Facts reguarding gas to oil ratios????

[martyinmi]

Just when I think that I THINK I know what the proper ratio should be, I read something else that tells me how wrong I am. I think?
I was visiting another forum last evening where a few guys strongly promoted 100:1 ratios. I clicked their links and read what the "experts" wrote.....and I have to say that it made sense. They claimed that running too much oil can actually lead to a too lean condition and that the excess oil causes detonation, which produces too much heat and will SEIZE THINGS UP. It really made sense to me. For a while, anyways.
I visited another site and read "expert" more opinions.....this time stating that any mixture with less than 1 part oil per 60 parts gasoline (60:1) will positively lead to premature engine failure. They gave all their reasons...and they also made sense. They said that a piston in a professionally built engine will grow enough to cause roughly .0005' to .001" interference (piston is actually bigger than the bore) while running flat out, and that the little extra lube is positively necessary, and without it things will SEIZE UP.
I've been running between 40 and 50 to 1 for as long as I can remember, depending on what oil I'm using, what mood I'm in, etc. Both camps tell me I'm wrong for not running a consistent ratio every time, in that if I'm running 40:1 and jump to 50:1, the engine will need to be re-tuned for guaranteed maximum longevity.

Both sides kinda-sorta make sense and they both illustrate the validity of their points of view very well. It's got me scratching my balding head now. ???

Whada ya all think? I already know what dear 'ol uncle Al thinks, but I'm hoping he'll still contribute.

   

[thecfarm]

I saw the title and thought Al will like this one. ;D  Going to your Uncle's for Thanksgiving? That way you guys can talk about while eating.  :D  As he says,I will stick to my 32:1.

[martyinmi]

I saw the title and thought Al will like this one. ;D  Going to your Uncle's for Thanksgiving? That way you guys can talk about while eating.  :D  As he says,I will stick to my 32:1.

Some day, before one of us ends up meeting their maker, I'd like to hook up with 'ol Al.
There's just something about his internet personality that makes me want to arm-wrestle him for a beer! :D
I've sent the 'ol fart pm's two years in a row, trying to get him to come up for the pig roast.
He just keeps on making up flimsy excuses!
Oh well, maybe next summer!

[JohnG28]

 :D :D :D

[7sleeper]

2 stroke oil is ok for me.

7

[mad murdock]

I will stick with my run of the mill 2 cycle oil and 32:1 ratio as well. The synthetics do lube better so you can run a leaner mix say 50:1, and it is fine. Amsoil 2 cycle can be run 100:1, I don't think I would go that lean with anything else. As far as loading up the engine, or making the file
Mix too lean? I don't really buy those arguments, the ultimate check is to pull the spark plug and look at the color to see how it is running. If it is too much oil, it will foul the plug. Easy to monitor.

[SPIKER]

From what I can remember reading at OIL MFG sites, that is the people making 2cyc oils. it all depends on the OIL MFG as to what ix you should run firstly and then the Equipment MFG specs secondary.   

Here was the reasoning behind what they claim, one the 2cycle oil manufacture is making an oil that is designed to be mixed at a ratio (32:1 or 40:1 or 50:1.)

Note I have never seen an oil specify much different so using those specs.   Now some equipment will say run the engine with a fuel mix of 32:1 so therefore you should buy and run the mix for that engine using the mix specifying 32:1.    Now mind you these oil manufactures have done extensive tests on their materials and in most cases will make several mix ratios available.   

They have chemical makeups that are designed to mix, run and lubricate a standard generic 2 cycle engine.    The different companies making different mix ratios some companies make several ratios mixes to match and match with different engine manufactures.   The also state that if you buy 50:1 MIX and use it with that 50:1 it should run and lubricate ANY small engine well enough for it to run and live a normal life.   

So what you end up with is oil companies stating their MIX is good for any engine.   

THEN Engine Manufactures that say only mix with THEIR specific brand of OIL or OIL MIX RATIO.   

