What Does Oil- Fuel Ratio Really Mean?

[Gypo Logger]

Although, I generaly stick with 50:1 Stihl mix, I bought some Tanaka 2- stroke engine oil in a handy mix bottle. This 16 oz. bottle will mix 6 gallons of fuel. Therefore what would the ratio be?
My question is: If a 2- cycle mix is made more concentrated , wouldnt the ratio be lower? Would oils such as optimol be thicker in concentration, thus requiring more fuel to dilute it? Which in essence would make 100:1 the same as 50:1 in the final analisis?
Anyway, I havent tried the Tanaka mix yet, but I know their saws are at least as good as Shindaiwa from what I have heard.
The Tanaka mix appears to be made in Auburn Wash.
John

 

[Fish]

@48:1
I don't know how you could make the oil more concentrated,
as that is what it is, oil. I have a hard time going over 50:1 in any
two cycle, and think this race to astronomically high ratios are a
lot of hype, and I couldn't recommend it to anyone. A lot of
emotion and testimonies abound when a miracle oil believer
makes a case for their own pet oil{s}, which reminds me of the
hype about slick 50.
I am conservative an say stick with an oil put out by one of the
major brands, and that would be best.
Fish

 

[Gypo Logger]

Hi John, When I go into into a shop for the first time, I always buy something first before I start really talking about saws. This is a great way of breaking the ice and allows unrestricted pumping of imformation and sometimes gains access to their attic for old saws and possibly some 1/2 pitch chisel chain and some leads on woodlots. Sometimes I lurk around at my favourite dealer and sell saws for them when they are busy and sharpen their customers chain freehand on the counter after suggesting they buy a filing kit, which always leads to the inevitable question: "Got any standing timber you can sell me"?
So anyway, getting back to oil, after I bought the 2 cycle oil from the Tanaka dealer, he tried to sell me some Optimal and said it coated the pores in the cylinder and gave more compression, longevity etc. I didnt buy it, but I see what your saying about claims that are made about oil.
As far as concentrated oil is concerned, wouldnt two cycle mix be just diluted high grade grease? Like If I took high grade bearing grease that was good at very high temperatures and diluted it with fuel, wouldnt it do the trick in a saw?
I am not trying to suggest I would do this unless in a pinch, but rather trying to define what this oil thing is all about. What would the proper ratio of grease to fuel be to make it just right?
Do synthetic oils have more libricity and tackifiability, thereby adhering better to moving metal parts?
I am not really, really crazy, I am just giving some food for thought.
John

 

[Fish]

I firmly believe that Amsoil is just recycled Walmart grease.
They just don't want any problems by throwing it in the dumpster
so they are marketing this wonder mix. Tech 2000=Amsoil
I am not sure though.
Fish

 

[tony marks]

this ought to be fun,to watch.fish ,i dont know what its made of
but it didnt impress me much after using it about 3 wks.
like ive said before ,coulda been something i was doing wrong.
mabe. later now

 

[tundraotto]

howdy fellas, about synthetic oils and chainsaws:

the primary advantage of syntherics is their even particle size (the "liquid bearings" that make oil do what it does). through the process of making synthetic oil as opposed to blending and refining mineral oils enables the process to almost completely eliminate different size particles. all this results in extremely uniformly sized particles in oil. these particles being very uniform results for the oil to be much thinner while containing the same amount of the desired size particles. this is a huge advantage in engines as 90% of wear occurs before oil has reached the critical parts. synthetic, being much more fluid reaches the parts much quicker and therefore minimizes wear. also this results in much higher temperatures required for the oil to break down as the oil "ages" (ie. burns down) - ie. the different size particles burn down at a different rate, thus resulting in carbon buildup. the synthetic oil can have many more of the "correct" size particles to allow a sufficient amount of particles to remain after the oil starts to break down. this is very useful in a hot aircooled 2stroke application such as chainsaws. on a 4stroke i also wouldnt increase the oil change intervals - its just doing a better job while its in there - you can go longer than mineral oil but the oil breakdown still occurs.

i would never go leaner just because i used synthetic - just believe that they do their job better than the mineral oils and it does not really have very much price penalty in a chain saw - mobil mx2t costs $3.50 for enough to make about 10gallons from. on a car - i still do it too, but it hurts a little more since the quantities involved - ie 7 quarts for my truck. these opinions are strictly my own and they might be complete bullcrap but this is my understanding of the matter after being interested in this subject for over 10 years. a good example for me was my fathers diesel mercedes 250D from 1986 that had synthetic oil used in it exclusively for over 140k miles - the cams were pulled for service by our dealer and they were still completely within factory specs for new cams. now whether this was just because the motor was built well or because of the good oil i dont know - but i'll take the insurance of synthetics on every single thing i run that uses oil. i may be pretty far gone though

 

[John in MA]

Yamaha spec'd 100:1 for their outboards a few years ago. Funny thing happened--people started complaining about brand new motors seizing. So, Yammie went to 75:1 and the problem rate has dropped.

