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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.

Why Do I Need To Change My Oil?

What Happens to oil Making Me Needing to Change It?

Regardless of its quality, every motor oil eventually loses its potency and must be changed to ensure peak engine protection. Let’s take a look at what happens to motor oil over time and why you periodically need to change oil.

Losing the base

Base oils are the backbone of the finished lubricant that ends up in your engine. Over time, they lose effectiveness due to the following factors:

Oxidation

The interaction between oxygen molecules and motor oil molecules naturally leads to chemical breakdown.

Just as oxygen causes a cut apple to brown or exposed metal to rust, it breaks down base oils and reduces motor oil’s effectiveness.

Oxidation can lead to increased oil viscosity, which negatively affects energy efficiency. It also causes the formation of harmful deposits and sludge.

High heat

Today’s engines run hotter than ever before, with temperatures up to 235°F (113ºC), and even higher if towing or hauling.

The rate of oxidation for oil doubles for every 18°F (10°C) increase in temperature.

Moisture

Your vehicle is subjected to temperature swings, even when it is parked in the garage.

Those temperature swings cause condensation to form inside your engine, leading to water contamination.

Leaving a vehicle parked for extended periods or taking short trips that don’t allow the engine to fully warm up allow water to remain in the oil rather than evaporating and exiting through the tailpipe. Water can lead to formation of sludge…yet another reason why you must change oil.

Viscosity is a motor oil’s most important property. The lower the viscosity, the faster the oils flows, like water. Thicker oils flow more slowly, like honey.

Viscosity loss

A lubricant’s viscosity is its most important property.

Viscosity has a direct bearing on wear protection, and your engine is designed to operate best using a motor oil of a specific viscosity (e.g. 5W-30).

The intense pressure the oil bears as it’s squeezed between moving parts, like the piston ring/cylinder wall interface, can tear apart, or shear, its molecular structure, leading to viscosity loss.

Suddenly, the 5W-30 motor oil your engine was designed to use is now essentially a 5W-20 oil, and wear protection may be compromised. When this happens, it’s time to change your oil.

Fuel dilution

Fuel can wash past the piston rings and contaminate the motor oil, causing it to lose viscosity.

Frequent short trips that don’t allow the oil to reach normal operating temperature can be especially problematic because the fuel won’t volatilize and exit through the PCV system.

Excessive fuel dilution leads to sludge and varnish, requiring you to change oil more frequently.

Additives: Additives are added to base oils to reduce destructive processes and enhance beneficial properties.

For example, antioxidant additives help slow the rate of oxidation. Detergency additives help prevent deposits and sludge while cleaning pre-existing deposits. Formulators add anti-wear additives to some lubricants to form a sacrificial barrier on metal components and help prevent wear.

Since they’re sacrificial in nature, additive depletion is one of the primary reasons motor oil loses its effectiveness and must be changed. 

While AMSOIL synthetic motor oil gives you the convenience of fitting oil changes into your schedule, it remains vital to install fresh oil at the appropriate time.

A closer Look At Engine Sludge

Preventing Causes of Engine Oil SLUDGE

Brands matter, quality matters and frequent oil changes will not alter this. It’s all based on the additive quality and it does effect the price.

Engine sludge occurs when oxidized oil and contaminants build up on engine surfaces. It can restrict the flow of oil to the point of engine failure and costly repairs.

As the oil installed in your vehicle ages, oxygen reacts with the lubricant, resulting in a permanent chemical change. The oil picks up oxygen and becomes thicker. Just like oxygen attacks metal surfaces and causes corrosion, it negatively affects lubricants and reduces their ability to lubricate, cool and protect components. Excessive heat speeds the oxidation process. In fact, every 18°F (10°C) increase in temperature doubles the rate of oxidation.

Adding to the challenge, contaminants begin to form during normal operation. In engines, hot combustion gases can blow by the piston rings and contaminate engine oil. Glycol from engine coolant, water that forms with temperature fluctuations and fuel are other common contaminants that affect lubricants. Left unchecked, contaminants accelerate chemical reactions, which overload the lubricant and cause the formation of sludge – a gelatinous substance that wreaks havoc in engines.

Sludge can block the oil passages and oil-pump pick-up screen, resulting in oil starvation. Often, the negative effects are cumulative rather than sudden. Many engines with variable valve timing (VVT) use oil pressure-operated mechanical devices to change valve timing, duration and lift. Sludge can plug the solenoid screen or oil gallies and impact the operation of VVT mechanisms, eventually leading to a costly repair bill. Sludge reduces efficiency and increases time and money spent on maintenance.

Signature Series vs. Sludge

Signature Series Synthetic Motor Oil was subjected to the Sequence VG test to measure its ability to prevent sludge. As expected, Signature Series produced an oil pick-up tube screen virtually free from sludge (see image below). Our unique combination of detergents and high-quality base oils control oxidation and sludge to keep engines clean and efficient.

AMSOIL synthetic lubricants not only resist oxidation and sludge formation, they can help clean existing deposits in neglected engines due to superior detergency. With modern engines and equipment demanding higher-quality lubricants, it’s good to know AMSOIL synthetic lubricants are formulated to protect against sludge in the toughest operating conditions.

Sludge: a gelatinous substance that wreaks havoc in engines.

 

 

 

 

Signature Series has 50 percent more
detergents¹ to help keep oil passages clean and promote oil circulation. It provides 90% better protection against sludge².

