SYMPOSIA PAPER Published: 01 January 1973

Factors Affecting the Formulation of Engine Oils for LP-Gas Service


The problems associated with crankcase oils for engines using liquefied petroleum gas as a fuel are largely those involving oxidation and excessive ash. Engine oils for propane or natural gas service, therefore, must be formulated to control combustion chamber deposits which may promote preignition and spark plug fouling and to resist oxidative deterioration. These requirements define an LP-Gas engine oil composition as a virtually ashless product with excellent oxidation stability. Generally, since propane/natural gas fuels produce no liquid byproducts to act as a temperature quench and, in addition, burn cleanly and completely, combustion temperatures are high.

Fuel combustion properties and other factors such as exhaust blow-by determine the performance characteristics needed by LP-Gas engine oils as: superior dispersancy for oil oxidation products, high-temperature oxidation inhibition, rust protection, antiwear and extreme pressure (load carrying) qualities, and pour-point depression.

The details of an additive system supplying these performance properties is given. The proposed formulation has Supplement I compounding and satisfactorily meets the service requirements of both automotive and high, medium, and slow speed industrial engines.

Author Information

Broman, V., E.
Research and Development, Atlantic Richfield Co., Harvey, Ill.
Price: $25.00
Contact Sales
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Developed by Committee: D02
Pages: 3–17
DOI: 10.1520/STP44732S
ISBN-EB: 978-0-8031-6043-9
ISBN-13: 978-0-8031-6197-9