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Why are There Different Two-Stroke Oil Mix Ratios for Chainsaw Oil

Why are There Different Two-Stroke Oil Mix Ratios for Chainsaw Oil

Swamp mix.

That’s what you call a concoction of two-stroke oil and gas that’s been slopped together with no measuring tools and no regard for engine protection. Your chainsaw or string trimmer could be running on a 50:1 mix. Could be 72:1. Could be 147:1. There’s no telling.

I often made swamp mix back in the day. Like other adherents to the dark art of mixing foul-smelling liquids in a dimly lit shed, I did it for a couple reasons: 1) I didn’t have clearly marked measuring containers at the ready, and 2) even if I had, I wouldn’t have felt like playing chemist with my chainsaw when I’d rather be cutting brush.

I never blew up a saw doing this. But, then again, I’m not a professional logger, so I didn’t cut often.

Some people don’t like mixing two-stroke fuel/oil because it’s a mess. Some hate it because math makes their brain hurt.

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What is a two-stroke mix ratio?

The math isn’t that tough to understand. Say your chainsaw manufacturer recommends a 50:1 fuel/oil mix. This simply means you need 50 parts of gas to one part two-stroke oil. Two-stroke engines derive lubrication from the oil mixed directly into the gasoline, unlike your car engine, which lubricates itself with oil housed in an oil sump and circulated by an oil pump.

Complicating things, some equipment manufacturers recommend different mix ratios. While most modern trimmers, chainsaws, leaf blowers and the like call for 50:1, some older equipment recommends 32:1. If you have multiple pieces of equipment with different mix ratios, you have to mix and store multiple cans of fuel. That’s not only a hassle, it’s a situation begging for problems when you accidentally dump 50:1 in your saw that takes 32:1.

This scenario likely isn’t a problem for landscapers, loggers and other professionals who replace their equipment often due to heavy use. But plenty of homeowners still use older equipment that calls for a richer fuel mixture.

Life would be much easier if every manufacturer recommended the same mix ratio, right?

They don’t. But we do.

AMSOIL SABER Professional Synthetic 2-Stroke Oil is tested and proven at any mix ratio up to 100:1. That means you can mix one can of fuel and use it in all your two-stroke equipment. Done. Problem solved. If you want to use 50:1, use that. Or 80:1. For best value, use 100:1. You could mix at 71:1 if you want. It’s up to you.

And, to eliminate the hassles of mixing fuel, we offer bottle sizes matched to certain sizes of gas cans. For example, to mix AMSOIL SABER Professional at 50:1 in a 2.5-gallon gas can, just use an entire 6.4-oz. bottle. Use half the bottle for a 100:1 mix ratio.

That’s the ratio I now use in my chainsaw. As the piston images show, SABER Professional mixed at 100:1 outperforms other two-stroke oils at 50:1, fighting power-robbing deposits and maintaining operability.

AMSOIL SABER Professional mixed at 100:1 delivers better protection against power-robbing deposits than other oils mixed at 50:1.

With SABER Professional you spend less on oil, get better protection and eliminate hassle when mixing fuel. And you never have to make swamp mix again.

Saber Pro 100:1 is in stock at Sioux Falls, Stan Houston’s location

What Causes Engine Oil Oxidation?

The Dynamics of Engine Oil Oxidation

You guessed it, the key ingredient to engine oxidation is oxygen.

Oxygen comprises about 20 percent of our atmosphere. It’s the third most common element in the universe. Without it we’d all be doomed.

And yet too much of it can cause problems inside your engine.

What is oxidation?

Oxidation occurs when the addition of oxygen changes a chemical substance. Take an apple, for example. Everyone knows that oxygen will quickly cause a cut apple to turn brown. Or metal. Oxygen can cause rust to form on some metals in a matter of days. Have you ever noticed your brakes grinding after having left your car sit for a couple days in wet weather? That sound is your brake pads scouring rust from the rotors. Never worry about that one as driving soon burns that off..

brake rotors oxidized from sitting or oxygn.

More wear on or in your engine occurs during storage. The oxidation discussed below can be detrimental. And that is not limited to the motor oil but the coolant system as well.

Motor oil isn’t immune to oxidation. As oil reacts with oxygen, a permanent chemical change occurs that causes oil molecules to lose one or more electrons. This can result in several problems, including…

  • Formation of sludge and deposits that reduce engine efficiency and increase the risk of engine failure
  • Increased oil viscosity, which reduces fuel efficiency
  • Additive depletion, reducing the oil’s effectiveness
  • Accelerated degradation, causing you to change oil more often

Heat accelerates oxidation

Every 18ºF (10ºC) increase in temperature doubles the rate of oxidation. That doesn’t bode well for motorists driving modern turbocharged vehicles that create increased heat compared to older vehicles. Or that Harley waiting in lines of traffic at events when block temps exceed 400F.

Heat isn’t the only oxidation accelerant – certain metals, acids and water can also hasten oxidation. So can large volumes of entrained air, known as foaming.

Can we prevent motor oil oxidation?

Unfortunately, no. Nature is a relentless force, and all motor oil will eventually oxidize to some degree. But we can dramatically slow oxidation through use of synthetic base oils and quality oxidation-inhibitor additives.

AMSOIL synthetic lubricants are formulated using base oils with a saturated molecular structure, meaning oxygen is prevented from attaching. This provides inherent heat and oxidation stability compared to unsaturated conventional oils.

And, because AMSOIL synthetic lubricants don’t contain contaminants like conventional oils, their base composition doesn’t accelerate oxidation.

AMSOIL synthetic lubricants also contain high-quality oxidation inhibitors. These additives are sacrificial in nature, meaning they’re designed to deplete over time. Because AMSOIL synthetic lubricants have inherently better oxidation resistance, their oxidation inhibitors last longer since they don’t deplete as rapidly.

When components and additives are selected for blending, cost is never a deciding factor thus our formulations will always result in the best of class. As AMSOIL does not have stock holders there are no outsiders to effect our decisions to always use the very best.

So, what does that mean to me?

That all adds up to a motor oil that…

  • Lasts longer despite intense heat and stress
  • Helps keep your engine cleaner and more efficient
  • Saves money in the long run through reduced maintenance
  • And as a bonus you enjoy added performance

So, while oxygen lets you breathe, AMSOIL synthetic motor oil lets you breath easy since your engine is protected against oxidation.