I associate with engineers who work for companies that make this type of equipment. They have been telling me for a number of years that if one would double the oil in a mix, the engine would never wear out. I use a 20:1 in all my equipment, including chain saws. Works for me and I see no more smoke. I use good 2 cycle outboard engine oil. If it is good enough for $4,000 outboard engines then it is good for my 2 cycle engines. I have been doing this for 30 years.

If you are using "good 2 cycle outboard engine oil" in an air cooled 2 stroke. You are not and will not get double the life out of the engine. The stuff is formulated for water cooled engines that run at a much lower temps.

Echoman
You will have no problems running a 40:1 mix in your F engine. That is all I use for all of my two stroke lawn equipment. I run Chainsaws, trimmers, Lawnboy D,F and New DuraForce engines and had no problems.

Do not know what brand you plan to use. But I use Maxima 927 Caster. It does give off a "racing Fuel" smell and does drool out the exhaust on the trimmers more than I like. But it is great oil.

Thanks for the comments Hippy. I figured all would be fine since I'm using a high quality race proven synthetic made by Torco. I have an older Craftsturd Ryobi my brother gave me new several years ago, and when I used to run Pennzoil multi purpose, every now and then when I least expected it, I'd get a nice HOT drop of oil from the exhaust down the back of my calf! Damn that stings! First time it hit me, I thought I got nailed by a bee! This was running a 40:1 as manu calls for. When I switched to Torco's (at the time) Power Stroke Formula, that condition ended immediately. I'm actually stepping it up a notch and will be mixing their GP-7 full synthetic for my Lawn Boys, trimmers, saws and blowers. You hear the old wives tails not to break any engine either 2 or 4 cycle using synthetic lubes, but until I see or hear of a known fact to prove why you shouldn't, then I'm going to break in all of my new engines or rebuilds using the GP-7 @ 40:1. Anybody else have anything to say about it?

I had no idea there was such a big difference in 2-stroke oils. I usually used the marine grade stuff, I just bought whatever.

Actually blacknumber, by today's standards in oils, there is a big difference. I've reaserached some and spoke with a few different tech from companies that produce "specialty oils" not big oil companies Like Texaco, Pennzoil, etc. Petroleum oils even "low ash" oils since they're naturally formed with carbon base stocks, will all tend to burn with more residuals and leave some deposits with continual use. Not saying they won't adequately lube a slower running 2 stroke like a LB or a cooler running engine like an outboard, but for air cooled high revving 2's is where full synthetics "shine" the most with their custom blended stocks that will hold up to high shearing and heat with a stronger film strenght hence the reason most all synthetics will allow for leaner mix ratios, yet provide the same or more often, better engine protection and will leave the piston crowns, rings and ports MUCH cleaner after many hours than the petroleum based counterparts. I just like using top quality oils in every engine I own. Cost is not a factor to me, luckily. If it's the best, or can be proven to be through actual field results, then I want to use it. Kind of "overkill" with me I guess.

Hippy, I don't know how you have become such an expert on so many different subjects. The combustion chamber temperature on a water cool engine and an air cool engine are approximately the same. I told you that I have been doing this for 30 years. I have never never had a failure on any of the two stroke engines used in my moderate size company with many of these engines running daily, that was traced to the oil mixture. What you say just is not so.

I know, if it is not exotic oil, then it is no good.

Right now I only own one two-stroker, a crapply little McCullough trimmer. I still have half a gallon of mixed gas to use up from last year. When I need more oil or if I get a new piece of equipment I will look into the full synthetics.

I'm not saying that regular petroleum base oil is bad or will wear and engine quicker, heck for the average user even many commercial users, that oil will give good equipment life. What I am saying is that by running synthetics, you will notice your engine will run much cleaner, emit very low or even no smoke with the proper fuel mix ratio and engine tuning.It will also help eliminate most port cleanings throughout the life of the tool. I like using it because of what I just mentioned and several years now of comparing both in my LB's, saws, trimmers, blowers and even snowmobiles. Don't like the price, but I think the extra technology in syn oil is worth it!

