Why do we need ZINC

Apr 7, 2014 | additives, Engine Oil, Techenomics

Do you own an older engine like I do?
Do you have an old model car you have done up?
Maybe an old inboard boat motor?

If you answered yes to any of these questions then I am sure you already know how to look after your pride and joy. But just to make sure, you should read the following information in this article, It will explain why we need Zinc in our oil. If you purchase your oil from a local retail store than you could be putting your pride and joy in jeopardy.

Modern engine oils contain very little amounts of zinc because of API and ACEA regulations. The stringent controls on emissions have caused the additive to be minimised due to the amount of pollutants it admits into our atmosphere. The additive also effected some of the emission control components such as catalytic converters.


The image above indicates what can go wrong and will go wrong should your oil contain the incorrect amount of Zinc and phosphorous.

The parts are from a 302 Chevy Inboard Boat Motor. The engine was dusted after using an oil that contained insufficient amounts of Zinc.

So what is Zinc additive?
Zinc dialkyldithiophosphates are referred to as ZDDP. There are three different types of Zinc additives that may be used in the oil manufacturing process, primary, secondary and ary. The secondary type ZDDP provides greater antiwear protection and hydrolytic stability but has less thermal stability. Whereas the Ary type ZDDP is suppose to provide excellent thermal stability but less effective in antiwear protection and hydrolytic stability. So don’t think just because your oil contains Zinc it will keep you in the clear.

Just to confuse you, there is also ZnDTP, ZDTP and ZDP.

What are the benefits of using a high Zinc oil?
Zinc additive react under heat and load. It creates a protection barrier over metal surfaces to protect them from metal to metal contact. They provide control over oxidation and corrosion by preventing valve train and bearing corrosion.

So how much Zinc do we need?
Well this really does depend on the valve train pressure. Most racing engine oils contain adequate amounts of Zinc and this is all you need to maintain and ensure you have a healthy engine. The best approach for any pride and joy is to have the oil analysed, this will give you peace of mind and highlight any issues if they exists.

Ensure your oil does not contain too much Phosphorous as it will clean away the Zinc build-up on the metal surfaces, diesel engine oils can do this.

Have your virgin oil tested and find out how much Zinc, Phosphorus and Molybdenum is really in it.

For further information on Zinc, contact Techenomics for assistance.

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