mixing ratios for 2 stroke chainsaws

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Bare steal is still used to make things like frames, A-arms, etc.
Bare steal hasn't been used to make body panels for many decades.
I worked in the auto industry right out of college and then latter worked for Cleveland Cliffs Iron in their mining divsion. CCI now supplies most of the steel for the US auto industry.
Don’t think we’re making frames here for anything pretty much the only company rolling full cars of the production line here is Chryslers and all they make is minivans.
 
Don’t think we’re making frames here for anything pretty much the only company rolling full cars of the production line here is Chryslers and all they make is minivans.
All the suspension pieces, engine cradles are probaly still bare steel. I can assure you the body panels are all coated specialty steels. The steel supplier for that plant is probably the former AK steal just accross the river on the US side. Cleveland cliffs purchased that company primarily to get their Coates steel business.
Also keepnin mind that these coatings are such that visually they don't look much different than bare steel.
 
All the suspension pieces, engine cradles are probaly still bare steel. I can assure you the body panels are all coated specialty steels. The steel supplier for that plant is probably the former AK steal just accross the river on the US side. Cleveland cliffs purchased that company primarily to get their Coates steel business.
Also keepnin mind that these coatings are such that visually they don't look much different than bare steel.
Steel comes from the Toronto area a lot of it actually crosses the border as well going to the us.
 
Steel comes from the Toronto area a lot of it actually crosses the border as well going to the us.
I realise Canada has a steel industry in Sault Saint Marie, Hamilton and Toronto area, etc but it's small compared to the US and the US companies have patents on most of the new high strength and coated steels.
AK was Chryslers supplier of the year a few years ago and pretty much supplies nearly all of Chryslers steel.
Regardless supplier, bare steel is not used in body panels and hasn't been for 30 or more years.
 
FOR ABOUT THE FIFTH TIME... when fresh charge enters a two cycle the gasoline part flashes from fine liquid droplets form to vapor. When this happens the oil portion of the charge is deposited on the internal surfaces of the engine. So, anything that makes a two cycle engine burn less fuel also robs it of lubrication.
For about the fifth time, it is not burning less fuel. Less unused fuel is being puked out the exhaust.
You have no idea how much of the oil mixed with that waste got on the surface of anything.

Somewhere between 0% and 100% I suspect.
 
For about the fifth time, it is not burning less fuel. Less unused fuel is being puked out the exhaust.
You have no idea how much of the oil mixed with that waste got on the surface of anything.

Somewhere between 0% and 100% I suspect.
Wether it burns it or not doesn't matter. Less fuel and thus less oil is passing through the motor. This isn't a hard concept to understand.
And almost all of that oil gets deposited on the surface once the engine is up to temp. If you have liquid fuel passing into the combustion chamber the motor runs like **** due to it being lean. Just like a cold motor... and A/F ratio is a ratio of air to vaporized fuel, not liquid fuel...
Now think about it before you reply. This is basic two cycle operation we are talking about..
 
Yeah I know I was directing it at the never stray from 50:1 crowd. Down here Stihl manuals always used to say if not using stihl oil run 25:1 in pro saws. This was still in the manuals up to the last of the ms660 and ms880 can't remember what the ms661 manual says I'll see if I can find one.
The last 260 I bought used such verbiage. Which is a laugh, because Stihls oil has been low quality since forever.
 
Wether it burns it or not doesn't matter. Less fuel and thus less oil is passing through the motor. This isn't a hard concept to understand.
And almost all of that oil gets deposited on the surface once the engine is up to temp. If you have liquid fuel passing into the combustion chamber the motor runs like **** due to it being lean. Just like a cold motor... and A/F ratio is a ratio of air to vaporized fuel, not liquid fuel...
Now think about it before you reply. This is basic two cycle operation we are talking about..


I'm sure you have some alter and maybe candles to burn when you bow down to this.

But, in the meantime equipment coming in for oil related failures or using Stihl oil or whatever you are preaching just doesn't exist. Unless they forget to put any in.
 
I'm sure you have some alter and maybe candles to burn when you bow down to this.

