1:40 oil and gasoline mix

[alsayyed]

 I have mixed 1:40 i.e. one liter of Stihl 2 stroke oil with 40 liters of gasoline and it is working very good no piston fried. The only problem I have encountered that smoke when it starts and when it runs. Second things I have discovered that I have to do 3 spin to start the chain saw. I thought about an idea how about I go for 1:45 i.e. one liter of Stihl 2 stroke oil with 45 liter of gasoline.
Do you think it is good idea for experimenting purpose? Maybe I can reduce the amount of smoke.

[rebocardo]

How quickly do you go through 40 liters of gasoline/petrol? 

With that large amount I would worry about it properly mixing and it staying that way.

FWIW: I run all my oil (Stihl/Husky/ etc.) at 40:1 too.

[SawTroll]

Don't let the mix get too old (maximum a month; I believe), and shake it before each tank filling.

1 to 50 should be sufficient oil if it is a proper mix of premium gas and proper synthetic mix oil, and it would probably create less smoke.

1 to fourty leaves a better margin of error though, and some like 1 to 32 on large saws, so take your pick.....

[fishhuntcutwood]

My first thought was, "Wow, that's alot of mix..."  But maybe you use that much in a month.  If not, you're shooting yourself in the foot by letting that much sit that long.

But, I run 40:1 as well.  Did you run 50:1 at one point in time?  If so, you'll need to readjust your carb a bit.  Properly mixed fuel with a properly adjusted carb shouldn't smoke.  You can tune that out.

That said, I seem to remember you buying a 650 and milling with it...  If you're milling, I'd rather run it rich, and at a lower RPM as a fact anyway.  If this is your 650 on a milling set up, I might just leave it as it is, depending on where it's revving.

[Ianab]

I think from memory you were running 50:1, and your saw siezed, twice. :(

Now you are running 40:1 and it smokes a little, but hasn't siezed... I think I'd just ignore the smoke and carry on at 40:1 ;)

Cheers

Ian

[alsayyed]

yes I thank you all for your opinion I should leave it 1:40 or 1:50 but I will add more oil like 100 ml more try and see. or I just leave it at 1:40.

[fishhuntcutwood]

Before you add more oil, lets deal with the amount you're mixing.  Do you use 40 litres of mix in a month?  If not, don't do it.  I mix my fuel two gallons at a time.  That hardly ever lasts me a month, but if it does, I can dump it and move on.  Bad gas will seize a saw, no matter what ratio it's at.

You should be alright milliing at 40:1 if it's properly mixed and not too old.  But more importantly, make sure your saw is properly tuned.  You can seize a saw running fuel at 32:1 if your saw isn't adjusted correctly.  40:1 is fine for milling, but make sure your saw is running properly.  Keep the saw  below max rpm, and don't try to rush through your cuts, either by pushing, or by running your saw too fast.  I wouldn't worry about adding more oil yet.  But if you do, TUNE YOUR SAW.   You can mess up a saw running it too rich as well.

[SawTroll]

Before you add more oil, lets deal with the amount you're mixing.  Do you use 40 litres of mix in a month?  If not, don't do it.  I mix my fuel two gallons at a time.  That hardly ever lasts me a month, but if it does, I can dump it and move on.  Bad gas will seize a saw, no matter what ratio it's at. ...

You are right, as usual........

[MDP]

I've been told by a couple of good saw mechanics that too much oil can be just as bad as too little, they say that oil burns hotter than gas or maybe the engine gets hotter in order to burn the extra oil that is mixed in the gas.  I don't recall exactly which one it was but they were real clear on the point. The factrory says 50:1 with a quality oil, I'ld go with that.



Mark

[alsayyed]

I am sorry I should make this clearer to everyone. I normally mix the followings quantity. This recipe for 40:1 or 1:40 mix which way you read it.

20 liters of premier gasoline with 375 ml of Stihl 2 stroke oil.
Or 5.28 gallons with 12.68 fluid ounces of Stihl 2 stroke oil.
And I keep this for almost 10 to 15 days because the Stihl machines like the MS 650 and MS 660 consume too much gas during operation.
I hope this is clear. What I am saying my next step is to reduce the amount of 2 stroke oil. It should be as follows
20 liters of premier gasoline with 350 ml of Stihl 2 stroke oil.

[fishhuntcutwood]

OK, if you're going through fuel that quickly, you're probably OK.

So from what you're telling us, run your 40:1, tune your saw to below max rpm for milling, and if it smokes a bit, let it. 