I do use marine grade oil in my outboard engine, and the "regular" stuff in my chain saw and string trimmer engines. I never gave a thought to the reason there are two different oils, but the temperature argument works for me. While they both have similar temperature at the ignition site, I have no doubt that the water cooled engine runs at a lower temperature and that could be enough to make a different oil formulation beneficial. I'm not saying it does, but I do take the input about engine temperature as a justification for using different oils. I've never accepted synthetic oils, that is the extra cost. The lessons on this thread cause me to rethink, at least for two cycle engines.

Try some synthetic oil in any of your 2 stroke engines. I think you'll be impressed enough to find the cost difference worth the extra to use the synthetic. One example. My ex-father law, and highly experienced boatsman, bought a new Yamaha 200 outboard for his boat which he at the time used not only for pleasure but also for Coast Guard patrols around Charlotte Harbor in Florida. He maintained his engines to factory recommedations from the dealer where he purchased it. After about 4 or 5 seasons of moderate use, and using Havoline TCW-III rated oil(price conscience), he experienced a total powerhead failure of which even a factory rep could not explain, but not sure they ruled out the oil as cause. They did give him $7000 credit for the purchase of a new engine to which I don't know if he ever then switched oil brands. Now, I'm not saying Havoline oil is not good. Heck, I've used the 4 cycle motor oils for years with good results. Using their 30w now in all my smaller 4's, but what I am saying is why take a chance with today's technology in lubricants in protecting new $300 dollar saws, trimmers or $14,000 outboards with running an oil that saves you $10-$15 bucks per gallon. Personally, I don't take the chance. New or used 2 cycles for me now get to bathe in synthetics.

I think you guys are way overthinking this oil thing. There is 2 stroke stuff around that is probably older that you guys that runs, and think what rubbish they put in them back then.

I just put in what the manual says, add a touch more oil, and call it good. I doubt your stuff will last any longer than mine.

I use snowmobile oil in everything (Castrol Go Snow! right now) because I have it and its good oil.
A couple years ago I figured I'd try some Amsoil 100:1 oil. I mixed up a gallon at 60:1 (because I was nervous of 100:1) and ran it in an old Ski-Doo. That sonofagun ran better than ever before. Idled better, tached up better, just plain felt better. I had to lean the carb to get it to run right but that jivved with what Amsoil said.
Then I ran out of that and put in some 50:1 with regular oil. That seemed to run okay too for the few miles to get home but the next night the engine burned down from inadequate lubrication.
I didn't richen the mixture again though so I've never really known if it were that or too lean a mix with regular oil. Anyway I quit using the 100:1 because I got an oil injected machine and didn't want to have two kinds of oil hanging around (you're not supposed to use 100:1 in an injection system).
I've still got a half quart of the 100:1, next time my chainsaw can is empty I believe I'll mix it up.

Not overthinking, over testing, maybe and that's your opinion. I gaurantee there are many 2 stroke engines around this world older than 37 years and still running fine. Were they all used every year or day for that matter on 30 weight motor oil mixed at 16:1? More than likely not, or you could haved scraped enough carbon out of the muffler, rings, head and ports to light up and barbecue enough chicken to feed 20 people! How much experience have you had with testing oils or different equipment mith? What type of oil do you use and why, is cost or availability a factor for you? I personally have owned LAWN BOY mowers and old antique saws several years older than me, and also have had hand me down tools from granparents that could have been still running if they had not been run on 30 w motor oil @ 16:1 scorn up with lost compression and excessive coking of the ports but then again, the manus directions were followed because that's all the technology had to offer 40 years ago.

Anyone wonder why there's a discussion on "oil mix ration" on the "Lawn and Garden Tractor" forum? How many people have 2-cycle engines in their Lawn or Garden Tractor?

I'd see this as a discussion that could take place on the lawn mower forum, there are a number of Lawn Boys about that are 2-cycle.

