2-cycle oil in both 8 oz and 4 oz bottles (to treat 2 and 1 gallons respectively). Surely you can get LawnBoy oil.

Always a vexed question.
FWIW I use canola, bought from the supermarket mixed 40:1 in all my personnal 2 stroke gear, including what I lend out to customers while I repair their gear.
No problems to date.
For customers engines I run Stens 2 stroke at 50:1 in all of them and advise the customers to do the same.
The old days of 25:1 , 30:1 etc was based on a totally different formulation using oils that did not mix very well in fuel.
Some of the older engine ratios were for engine oil.
It is not odd for some one to come in with a fried engine that they have run one or more tanks of strait fuel through them by mistake.
When the EPA exhaust regulations came in down here, magically we can now run Sthils o 100:1 ( only using their magic snake oil )
Victa suddenly decided that their 30:1 mowers could run 50:1 again only if you use their magic ( snake) oil .

Marketing managers have a lot to answer for as they decided you lot are so bone stupid you could not cope with their brand changing the fuel mix so if they were 20:1 in 1950 they kept them at 20:1 till 2010

The bottom line is, if you run what the manufacturer recommends, you won't throw a rod, or seize-up the engine. Look thru your exhaust port, you got 3-rings on your piston run 16-1 ratio, you got 2-rings on your piston run 32-1 ratio, any brand of 2-cycle oil you please, I prefer LawnBoy brand, and I add a dollop of Marvel Mystery Oil to my 2-gallon mix also. I'm speaking exclusively of LawnBoy 2-cycle engines here.