Winter (Cold) flow wear factors in your engine

Engineers agree that most engine wear occurs during cold starts. While the exact percentage depends on several factors and is difficult to define, the reasons include the following…

A richer air/fuel mixture at startup washes oil from the cylinder walls
Condensation forms inside the engine that causes rust and corrosion
Cold piston rings and cylinders don’t seal as well, causing combustion gases to “blow by” the rings and contaminate the oil
Gravity causes much of the oil to fall back into the oil sump, leaving components unprotected
Cold oil doesn’t flow immediately at startup, temporarily starving the engine of oil

While all these factors are important, lack of oil due to poor cold-flow properties is the biggest culprit. Fortunately, there’s something you can do about it.

“Cold” isn’t just for winter

First, it’s important to define a “cold” start. While true that oil thickens more in sub-zero winter weather and causes increased starting difficulty, an engine is considered “cold” after it’s sat long enough to cool to ambient temperature, typically overnight. Even in warm climates, cold-start wear is a problem.

The oil inside your engine cools as it sits overnight. As it cools, its viscosity increases (it thickens). When it’s time to start your vehicle in the morning, the thicker oil doesn’t flow through the engine as readily as it does when it’s at operating temperature. It’s during this time that vital engine parts can operate without lubrication, increasing wear.

The problem is more pronounced the colder it gets, particularly if you’re using conventional motor oil.

Waxes solidify in the cold

Conventional lubricants contain paraffins, or waxes, that solidify when the temperature drops. These waxes cause the oil to thicken. In the comparison shown here, we cooled a conventional oil and AMSOIL Signature Series 5W 30 Synthetic Motor Oil (ASL) to -40ºF. The conventional oil on the left thickened so much it barely flowed from the beaker. If that oil were inside your engine on a cold morning, it could prevent the crankshaft from spinning fast enough to start the engine, leaving you stranded. Even if the engine started, you wouldn’t be out of the woods. Thick, cold oil can fail to flow through the tiny screen openings on the oil pickup tube (see facing page), starving the engine of oil for several vital moments before the oil begins to heat up and flow throughout the engine.

In addition, thick oil can fail to flow through the tiny passages in the crankshaft to lubricate the main bearings. Similar oil passages in the camshaft ensure the engine’s upper end is lubricated (see facing page). The further away from the oil pump these oil passages reside, the longer it takes the oil to reach components at startup, placing your engine at increased risk of wear.

Poor lubricant cold-flow properties can also affect variable valve timing (VVT) systems. Engines equipped with VVT have solenoids with tiny openings through which the oil flows and acts as a hydraulic fluid to actuate VVT components. The solenoid pictured to the right, from a Ford* 3.5L EcoBoost* engine, contains openings .007 inches across – about the thickness of two sheets of paper. Oil that fails to flow through these tiny passages reduces VVT performance and can trigger a check-engine light.

Here’s how to protect your engine

AMSOIL synthetic motor oils provide better cold-flow properties than conventional oils. Our synthetic base oils don’t contain the waxes inherent to conventional oils. As a result, they demonstrate reduced pour points and provide increased fluidity during cold starts. This translates into oil that flows almost immediately through the oil pickup screen and other tiny oil passages when you start your engine, protecting it against wear.

Look at the oil’s pour point to gauge its ability to flow quickly at startup, typically reported on the oil’s data bulletin. Pour point is the coldest point at which an oil will flow. Lower values equal improved cold-flow and maximum wear protection. AMSOIL Signature Series 5W-30 Synthetic Motor Oil, for example, provides a pour point of -50ºF (-58ºC).

Pique prospects’ curiosity

This type of information can help you create curiosity about AMSOIL products and lead someone from not looking for lubricants to looking for AMSOIL products. Ask pointed questions or provide useful information, such as…

Most engine wear occurs during cold starts. Do you take steps to guard against start-up wear?
Even in warm climates an engine is considered “cold” after it’s sat overnight.
Do you ever have trouble starting your truck on cold mornings?

Once they’ve shown interest, offer more technical explanation if required and offer AMSOIL synthetic motor oil as a solution to difficult cold starts and accelerated cold-start wear.

A little known fact

The differences in brands comparing a 5W-30 to the protection of a 10W-30 or 0W-30 can even be critical to the prevention of wear in the 50 to 65 degree F range. So just because you may live in a southern climate doesn’t mean you are in the green with a older specification viscosity.. A more advanced oil brand allows you to take advantage of the tech of the latest (lowest allowable) start-up viscosity year round.

