Matt's Automotive

Oil Tips

Taking The Mystery out of Motor Oil

Motor oils do more than you think.

It's easy to name the prime function of motor oil: to lubricate every moving part of your engine with a protective film that reduces friction. But motor oil has at least 4 other duties, and failure to perform them all can seriously reduce the performance and life of your engine.

First, your motor oil cleans your engine. Gasoline and diesel engines can produce soot, ash, acids and moisture which form sludge, varnish and resins. If they collect on critical engine parts, it means serious trouble. A quality motor oil keeps them suspended until filtered out or drained away when you change your oil.

Next, oil seals microscopic hills and valleys on piston rings and cylinder walls. Without proper sealing action, you'll loser power and waste fuel.

Motor oil also protects your engine against rust and corrosion.

Finally, oil cools vital parts such as camshaft, rods and pistons that the engine coolant in your radiator cannot reach, As much as 40% of the cooling job in your engine is performed by oil in the crankcase.

MPistonMaking it easy to choose the proper oil.

With so much depending on your oils performance, it's important to select the right oil for your engine's needs. The API (American Petroleum Institute) Mark identifies oils which have passed a comprehensive series of performance tests and product quality audits. These tests verify the ability of the oil to perform virtually every task expected of it in your engine, from minimising engine wear to preventing corrosion and the build-up of deposits. By choosing oil with the API Certification mark, you can extend the life of your engine, reduce the chance of engine failure, and help maintain emission standards to fight pollution.

How to read a motor oil label.

All the information you need to know about motor oil is Contained in the API "donut" symbol shown here.

In the. centre of the donut is the SAE viscosity grade. Viscosity is a measure of an oil's flow characteristics at certain temperature. The first number/letter combination (5W) indicates how well oil will flow to lubricate critical engine parts at low temperatures, The lower this number this more easily will the oil help your engine start in cold weather. The second number (30) indicates the oilís ability to lubricate the engine at high temperature. In this case, the higher the number, the, thicker the oil. A multi grade oil, 5W-3O as in the example, satisfies the requirements of both viscosity grades. The 2-1etter code identifies the type of engine which the oil is to be used in, and the performance rating of the oil. íSí means the oil is suitable for gasoline engines ("C"' designates oil for diesels). "SJ" was introduced in 1996 and is currently the highest gasoline engine performance standard; it should be used in all current and earlier cars.

'"Energy Conserving II" means the oil is proven to reduce fuel consumption by approximately 2-7% in comparison with a standard reference oil.

Cold facts about viscosity index.

The Viscosity Index or V.I. measures the change of an oil's viscosity over a wide range of temperatures. The higher the VI of the oil, the less it will thicken when cold, and the less it will thin out when hot hence a high VI oil will be more effective when lubricating your engine over a wide temperature range.

Once you understand the SAE viscosity grades, you can choose the best oil for your needs. Here's a description of the five most common SAE multi-grade oils:
OW-20-. Premium winter grade oil. Provides year-round protection and fuel economy. Where SAE 5W-20 is recommended.

OW-30-. Premium winter grade oil. Provides year-round protection and fuel economy. Where SAE 5W-30 is recommended.

5W-30: Premium multi-grade oil for easier cold-weather starts, maximum protection, excellent fuel economy and added engine life. The preferred grade for cars built after 1989.

10W-30: The best-selling premium multi-grade. Delivers excellent all-round performance for the average driver.

10W-40: A premium multi-grade oil formulated for hotter-than-normal running conditions. Provides good fuel economy and extended engine life.

Making a change for the better.

Todayís engines are efficient and sophisticated machines, often using turbo-charged, multiple camshafts and other features . They also run faster and hotter, placing tremendous demands on motor oil performance.

That's why it is essential to follow a strict oil-and-filter-change schedule for your car, Changing the oil and filter remove harmful contaminants that may build up in your oil.

A fresh supply of oil with its specially selected additives will restore the protection your engine needs against corrosion , gum deposits, excessive wear and other problems. Generally,the oil and filter should be changed every 5,000 km. or 3 months, but check your Owners Manual to be sure.

Speaking of Performance additivesÖ

Most oils look, feel and smell the same but their performance can be vastly different, thanks in part to additives. Additives suspend dirt, inhibit foam, improve cold-weather flow, prevent corrosion, reduce friction and add other qualities.

Many speciality additives or oil treatments are sold separately as brand names and promise longer life or extra performance for your engine. Remember that modern engine oils are recipies with measured portions of ingredients. Upsetting the recipie balance could lead to problems.

An oil formula may include a little anti-wear additive the same way a cake recipe includes a pinch of salt to bring out flavour. If a little salt works, should you add more? Probably not, and the same goes for oil additives.

Promoting your carís engine and the environment.

If you change your oil yourself, please continue to help....
Don't dump used oil on the ground, down drains or in sewers, and donít mix it with any other liquid.
Do place used oil in a clean plastic container with a secure lid and take it to a collection point for disposal or recycling.

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