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The optical spark plug probe and ionization head gasket probe developed at Sandia Laboratories were applied to one cylinder of a production multicylinder automotive gasoline engine. The purpose of this application is to eventually study combustion phenomena leading to high emissions under cold start and cold idle conditions. As a first step in studying cold start combustion and emissions issues, diagnostic instrumentation was simultaneously applied to a production engine under steady state idle, road load and an intermediate load-speed condition. The preliminary application of such instrumentation is the subject of the present paper. The spark plug probe was redesigned for ease of use in production engines and to provide a more robust design. The two probes were geometrically oriented to obtain radial line-up between the optical windows and ionization probes. Data were taken simultaneously with both probes at the three load-speed conditions mentioned above.

The SwRI/BMW N.A. Intake Valve Deposit Test procedure was the first performance-based test procedure adopted for fuels qualification in the United States. The initial fuel evaluations were begun in January 1988 with six 1985 BMW 318i vehicles. Since that time, the fleet has grown to include over 60 BMW cars, and more than 2000 tests have been performed. This paper gives a statistical summary of approximately 1800 tests performed over a four-year period. Performance data and possible sources of test variation are discussed. Data and analyses offered represent results of tests by all clients. However, data is presented such that no individual test or client is identified.

This paper describes the results of using the Southwest Research Institute (SwRI) engine friction model to examine the effects of changing certain design parameters on the friction of a gasoline engine. The paper gives the results of an examination of the effects of changing the main and cam-shaft bearing aspect ratio on the friction of those bearings, and the effect of the tension of the piston rings, and the gas loading on them. The model predicts that the friction of the piston rings is the highest single component in the friction, except at high engine speeds, where the predicted windage was greater. Next, after the piston rings, was the piston skirt friction. The remaining components were relatively small, and in order of importance were the accessories, the cam bearing friction, cam/tappet friction, the main bearing, the crank pin, and oscillatory friction in the valve train, in that order.

This paper is the second of two that describe the effects of low-lubricity fuels on diesel injection pump performance. The first paper describes the primary failure mechanisms and wear processes in a number of failed pumps removed from both military and civilian vehicles that had been operated on Jet A-1 and diesel fuels. However, the multitude of unregulated parameters in practical operation renders quantitative comparison between different fuels and pump combinations impractical. This paper describes the degradation in pump performance and the wear processes associated with fuels of varying lubricity in the well-defined environment of a pump test stand. The test methodology concentrates on those areas previously demonstrated to be most susceptible to wear. The results indicate that pump durability is reduced by highly refined low-viscosity fuels, but may be successfully counteracted by either improved metallurgy or lubricity additives.

The U.S. Department of Defense has adopted a concept in which a single fuel will be used on the battlefield; diesel fuel will be replaced by JP-8/JP-5/Jet A-1 in compression ignition engines, thereby decreasing the fuel logistics burden. JP-8 fuel has successfully undergone extensive testing in both the laboratory and in field trials. However, increased failure rates for fuel-lubricated rotary injection pump components operating on Jet A-1 aviation turbine fuel were reported during Operation Desert Shield. This paper is the first of two and describes the disassembly and failure analysis of twelve rotary fuel injection pumps that operated on Jet A-1. Also disassembled as a baseline for comparison were three additional pumps from civilian vehicles that had operated on commercial diesel. Each of the pumps had a unique service history, making quantitative comparison difficult.

Active automotive suspension systems have been under development for a number of years with recent introductions of various versions. A suspension system can be considered “active” when an outside power source is used to alter its characteristics, and these systems can be placed into one of three (3) different categories: semi-active damping, fully active, and low frequency active. A regenerative pump concept can minimize the power requirement for the low frequency active system. It utilizes four (4) independent variable displacement pump/motor combinations on a common shaft to actuate each individual suspension unit. This paper overviews the system configuration, describes the power and energy-saving features of the system, and discusses possible pump configurations and control strategies.