I'm not sure if I am following you.  In one post, you talk about adding 100ml of oil, and now you're talking about reducing the oil.  No need to reduce your oil.  Why are you wanting to do that?  Is it true you've seized two saws?

Run it at 40:1, properly tuned, and leave it be.  Shouldn't seize like that.

[fishhuntcutwood]

You are right, as usual........

Ha!  Thanks.  No more than you though...

[oldsaw]

I am sorry I should make this clearer to everyone. I normally mix the followings quantity. This recipe for 40:1 or 1:40 mix which way you read it.

20 liters of premier gasoline with 375 ml of Stihl 2 stroke oil.
Or 5.28 gallons with 12.68 fluid ounces of Stihl 2 stroke oil.
And I keep this for almost 10 to 15 days because the Stihl machines like the MS 650 and MS 660 consume too much gas during operation.
I hope this is clear. What I am saying my next step is to reduce the amount of 2 stroke oil. It should be as follows
20 liters of premier gasoline with 350 ml of Stihl 2 stroke oil.

Okay, now I am jealous.  That is some serious cutting, I never get time for that.  If I burn a gallon or two in a month, I'm feeling pretty good about myself.

Mark

[weimedog]

Just a couple of comments...

I found over the years mixing gas for two strokes with the non-synthetics is a catch twenty two. Too much oil and they gum up the exaust, to little and they don't offer as much lubricity...engine life suffered over a season of racing.

The one of the advantages of the better synthetics & semi synthetics  is that they will burn clean with a heavier mixture. The Echo power blend & Mobil One both work well in my experience with mixtures in the 32:1 range. I have tried "brand" name oils that won't burn clean at those mixtures. Last year my local Auto Zone had a spell where they wouldn't stock Mobil One Racing Two Stroke Oil (MX-2T) so I searched for an alternative. (I use a lot of oil) But ended up going back to a oil from my past...so to reveiw a bit of history.

There is a good brand sold for motorcycles ...Belray. The "MC1" has been around for a very long time. Belray, Klotz and Golden Spectro were long time preferences in the motorcycle racing world; all made really "high" end two stroke oils. Belray & Klotz both were early to offer full synthetics years ago. The first Belray offering was a synthetic but I was never able to get a clean burn with a heavier mixture than 40:1....then they released the "H1R" version and it WOULD in fact burn clean at 32:1...nice clean pipe and exhaust port after a year or two of use... The BEST to that point in time.

Then I ran across the Mobil One MX-2T and it works as well as the H1R ...just costs a lot less. I later learned it was equal if not better than the H1R but the "economy" of scale Mobil has to work with allowed a lower price...Now everything I have two stroke is using 32:1 Mobil One MX2T. Really pleased to this point.

One of the things motorcycle racing hammered home was smaller bore (125's) usually means more RPM's....and they LIKE to live with more oil. (IF it burns CLEAN!!) The 32:1 mixes work well with them. Better life and a cooler running motor was what I saw with mine.  The old BIG bore two stroke (500cc class) liked a little less oil...38:1 & 40:1 worked well with them. 

The Belray H1R was the FIRST two stroke oil I had used that I could mix at 32:1 and still run my older big bore two strokes on without all that tar in the exhaust...Mobil One was the Second, and I found last year that if I couldn't find Mobil One MX 2T, Echo Power Blend seems to work as well. So I quit using Belray simply because I found two much lower cost oils that to this point in time seem to burn as clean and lubricate as well.

To give you an idea of how long I have been at the motorcycle game....a PATIAL list of TWO strokes I have raced and owned over the years.

Bultaco's including Sherpa S 125, 200 and Pursang 250's from 1970 until around 1974.
Maico 400's and 440 from 1974 until 1978
KTM's 420's & 250's from 1978 until 1982
Kawasaki 125 and 250's from 1982-1983
Honda's of all sizes and shapes from 1984 until 1996, then things get weird.
Fourstrokes...and then retro back to old stuff. My KIDS had 80's and 125's during those years. NOW I have:
1979 KTM420's, 1982 Husqvarna 430, and a pair of VOR's (503 & 450)

Burned a LOT of two stroke oil over the years. Build a lot of motors.

[SawTroll]

...And I keep this for almost 10 to 15 days because the Stihl machines like the MS 650 and MS 660 consume too much gas during operation.
....

That's cool then!

And your saw, that started out as a 650, is now effectively a 660, isn't it..... 8)