SO I hope I have added to your confusion :D ok just kidding ;)

I generally run with the same mix ratio in all my 2 cycle engines even though the 4 different brands of machines are all over the place from 32:1 to 50:1.   I have Homelite, Poulan, Poluan Pro, WeedEater and china no name machines all running 32:1 Poulan oil at the moment all work fine without fouling or lean conditions per plug inspections over the last 15 years...

Mark

[Yatt]

I run high grade synthetic at 40:1 with a stabilizer.

FWIW this summer I made friends with the loggers that were cutting a 67 acre parcel near my house.  The temp was in the mid 90's for a couple weeks and they worked as they did every day.  About 3 semis a day came out of the site.  They were running Stihl 660's with a mix 1 quart of non detergent 30# motor oil in 5 gallons of gas.  So a ratio of 20:1.  Those boys worked the saws hard day in and day out.  No smoke once they were hot and they said the new saws were used for 1 year in the woods felling then another year on the landing before they traded.  They had no issues whatsoever.  I did a few mental guesses and figure they put a conservative 1500 hours on those saws before trading.  So don't knock success.

[MidWestTree]

I've run a 40:1 mix in my saws for decades and they work hard for a living. I've never had a bearing, piston or ring failure issue from to little oil and I have been into every saw I've bought at some point over the years when they were flat worn out and tired from LOTS of hours of hard use.

No excessive carbon buildups on the piston dome's or ring grooves and everything's nice and shiny when taken apart for servicing. The only exception being a few saws that developed air leaks and scored the exhaust side, some of the guys running them just don't have a clue of symptoms of lean running or air leaks, can't put that on the oil or mix ratio.

I think 50:1 is really pushing it for any air cooled OPE engine and the only benefit from that is less emissions. In water cooled boat engines etc. not nearly as big a deal with so much less heat being present.

[AdkStihl]

I'm not gonna argue which ratio is best, but I want to point something out.
A carb that is tuned properly for a 50:1 ratio will run lean when switched to 40:1 or 32:1.
And a carb that is properly tuned for 32:1 will run pig rich if switched to 50:1.

I burn VP SEF @ 40:1 & 32:1 depending on the saw.

I've seen the insides of too many saws that have lived their lives on 50:1 and I will tell you that there is not enough oil getting to the bottom end at this ratio. The big end bearing and crank bearings had no residual oil in them, hence the reason why they were being torn apart!!

[Al_Smith]

Well my adpoted nephew Marty in Mich just can't help himslf trying to crank up his dear old unc .I kind of expect it anymore else it wouldn't be Marty which I doubt seriously I could beat at arm wrestling --but there was a day when old uncle Al had arms like a gorrilla .

Oil,much ado ,fuss .cuss carry on .Ammies eral,purple pumpkin patch 10 thousand others .Geeze !

So they say more oil makes it run leaner .So using that idea less is better ? Might as well run straight gas then ,eh?

[Al_Smith]

--so more again ,as usual .

The last guy I said that straight gas thing to got in a huff and hasn't said boo since .

Gasoline ! Lawdy we have regular gas which contains moonshine .Aviation gas ,racing gas ,pure gas from lake Erie .

It's a chainsaw not a vintage Ford 429 Cobra fer Petes' sake .--more again--

[thecfarm]

I can hardly wait.  ;D

[Al_Smith]

So we have these old saws much older than Marty .They ran the things on regular gas with 30 WT motor oil ,they still run .Slow but they still get-er-done .

Trot on out to the dead pile of a Stihl dealer and count the pile of 029's stacked up like cord wood some time then tell me all about 50 to 1 mix .This is progress ?See Marty isn't the only one who can stir the fire --great sport . ;D

[HiTech]

I use a 50:1 oil. When mixing a 2.5 gallon can I ad 2.3 gallons of gas to one jug of oil. When I mix a 5 gallon can I ad 4.6 gallons of gas to two jugs of oil. My little jugs of oil are for 2.5 gallon mix. My saws are Husqvarna so I use Husqvarna XP oil. Actually it is a little richer oil to gas ratio than suggested but it works well for me. 