I still run everything I have at original, or at least reasonable, fuel ratios, although I use the number for the manufactur's own oils. I figure the quality has gone up enough in the past 30 years to use 3rd party oil. Homelite said 16:1 for their own oil in a C-7, but 10:1 for other oils. No way I'm doing that if I can avoid it. My Seagull outboard runs at 10:1--good for keeping the bugs away.

 

[Harley]

Oil

Hello,

 

[Harley]

Oil

I'll just continue on after that.

The viscosity (thickness) of an oil, grease, or other petroleum product is based on the length of the hydrocarbon chains that form the individual molecules. In other words gas is shorter that 20w is shorter than 90w gear oil.

The comparison is like stirring spagehti versus stiring baked beans or something shorter. The longer chains creater greater friction, thus increasing viscosity.

I don't think that if you mixed bearing grease with gas, it would be useful, as the lubricating chains would not be small enough to get to where they do the most good.

The temperature at which these chains break down is subjective. What I mean by that is a long chain can break rather easily compared with a short one or vice versa. Its dependant on what atoms makeup the chains other than hydrogen and carbon. Its also dependant on the shape the chains make. A round chain ( no open ends) takes more energy to break than an open ended one.

The benefit to synthetics is that you can better select what molecules you are making. Example; I can chose to make an oil with all chain molecules, thus making it a higher temp oil. Of course you can make balls or rollers, or whatever you can think up. Natural oils are just grouped by what temperature they distill off at. They maybe of any shape so long as they came off at the same temp.

I once read that you shouldn't breakin an engine(4 Cycle) on snythetic oils They never gave a good reason though. It was just based on the experience of about twenty years ago. I imagine things have changed since then.

I hope this helps.

 

[jokers]

The logic still holds true about engine break in on synthetic oil. With a four cycle, you are alledged to not get proper wear in so you have increased oil consumption and never attain peak potential horespower. On a two cycle, oil consumption stays the same of course, but you don`t get peak performance because you don`t get the proper wear in. I say alledged, but a significant amount of study and analysis has gone into this topic, and the conclusion remains that break in wear is unsatisfactory. Russ

 

[Walt Galer]

Howdy,

I agree about the length of the constituant hydrocarbon molecular chain. I also agree about the hesitation about synthetics. Personally, I would never use them in a two cycle, especially a used machine.

I believe you will find, surprisingly, that most better mix oils for chainsaws are formulated from a base stock that is actually from reprocessed motoroil! This assures the shorter hydrocarbon and is like a second and third refining step. Recycled is not always a bad thing.

Way back when, the 16:1 ratio's existed because of the heavier oil used and the loosness of the old motors. With more consistant and shorter hydrocarbons, it became possible to get to the 40:1 and 50:1 that the major manufacturer's use today. For those old Homelite saws, I would recommend the modern oil, but at 32:1. There is no need to breath more unburned oil and smoke than that.

Attempts to use the 100:1 mix products in old machines is usually a disaster. They just clean up the engine wear surfaces making a loose as a goose engine even looser. The result is often a very unpretty crash. They breifly run better than they ever did, and the debris shows no evidence of lubrication failure.

Regards,
Walt Galer

 

[Todd]

Years ago I heard from a motorcycle racer that lower ratios(more oil) = more heat produced and higher ratios produce more power. This makes sense to me because oils burn hotter than gasoline and at high rpms engines need a fuel that burns quickly. On the other hand higher ratios could cause reduced lubrication, more friction, heat and engine failure. So from this it could be possible too much oil is bad and not enough is bad also. I'm guessing the manufacturers have spent plenty $$$ figuring out what is the best ratio, oil etc. Question is, with the multi-million in marketing schemes which products are hype and which are real?

 

[Harley]

Hello,

The thing about recycled oil is that I hate to pay for stuff that I gave away for free.

