Measurement of Lubricating Oil Consumption

Kent Froelund, Hannu Jääskeläinen

Abstract: Techniques developed to measure engine lubricating oil consumption rely on direct measurement using gravimetric or volumetric methods, or on inference tests by measuring the quantity of a tracer in the exhaust gas. Laboratory oil consumption instruments have been developed that utilize both types of methods.

Introduction
Direct Measurement Techniques
Tracer Methods

Introduction

Experimental, laboratory measurement of engine oil consumption is carried for a wide range of reasons. Engine and engine component manufacturers measure the lubricating oil consumption in their new product designs prior to final production to ensure design objectives are met. Lubricant and additive manufacturers measure the effect of their products on oil consumption in a range of engine tests to ensure that their products do not lead to excessive oil consumption.

Over time, many different techniques have been developed to measure oil consumption. These techniques generally use one of two approaches to experimentally quantify oil consumption:

Direct measurement using gravimetric or volumetric methods, or
Inference based on measurements of the quantity of a tracer in the exhaust gas.

In the latter approach, the tracer must be either unique to lubricating oil or present in such quantities that interference from other sources can be neglected or easily accounted for.

A number of laboratory oil consumption instruments have been developed and are commercially available that utilize one of these methods. The same instruments and methods can be typically used to measure oil consumption in both diesel and gasoline engines.

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