 

 

Synthetic Warehouse note:

We own an ecoboost engine (on our Ford van) so based on our personal experience the Signature Series is the only choice in these engines. They run extremely hot effecting the process mentioned above. Test the oil you are using now at or near Ford’s maximum interval and I’m certain it’s beyond it’s life!! TBN and Oxidation levels can be at dangerous levels.  Signature Series gives you that extra benefit of the doubt because when the detergents dissipate you can start to have severe wear from corrosion and of course needless deposits from sludge AND increased oil consumption. We eliminated 75% of a resent F150 Ecoboost V6 oil consumption problem using the Engine Flush (FLSH) and the Signature Series 5W-30 (ASL).

It’s not just about keeping your car or truck longer. It’s the issues our competition causes such as carbon coating your intake valves which is an issue on modern gasoline direct injection engines.  It’s very costly to clean these as there is no-longer the gasoline we enjoyed as the cleaning agent. Fuel is shot directly into the quench area so oil vapors land on valves and build up over time.
Some newer cars do have an additional injector in the throttle body for start-up and cleaning but this will not be the common setup.

So AMSOIL Signature series will keep these areas cleaner as that’s part of what you are paying for. AMSOIL’s lowest volatility is by far worth paying for. And in some cases you pay less for our product than several of the “so called synthetics”.

Make our Sioux Falls locations your only source for lubricants! Many have made the switch for good. We’re at 47073 98th St just behind Marlins Diner. Exit 73 on I29. Or call to make sure I’m there at 605-274-2580.

 

Five reasons to use motorcycle oil in your bike

You can use Car Motor Oils in your Bike if you Add Two More Wheels.

You wouldn’t want to buy a used bike if motorcycle oil wasn’t used.

Impressive performance happens when you are using the right oil in the right application.

Len Groom | TECHNICAL PRODUCT MANAGER, POWERSPORTS

The results of a study from lubricant additive manufacturer Infineum caught my eye recently. A survey of 1,000 bikers revealed that fewer than 60 percent are using a motorcycle specific oil in their motorcycles. Interestingly, more than three quarters of respondents think they’re using a motorcycle oil. Clearly there’s confusion in the market that requires clarification.

Let’s start with why you should always use motorcycle oil in a motorcycle engine. I’ll boil it down to five key reasons.

1) Motorcycles run hotter

In general, automotive engines are water-cooled. A typical automotive engine can reach 235ºF (113ºC) during operation, which is plenty hot. Motorcycles, however, run even hotter, particularly big, air-cooled V-twins, like your average Harley Davidson. They rely on air flowing across the engine for cooling, which is inherently less efficient at dissipating heat. This configuration poses additional challenges in stop-and-go traffic when there’s little airflow, particularly on hot summer days. In fact, testing of a 2012 Harley Street Bob in our mechanical lab demonstrated an average cylinder head temp of 383ºF (195ºC).

Heat that intense causes some oils to thin and lose viscosity, which reduces wear protection. High heat also hastens chemical breakdown of the oil (called oxidation), which requires you to change oil more often. In extreme cases, the bike’s temperature sensors can shut down the engine if it gets too hot.

2) High rpm destroys lesser oils

Motorcycles tend to operate at engine speeds significantly higher than automobiles. Your average metric sport bike easily eclipses 10,000 rpm. Some have even pushed 20,000 rpm. Your car or truck’s redline doesn’t even come close. The hydrocarbon chains get ripped to shreds.. You can feel the after-effects through the peg and handle bars.

High rpm places additional stress on engine components, increasing the need for wear protection. It subjects oils to higher loading and shear forces, which can rupture the lubricant film and reduce viscosity, both of which increase wear. High rpm also increases the likelihood of foaming, which can reduce an oil’s load carrying ability, further inviting wear.

3) Increased power density = increased stress

Motorcycle engines produce more horsepower per cubic inch than automobiles. They also tend to operate with higher compression ratios. Increased power density and compression lead to higher engine temperatures and increased stress. This places greater demands on motorcycle oil to fight wear, deposits and chemical breakdown.

4) Must also protect transmission – prevent viscosity loss

Many motorcycles have a common sump supplying oil to both the engine and transmission. In such cases, the oil is required to meet the needs of both the engine and the transmission gears. Transmission gears can shear the oil as it’s squeezed between gear teeth repeatedly at elevated rpm, causing some oils to lose viscosity. Many motorcycles also incorporate a wet clutch within the transmission that uses the same oil. Motorcycle wet clutches require a properly formulated lubricant that meets JASO MA or MA2 frictional requirements.

5) Storage invites corrosion

Whereas automobiles are used almost every day, motorcycle use is usually periodic and, in many cases, seasonal. These extended periods of inactivity place additional stress on motorcycle oils. In these circumstances, rust and acid corrosion protection are of critical concern.

While a good passenger car motor oil (PCMO) hits many of these performance areas, it doesn’t get them all.

PCMOs usually contain friction modifiers to help boost fuel economy. Furthermore, PCMOs don’t meet JASO MA or MA2 requirements. If used in a motorcycle, they can interfere with clutch operation and cause slippage. And no rider wants to deal with a slipping clutch. Likewise, motor oils have no natural rust or corrosion resistance. Instead, corrosion inhibitors must be added to the formulation, and typical motor oils don’t contain them.

AMSOIL Synthetic Motorcycle Oil is designed for the unique demands of motorcycles. It’s formulated without friction modifiers for precise, smooth shifts. It also contains a heavy dose of corrosion inhibitors to protect your engine against rust during storage. And it’s designed to resist viscosity loss due to shear despite intense heat and the mechanical action of gears and chains.

Ensure your customers are using AMSOIL synthetic motorcycle oil in their bikes for the best protection this riding season.

And people who use car oil in their bikes probably use the term “drive” when referring to riding.