But, in the meantime equipment coming in for oil related failures or using Stihl oil or whatever you are preaching just doesn't exist. Unless they forget to put any in.
Nice subject change...
Given you can't wrap your mind around basic two cycle operation I am betting your failure analysis isn't too hot either. Plus you are dealing with mostly homeowner junk that has low hours on it, correct.
 
Strato saws definitely seem to run hotter on the exhaust side, for that reason alone I would run 40:1 with a premium oil on the type. I had to replace a Husqvarna 570's piston and cylinder that was badly scored on the exhaust side, the owner was pretty negligent about sharpening his chains and overworked the saw. A premium oil at a richer oil mix ratio might have saved it, or at least minimized the damage.
They may be great for emissions and fuel efficiency, but they're more critical when it comes to overheating. The part of the charge that goes out with the exhaust helps cool things down on non-strato saws.
Heat is the killer, keep this in mind when you're choosing mixed ratios for any application. Some lighty loaded stuff can get away with a lot less, the old golf cart motors ran 128:1, but if you're doing something like milling with a saw, make sure your oil and mix ratio is appropriate.
 
Strato saws definitely seem to run hotter on the exhaust side, for that reason alone I would run 40:1 with a premium oil on the type. I had to replace a Husqvarna 570's piston and cylinder that was badly scored on the exhaust side, the owner was pretty negligent about sharpening his chains and overworked the saw. A premium oil at a richer oil mix ratio might have saved it, or at least minimized the damage.
They may be great for emissions and fuel efficiency, but they're more critical when it comes to overheating. The part of the charge that goes out with the exhaust helps cool things down on non-strato saws.
Heat is the killer, keep this in mind when you're choosing mixed ratios for any application. Some lighty loaded stuff can get away with a lot less, the old golf cart motors ran 128:1, but if you're doing something like milling with a saw, make sure your oil and mix ratio is appropriate.
Scoring like that is typically caused by two things. A air leak of some sort or drastically lean carb settings. No oil at any amount will stop a burn down if either factor gets bad enough.
as you stated strato saws do run hot, which is why IMO its a good idea to have Autotune or Mtronic in place. I know both these systems are bagged on by the Luddite crew but they really save alot of saws from premature failure and ensure good running all the time. The average saw user can't tune a saw to save his life. You can lump most saw mechanics in with saw users as well.
 
I realise Canada has a steel industry in Sault Saint Marie, Hamilton and Toronto area, etc but it's small compared to the US and the US companies have patents on most of the new high strength and coated steels.
AK was Chryslers supplier of the year a few years ago and pretty much supplies nearly all of Chryslers steel.
Regardless supplier, bare steel is not used in body panels and hasn't been for 30 or more years.
Body metal now a days sucks anyway it so thin(22ga and thinner) on most panels you can’t even weld it like you could on older cars it will warp to sh**.
 
I have only vintage Stihl saws. 031, 041, and 075's. All said, 'do not use high octane fuel'. Now, fifty years later, is what we know at the pump as 'high octane', similar in any way to the old gasoline? We all know the issues with ethanol, so I only run 'high octane' now. Am I helping my saws or are they slowly committing suicide by fuel? Oil, I mix 32:1 with high test gas and keep it two months, then it goes in the Ford.... I drain the saws, then start them, warm, to eliminate fuel in the system. Good or bad?
God bless
 
The best fuel you can run in your saws is ethanol-free. The octane rating doesn't mean squat until you reach a compression high enough that detonation becomes an issue.
 
