ASTM_DS57-1975.pdf

LOW-TEMPERATURE PUMPABILITY CHARACTERISTICS OF ENGINE OILS IN FULL-SCALE ENGINES#Prepared by the Data Analysis Panel of ASTM Committee D-2 R&D Division Vll-C on Non-Newtonian,Low-Shear Phenomena ASTM DATA SERIES PUBLICATION 57 List Price$16.00 05-057000-12 AMERICAN SOCIETY FOR TESTING AND MATERIALS 1916 Race Street,Philadelphia,Pa.19103 by AMERICAN SOCIETY FOR TESTING AND MATERIALS 1975 Library of Congress Catalog Card Number:75-24603 NOTE The Society is not responsible,as a body,for the statements and opinions advanced in this publication.Printed in Long Island City,N.Y.September 1975 Data Series DS 57 American Society for Testing and Materials Related ASTM Publications Multicylinder Test Sequences for Evaluating Automotive Engine Oils,STP315F(1972),$8.25,04-315060-12 Shear Stability of Multigrade Crankcase OilIP Fleet Tests,DS 49-S1(1974),$4.00,05-049001-12 Single Cylinder Engine Tests for Evaluating Performance of Crankcase Lubricants,STP 509(1972),$5.00,04-509000-12 Editorial Staff Jane B.Wheeler,Managing Editor Helen M.Hoersch,Associate Editor Charlotte E.Wilson,Senior Assistant Editor Ellen J.McGlinchey,Assistant Editor SUMMARY Low-temperature engine oil pumpability data have been obtained on thirteen ASTM Pumpability Reference Oils in seven full-scale test engines.Border-line Pumping Temperatures based on gallery oil pressure traces were deter-mined for all thirteen Reference Oils in four of the test engines,and for nine of the Reference Oils in all seven test engines.Data were also obtained as to the type of flow failure occurring(air-binding or flow-limited)and on rocker arm oiling times.The results indicate substantial differences in pumpability among both test oils and test engines.Possible reasons for these differences are analyzed,and a model,based on engine oil pump inlet system dimensions,is proposed.This model accounts for some of the differences found in engine severity and the type of flow failure which occurs.The pumpability data reported should provide the basis for development of a laboratory bench test to predict engine oil pumpability.Results from various bench tests and engine pumping rigs and their correlation with the full-scale engine data will be summarized in a later report.INTRODUCTION AND BACKGROUND The current ASTM Committee D-2 Research and Development Division VII-C Task Force Program to evaluate the low-temperature pumpability properties of thirteen ASTM reference oils in seven full-scale test engines,five engine pumpability rigs,and a variety of bench tests was initiated at the request of SAE.In 1970,a Task Group of SAE Fuels and Lubricants Subcommittee 2 completed an inquiry to determine the extent of the low-temperature pumpability problem.Based on the results of the survey,Subcommittee 2 requested(1)*ASTM to develop a simple laboratory test to measure the ability of an oil to flow to the engine oil pump inlet in a manner relatable to engine conditions,and to consider the relationship between low-temperature oil properties and the supply from the pump to critical engine parts.In response to the SAE request,ASTM Task Force members conducted ex-ploratory tests in engines,engine pumping rigs,and laboratory bench rigs in an effort to obtain enough information to design a comprehensive coop-erative program.The ASTM Task Force concluded early in the program that they would have to obtain extensive full-scale engine data to serve as the basis for evaluating the ability of bench tests and engine pumping rigs to predict engine oil pumpability.*Numbers in parentheses designate References at end of report.DS57-EB/Sep.1975Copyright 1975 by ASTM International www.astm.org A literature search conducted early in 1970 revealed that no usable engine pumpability data existed.In 1961,R.G.Moyer(2)conducted tests on an automotive oil pump rig.His results showed that pumping failures occurred by air binding,and that an oils pumpability in his rig could not be predicted by its 0F(-17.8C)viscosity,ASTM Pour Point,or channel point.In 1963,T.W.Selby(3)evaluated the pumpability problem and concluded that existing shear rates in different parts of the engine and the vis-cosities of the Vl-improved oils at the existing shear rates determined where the oil failed to flow fast enough to satisfy the engines demands.The first-engine results were reported in 1971 by Smith and Graham(4),who showed that rocker arm oiling times could not be predicted by ASTM Pour Point,Brookfield viscosity,or Cold Cranking Simulator viscosity.They found that some used oils were more pumpable than new oils and that engine design was an important factor in pumpability.Boone,Crouse,and McLaughlin(5),however,found some indications that a tilt-can pour test could be used to predict an oils rocker arm oiling time,but found no correlation between polymer type and low-temperature fluidity.In 1972,Stewart and Spohn(6)motored an engine at 1650 rpm in a cold room at 0F(-17.8C)and-20F(-28.9C)using twelve commercial oils and nine labo