Engine Sludge Is Easily Avoidable

John Baker & Associates |Jul 24, 2019 4:20 PM

Engine sludge.

It’s a back gelatinous substance that wreaks havoc in engines. And long before the engine’s demise, engine sludge can foul engine sensors and interfere with performance. Some mechanics call it the “black death.”

How does motor oil, which is fluid, become a semi-solid paste or gel inside an engine?

Here’s what we’ll cover:

How engine sludge forms
The effects of engine sludge
Synthetic oil helps prevent engine sludge
High-quality additives fight engine sludge
Severe service invites engine sludge

How engine sludge forms

Engine sludge is the result of a series of chemical reactions.

The lubricant degrades as it is exposed to oxygen and elevated temperatures. The higher the temperature, the more rapid the rate of degradation. In fact, every 18°F (10°C) increase in temperature doubles the rate of oxidation.
Many people still believe any oil is fine as long as you change it often but 95% of the brands out there do not address that inch of protection when you really need it!! We’ve all had issues where the engine is overheating or some situation where adequate lubrication isn’t available. AMSOIL offers 75% more protection when you need it and our diesel oils offer 6X more protection than required by industry testing.

The by-products of this reaction form highly reactive compounds that further degrade the lubricant. Their by-products react with other contaminants, forming organic acids and high-molecular-weight polymeric products. These products further react, forming the insoluble product known more commonly as sludge.

What begins as a thin film of lacquer or varnish deposits on hot or cold metal surfaces and bakes into an expensive mess.

The effects of engine sludge

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.

Who doesn’t want a cooler engine? Sludge, even the early stages prevents the engine from dispersing heat efficiently. Why would you risk a Group III “synthetic” which does leave deposits adding to or resulting into an engine which struggles to exhaust heat.

Synthetic oil helps prevent engine sludge

Fortunately, sludge and varnish deposits are something oil manufacturers can control. Using thermally stable synthetic base oils reduces the rate of degradation (oxidation). (Yes – and that is “Real 100%” Synthetics – not the ones they currently call “Fully”..

Anti-oxidant additives help reduce the rate of degradation as well. One of the most widely used is zinc dithiophosphate. Not only is it an excellent oxidation inhibitor, it is an outstanding anti-wear additive as well.

High-quality additives fight engine sludge

We can further address many of the issues occurring after the initial oxidation stage.

Additives, such as detergents and dispersants, are commonly part of motor oil formulation. They help promote the suspension of contaminants within the oil and keep them from agglomerating.

Detergents, which are also alkaline in nature, assist in neutralizing acids generated in the sludge-building process. Anti-oxidant, dispersant and detergent additives are consumed during use.

To achieve maximum life expectancy, use an oil with high concentrations of anti-oxidant, dispersant and detergent additives.

AMSOIL Signature Series Synthetic Motor Oil, for example, has 50 percent more detergents* to help keep oil passages clean and promote oil circulation. It provides 90 percent better protection against sludge**.

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

PDF of the test where AMSOIL has this done (Southwest Research)

Buy Signature Series

Severe service invites engine sludge

Equipment operating conditions also influence the likelihood of sludge or varnish issues.

Stop-and-go driving, frequent/long-term idling and operation in excessively hot or cold weather can increase the likelihood of sludge and varnish, especially if using more volatile conventional oils. If sludge has already formed, you can use an engine flush to clean sludge from your engine.

Interestingly, most auto manufacturers note in their owner’s manual that operation under any of the above conditions is considered severe service and requires more frequent oil changes.

From a mechanical standpoint, things like adding too much oil to the oil sump, antifreeze contamination, excessive soot loading, excessive oil foaming, poor engine-combustion efficiency, excessive blow-by and emission-control-system issues can all lead to the formation of sludge and varnish.

By practicing good maintenance and using properly formulated, premium synthetic lubricants, like AMSOIL synthetic motor oil, your vehicle won’t succumb to the “black death.”

Taking it a step further which many of our customers do – to make sure your vehicle is always running in peak condition one thing is to have your oil analyzed. I do it not so much to see how the oil is doing but to measure what may be going on in the engine to deplete detergents or to test for any out of typical wear levels, fuel in the crankcase, and to see if the viscosity is still on par. Oil analysis kits are easy to use especially when you have the dipstick extraction pump.

*vs. AMSOIL OE Motor Oil
**Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN PLUS specification.

Tag: variable valve timing

All You Need To Know About Motor Oil Cold Flow