Carrying on, I had a Johnson 9.9 HP Outboard that was purchased new in about 1986 and the manual called for either 75:1 or 100:1, I don't recall. In any case on one trip to the shop due to some operational problems I was told to use a 50:1 ration, Johnson had withdrawn the old ration as not sufficient. That engine failed with major problems about 5 years ago, and it didn't have a lot of hours. I can only guess it as under 500. My replacement engine is run at 50:1.

For some reason my farm seems to grow chainsaws, they just appear out of nowhere. The problem is we just get 'em running good and they disappear again.
The proceedure is pretty simple though, first I pull the exhaust and burn the carbon out of it. You can tell who pays attention when they add oil, sometimes you'll have big old balls of carbon in there and they block up the exhaust and the saw won't run for beans. I usually burn the whole exhaust clean with a torch.

The other step is to drain the chain oil out of the gas.....

Curtludwig, we have all been there if you has been around chain saws for any period of time. I have seen many saws destroyed because of too little oil, never because of too much oil, except as you mention. And even that did not destroy the saw.

So, that's how to clean the exhaust: "burn the whole exhaust clean with a torch." What kind of a torch does it take, or how hot? Can one due it with propane or mapp gas?

My original post was about mix ratios for a Lawn Boy and a complete overhaul and the mix I was thinking of running afterwards, with what type of oil. Yes, one would think that these questions are better suited for the LAWN MOWER forum, but I was told that more LB owners and tinkerers hung out here and would be more apt to answer my questions. That's why I started to fog up this forum, no pund intended. I like to hear actual "facts" of who dunnit and why, with what happened scenarios, not just all "well it works for me" attitudes, but I'M ENJOYING ALL responses.

bill_in_nc, I suspect your excellent experience with marine 2-stroke oil is due more to your 20:1 mix than the idea that marine oil is just as good for air-cooled engines as the synthetic stuff sold by Husqvarna, Stihl, Echo, Mobil, Amzoil, etc. (although I've never seen any kind of a study to prove it.)

I absolutely agree with you that 50:1 nonsense is for the EPA and not the engine. I never go leaner than 32:1 with any oil in any equipment.

By the way, what will they do with chainsaws when they outlaw 2-stroke engines completely? Will someone finally start building a clean 2-stroke? (fuel-injection?) Will chainsaws get an exception? Will they have 4-stroke motors and weigh an extra 3 lbs. and send you home with a headache from the noise?

You know montesa, at this time, even with all the EPA restrictions and 2 cycle engines, I don't think smaller 2 strokes will ever be totally banned from new production. There is still too much of an advantage and power to weight ratio to warrant not to produce them in certain type of equipment. There are a few companies left ie Bombardier/Lear Jet, that have enough financial capabilities to stay ahead of the R&D in takes to keep the larger displacement engines running more efficiently and for the GREEN WIENERS, cleaner. I think if Toro/LawnBoy could have somehow redirected the intake/combustion, added fuel injection, manadated fully synthetic oil in their engines only, or added a catalytic convertor, they could have meet EPA regs. Did they want to spend the extra money to develop, would it make the every so light and easy to manuever mower more heavy and cumbersome? Probably some of the biggest reasons they chose not to. I'll buy and use 2 strokes as a first option as long as I can. If I ever have to resort to a 4cycle trimmer or chain saw, then I give up my power tools. They only engine I will want to drain a crankcase on will be larger mowers, cars, trucks, marine, etc. If this man can carry it, then in needs to be a 2 strokin' high revvin' long livin', 2 STROKE!!!

Four cycle trimmers are available now. I have run one. It is made by one of the major trimmer companies, and I don't remember which. It did not appear to be much heavier, only much more costly.

Sure, but who really wants to have to worry about changing oil with a thimble and eye dropper? Has to be a pain! I'd rather mix it once, and run with it.

One of my longest lasting trimmers has been my Ryobi 4 stroke. Oil change is as easy as mixing a gallon of 2 cycle oil. Nothing to it. As far as RPM is concerned it revs every bit as high as most 2 strokes.