Scoring like that is typically caused by two things. A air leak of some sort or drastically lean carb settings. No oil at any amount will stop a burn down if either factor gets bad enough.
as you stated strato saws do run hot, which is why IMO its a good idea to have Autotune or Mtronic in place. I know both these systems are bagged on by the Luddite crew but they really save alot of saws from premature failure and ensure good running all the time. The average saw user can't tune a saw to save his life. You can lump most saw mechanics in with saw users as well.
Yes, I think that a lean mixture may have contributed, who knows what the factory tune was. I'm betting the mixtures were never touched, the saw screamed neglect. I'm pretty sure though that this horrible chain contributed greatly to the overheating. I had to grind about a third of it off before it was usable again.
These cringe worthy saws both came from that owner, the cylinder on the 570 look to have had very little time, and the crank seals were good. On the other hand the 51 had worn out seals causing an air leak, but was still running with good compression. The same mix was used for both, so we can pretty much rule that out as the cause of the meltdown.
I think the majority of saw owners are guilty of two things, dull chains and no tuning skills. When things go sour for them they are left scratching their heads, and any saw can get labeled as junk. Autotune or Mtronic takes care of one, but it takes practice to sharpen a chain well, and most people just can't be bothered to take the time to learn. A good sharp chain makes it so much easier for a saw to do its job.

IMG_20211010_001559.jpgIMG_20211021_094259.jpgIMG_20211009_221113.jpg
 
Yes, I I think that a lean mixture may have contributed, who knows what the factory tune was. I'm betting the mixtures were never touched, the saw screamed neglect. I'm pretty sure though that this horrible chain contributed greatly to the overheating. I had to grind about a third of it off before it was usable again.
These cringe worthy saws both came from that owner, the cylinder on the 570 look to have had very little time, and the crank seals were good. On the other hand the 51 had worn out seals causing an air leak, but was still running with good compression. The same mix was used for both, so we can pretty much rule that out as the cause of the meltdown.
I think the majority of saw owners are guilty of two things, dull chains and no tuning skills. When things go sour for them they are left scratching their heads, and any saw can get labeled as junk. Autotune or Mtronic takes care of one, but it takes practice to sharpen a chain well, and most people just can't be bothered to take the time to learn. A good sharp chain makes it so much easier for a saw to do its job.

View attachment 1034459View attachment 1034460View attachment 1034461
Many guys are intimidated by sharpening. An Oregon roller guide makes it pretty easy to make a serviceable chain.
 
I just finished polishing the cylinder for a MS661 that had a beyond scored piston. About an 1/8 inch radius of the exhaust side top of the piston was gone. Ideally one would replace the top end, but that is $425 . I couldn't get every trace of scratch out, but if I go any further I will run out of plating I'm afraid. The perfect is the enemy of the good sort of thing.

Not the point of this though. The intake boot, manifold , whatever you want to call it was in half. Dull chain, long bar, trying to get finished I suppose.

This is a $1500 saw being operated by a pro, and he can't hear that difference in RPM. Surely it lost power.

Makes you scratch your head.
 
I just finished polishing the cylinder for a MS661 that had a beyond scored piston. About an 1/8 inch radius of the exhaust side top of the piston was gone. Ideally one would replace the top end, but that is $425 . I couldn't get every trace of scratch out, but if I go any further I will run out of plating I'm afraid. The perfect is the enemy of the good sort of thing.

Not the point of this though. The intake boot, manifold , whatever you want to call it was in half. Dull chain, long bar, trying to get finished I suppose.

This is a $1500 saw being operated by a pro, and he can't hear that difference in RPM. Surely it lost power.

Makes you scratch your head.
Next time use acid. It won't remove the plating like sanding can.
Provided you don't have gouges above the exhaust port you will probably be ok.
Stihl 661 cylinder and piston kit can be had for $289 on Ebay.
 
I have only vintage Stihl saws. 031, 041, and 075's. All said, 'do not use high octane fuel'. Now, fifty years later, is what we know at the pump as 'high octane', similar in any way to the old gasoline? We all know the issues with ethanol, so I only run 'high octane' now. Am I helping my saws or are they slowly committing suicide by fuel? Oil, I mix 32:1 with high test gas and keep it two months, then it goes in the Ford.... I drain the saws, then start them, warm, to eliminate fuel in the system. Good or bad?
God bless
That's another myth that never dies the one about high octane fuel burns slower and makes less power lol
High octane is fine to use in saws only downside is it usually costs more. The flame front burns just as fast as low octane and sometimes depending on the fuel high octane can have a faster burning flame front. The only thing high octane does different is having a better resistance to detonation it does not contain less "powers" as the myth would have us believe.
 
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