Power at Work: Don't delay those engine oil changes

Monday, March 2, 2009

Despite the advances in engine and lubrication technology, basic maintenance is still essential.
That means buying a high-quality oil of the correct type and viscosity and changing it and the filter regularly

by RALPH WINFIELD

Both engine and lubrication technology have advanced significantly in the last 50 years. Many of you, including myself, will remember when you changed the car or other engine oil at the equivalent of "1,000-mile" intervals. The reason was that the "mineral oil" of the day was carrying all the contaminants that it was capable of holding, and sludge was starting to form and build in the engine.

The 1950s brought forth new detergent oils that would actually carry more contaminant. Filters cleaned the oil every time it passed through the system. Engine oils have gone through many changes since then. But maintenance is still key to long engine life.

Many engines are blown before they reach 200,000 kilometres or 5,000 hours. In many cases, the problems are still created by lubrication shortfalls. Those are usually not the fault of the engine manufacturer nor the company formulating or supplying the engine oils.

Relatively speaking, engine oils and filters are cheap when compared to the price of engine replacement. If oil change intervals are pushed to the limit or ignored, you are courting disaster.

Engine oils carry even higher loadings of combustion contaminants and condensation than they did 50 years ago. If the oil (and filter) is not changed soon enough, contaminants will build up in the engine and go unnoticed until you do change the oil and filter. The new oil will pick up sludge contaminants and can still plug those oil passages that cause the same catastrophic engine failures of the earlier times.

Fleet owners with many engines do attempt to extend drain periods to save time and money. However, they monitor their overall costs very closely. In many instances, they have used oil samples analyzed to determine the levels and types of metallic particles in the oil. These are the indicators that the oil additives have been depleted and excessive engine component wear has started.

Please remember that we did not have high-speed devices like turbochargers on our engines 50 years ago. These items operate at very high speeds and very high temperatures. High quality, clean lubricants are essential for their survival.

In addition, the newer emission standards for engines have brought about many engine design changes.

The compression rings are higher up on the pistons, thus the lubricating oil (which also acts as a heat remover from the pistons) must be able to withstand much higher operating temperatures without breaking down.

Similarly, fuel injection pressures for the newer diesel engines have increased from the 5,000 to 7,000 psi range into the 20,000 to 25,000 psi range with the use of common-rail fuel delivery systems and electronic injectors. While the fuel spray is much finer for better combustion, the resultant soot particles are much harder and more abrasive. The lubrication system must handle this soot more effectively, but you as the owner/operator must get it out of the engine by changing the oil and filters at intervals not exceeding those recommended by the engine manufacturer or the lubricant supplier.

So, while engine and lubricant technology has advanced significantly over the last 50 years, some of the basic maintenance issues still need careful attention by engine owner/operators.

There are no magic solutions or potions to take the place of routine maintenance. Operator manuals do not recommend oil additives and neither do I. Buy a high-quality oil of the correct type and viscosity and change it and the filter regularly, as suggested by the engine manufacturer.

I own a 2006 car which has the recommended oil viscosity printed on the oil filter cap. It is 5W-20! Even 20 years ago I would not have believed that I would be owning an engine that requires a 5W oil to eliminate metal-to-metal contact during start up on a year-round basis.

We all must change our thinking – and our oil (and filters) – as required. BF

Agricultural engineer Ralph Winfield farms at Belmont in Elgin County.