Why is it so difficult to detect varnish potential with traditional fluid analysis techniques?

Let’s start with a brief explanation of what varnish is made of and how it forms. Varnish deposits are made up of lubricant degradation by-products. Lubricant degradation occurs from oxidative, thermal or chemical attack on the building blocks of the lubricant – the hydrocarbon molecule. Hydrocarbon degradation is a complex process where normal oil molecules transform into a wide variety of harmful intermediaries. These intermediaries are highly reactive and easily transform into new compounds. As these reactions continue or propagate, new polymers of increasing molecular weight form. Many of these compounds or by-products are insoluble. Simply put, varnish is composed of these organic polymers.

Conventional laboratory test methods are not intended to identify these by-products. What conventional oil analysis does do is identify the end result of certain physical properties, contamination and component wear.

QSA® focuses specifically on the chemical and physical signatures of the particular types of degradation by-products that have a high tendency to deposit on surfaces.

QSA®, is concerned with elements in transition, degradation by-products that are on the way to becoming something else – varnish. Finding those elements in the oil is a complex and difficult task. One way to look at it is this is a natural evolution of the science of lubrication analysis and we are the laboratory at the leading edge of the research.