Something I've noticed here is that people tend to link a flames temperature with its speed. This is not really the truth. Although an oxy-actelene flame burns hot and fast, not all flames follow that pattern. Again it has to do with the shape and the length of the hydrocarbon.

Alchohol burns cool, but has a realativly fast flame speed. Hydrogen burns like poo through a goose. The flame speed is dependant on chain reactions, that break down the molecule into smaller and samller sizes. When they get to a certain size they break apart and recombine into the products of combustion( Water, CO2). The reason why hydrogen burns so fast is that the chain reaction of combustion is only a couple of reactions long.

Air to fuel ratio also affects how fast the flame speed travels. A slightly rich mixture burns the fastest. This is because free radicals are developed. A free radical is basically a free atom floating around in the reaction that hasn't combined to form a product of combustion yet. These free radicals attack the hydrocarbon chains much faster making the chain reactions branch, and become shorter. Kindof making a bypass to the finial product. Its almost like a pool table at the break, alot of motion and a lot of things happening.

As far as mix ratio is concerned, I don't think that you could predict one ratio is better than another just by sitting here and looking at it. The key is to do experimentation on a dyno, and see what ratio gives the most power and by how much.

Of course my question is now how much power is there to be gained by changing my mix ratio from 50:1 to 32:1?

My guess is less than a third of a percent. I might be wrong, I never did the experiment. Is that power worth using more oil? Is longevity increased? How Much?

These are the questions the saw manufacturers spend developement dollars on.


Harley

 

[UrbanEarth]

I don't know why an old saw wouldn't benefit from a better oil. I am using Optimol (100:1) in my 20 year old Husky 162 with no problems whatsoever. I have also been using it for about 5 years.

Alan

 

[tundraotto]

uh-oh - your scaring me urbanearth!!! i completely agree with you that older saws would absolutely benefit from better oils, but why thin the ratios?????!!!! you are getting better lubrication - why use less to bring you back to square one? why not use the same ratio as with conventional oils and enjoy the benefits of better lubrication - isnt that what were after with synthetics?

 

[JimL]

I buy my 2cycle oil in a 5 galon bucket from stihl. I have always had good luck with it so I see no need to change. I talked to a stihl rep a couple weeks ago and he mentioned that stihl was thinking about adding some sort of additive that will do like John said, fill the pores in the piston and cylinder.
Hope I can find more out when I go to the product update class that stihl puts out in february.

 

[wendell hollis]

Hello All,
This is a very good topic here, Good info.
Talking about longevity I swiched my Jonsey 2065 down to a 40 to 1 from the recomended 50 to 1. I was hoping to get a little more lubracation to it since it getting high in hours and runs hard every day. I was cutting a 20" dead lodgepole about 60' worth today and the saw just pulls down so far and cuts like a bat out of hades It seems to have a little better pull in the long and heavy cuts. I do not give it any breathing time between cuts, out of one and in the next. It has made an improvement even if it is subtle. I use the Husky white bottle mix.

Hark!! I hear more logtrucks comming!!
Must Saw !!!

P.S. Gypo, Trucks # 16 & 17 since Oct. 1st are comming in later this week. Non fiber challenged here. Also I haven't had time to get my pics on yet. See Ya,

Wendell

 

[UrbanEarth]

Tundraotto, why change the ratio that is from the manufacturer? I would assume that they have done the testing and recommend that ratio for a reason. If everyone switched to the new oil and rate and motors started getting torched, they wouldn't have much repeat business would they? And in this day of lawsuits, I can't see a manufacturer not covering their butts and doing the research.

Alan

 

[tundraotto]

thats what im saying urbanearth!!!! you are the one thinning the ratios!!!! youre running 100:1 like you said with optimol?! husky recommends 40:1 or 50:1 on semi recent (ie last 10 years) models.

i do think that the manufacturers lean them out for epa emissions though - how much i dont know. this is why i go with the synthetic and keep at 40:1 - for extra insurance. 20% richer is much better than 100% leaner i guarantee you.

 

[UrbanEarth]

Sorry, Tundraotto, I should have been more specific. The Oil Manufacturer, Optimol, says to use a ratio of 100:1, not Husky. Optimol would be responsible if engines started burning up using their ratios. I know that with their 4 stroke oil, they double the engine warranty for all motors, if you fill and use only Opti4. I can't remember if they do the same with 2 stroke.

Alan