[AdkStihl]

Trot on out to the dead pile of a Stihl dealer and count the pile of 029's stacked up like cord wood some time then tell me all about 50 to 1 mix .

EXACTLY Uncle Al......Exactly!!

And in that pile I'm sure you'll more than a pile of toasted clamshell turds.  smiley_antlers

[AdkStihl]

I use a 50:1 oil.....it works well for me.

I see your location is Northern NY. Whereabouts if you don't mind me asking?

[kenskip1]

From the replies I will add that I use Amsoil at 40/1. I would be more worried about gasoline with ethanol in it than 40/50-1 mixtures.I have been using this oil for the past 8 years and have never had an issue with it, Ken

[HiTech]

I use a 50:1 oil.....it works well for me.

Carthage, New York



I see your location is Northern NY. Whereabouts if you don't mind me asking?

[thecfarm]

What about using high grade for gas?  :D

[AdkStihl]

From the replies I will add that I use Amsoil at 40/1. I would be more worried about gasoline with ethanol in it than 40/50-1 mixtures.I have been using this oil for the past 8 years and have never had an issue with it, Ken

I ran Amsoil @ 40:1 this summer. To me it seemed that Amsoil Saber is super concentrated like frozen orange juice!!
It was almost as if I had mixed brand "X" at 16:1.
It was too much smoke for me.
Perhaps I had mixed it 50:1 it would have been alright?
One other contributing factor was that it was mixed with 100LL which tends to burn rich anyway.

I like muh Motul

[AdkStihl]

]Carthage, New York

My wife just drove through there last night on her way home from Niagara Falls.
I have family in the Potsdam, Massena and Malone area.

[chucker]

  I am still using my 1987 jonsered 670 champ with all the original motor parts! cutting around 50 cords of hardwoods with it yearly and mixed at 32ozs. of quaker state 2 cycle oil to 5.5 gallons of gas. that's a mix of 22:1, SO MUCH FOR THE TO MUCH OIL  ISSUE! a fouled plug once in awhile I can live with! once again which is the cooling factor? the oil or the gas? gas is cold year round and oil is slippery all year round! your choice, your machine and your money!

[7sleeper]

I'm not gonna argue which ratio is best, but I want to point something out.
A carb that is tuned properly for a 50:1 ratio will run lean when switched to 40:1 or 32:1.
And a carb that is properly tuned for 32:1 will run pig rich if switched to 50:1.

I burn VP SEF @ 40:1 & 32:1 depending on the saw.

I've seen the insides of too many saws that have lived their lives on 50:1 and I will tell you that there is not enough oil getting to the bottom end at this ratio. The big end bearing and crank bearings had no residual oil in them, hence the reason why they were being torn apart!!

But the effects are minimal if detectable at all when switching from 50:1 to 40:1. I doubt that with a modern full synthetic oil you would ever notice a difference. What hasn't been said sofar is what I believe more important than any brand discussion.

What I see as the most important qualification of a good oil is:
1. fullsynthetic oil for aircooled engines
2. fullfills the following norms  API TC, JASO FC/FD, ISO L-EGD
These norms dictate if an oil is made for extreme high performance engines, low smoke, etc.!!! They are at the moment the strictest and highest norms. The very popular Stihl HP Ultra like many others do not fullfill the above norms. Many generic brands do. So I would be cautious what is written on the bottle before I make any mix.
For me I use a generic brand from a motorcycle accessory store that fullfills the above norms and I run at 40:1.

7

[Andyshine77]

The oil ratio topic never seems to end. I've been in many small two cycle engines, ran on many different oil ratios. Engines ran with more oil have less wear and run longer end of story. You need oil for more than simply lubrication. The seals need to stay wet with oil to seal properly, helps ring seal, and also acts as a cushion.   

Top end from an MS441 ran on Amsoil Saber @ 100:1 in the pics below. He stopped running her just in time, and yes it was tuned properly. 100:1 is not enough oil for small high rpm engines.http://www.maximausa.com/lube-news/summer01.php