Changing fuel quality, increasingly stringent exhaust emission standards, demands for higher efficiency, and the trend towards higher specific output, all contribute to the need for a better understanding of the ignition process in diesel engines. In addition to the impact on the combustion process and the resulting performance and emissions, the ignition process controls the startability of the engine, which, in turn, governs the required compressions ratio and several of the other engine design parameters. The importance of the ignition process is reflected in the fact that the only combustion property that is specified for diesel fuel is the ignition delay time as indicated by the cetane number. The objective of the work described in this paper was to determine the relationship between the ignition process as it occurs in an actual engine, to ignition in a constant volume combustion bomb.

An untreated heavy distillate fraction from a mixture of Geokinetics and Occidental shale oils was hydrogenated at three levels of severity. The three products showed good ignition quality and met most of the current specifications for No. 2-D diesel fuel. Nitrogen contents ranged from 250 to 1890 parts per million. Good oxidation stability was obtained in the product with lowest nitrogen content. Stability of the other two products was marginal but would be improved by use of an antioxidant additive. The test fuels will be used in engine and combustion studies.

This paper describes a distributed digital process control computer designed for large industrial processing plants that has been applied successfully to laboratory engine testing. Over the past two years several complete systems have been installed and adapted to control engines from 75 kW to over 1800 kW with various dynamometer/generator absorption devices. Control problems encountered, and solutions we have found, are discussed along with the wide range of capabilities this type of system can provide. A short comparison is made between distributed digital control systems and mini-computers, listing advantages and disadvantages of both.

Modifying the standard Sequence V-D test for alcohol fuels requires material changes in the fuel handling system addition of a fine mesh fuel filter and the provision for easy fuel drainage. Besides rejetting the carburetors the initial ring gaps of the 2.3L engine are reduced to maintain the blow by level of the standard test. Large oil consumption necessitates a modified oil leveling procedure. Precise measurements of the rings bores and valve-train components are essential to the evaluation of oil performance. Wear of a 2.3L engine using alcohols is larger than using gasoline. Special oils can be formulated to mitigate the wear problem. To test the 1.6L engine with the Sequence V-D procedure requires extensive modification to the production carburetor and some plumbing changes of the standard test stand. Load and initial oil charge are scaled to reflect the smaller engine requirements. Wear of the 1.6L engine is less severe than the 2.3L.

This paper describes the development of a CVS compatible sampling system for automotive sulfate emissions. The design resulted from a consensus of ideas from EPA and industry. The system can be used with either a positive displacement pump or critical flow venturi CVS. A mist generator was developed to quantitatively inject sulfuric acid into the tunnel. While sulfate losses were acceptable using the mist generator, with actual automotive exhaust sulfate losses were much higher. The reasons for these losses were investigated. Sulfate losses in the tubing between the car and sulfate tunnel were also investigated.

A new approach to reclaiming the spoil areas produced by area-type mining operations has been developed. This system uses a machine known as a winch-dozer, consisting of a pair of large back-to-back buckets which are drawn by cable across spoil piles, moving back and forth between a “tailblock” anchor and a “drawworks” winch unit developed as an attachment to a large crawler tractor. The system is expected to reduce the cost of reclamation leveling by 40-50%. The system permits more effective power utilization due to the blade system's light weight, induces caving of spoil banks, and permits moving spoil in both directions of blade travel.

The principles of the magnetic-perturbation method of flaw detection and the Barkhausen noise residual stress measurement method are briefly reviewed. It is suggested that they provide very powerful tools for assuring improved ball bearing performance. The methods are applied for the evaluation of ball bearing races. Typical experimental results are presented along with metallurgical sectioning correlation.

This paper discusses the techniques and diagnostic significance of atomic absorption, atomic emission, and infrared spectrometric analysis of crankcase lubricants, with the use of supplementary data where pertinent. The parameters affecting used oil analytical data are discussed in terms of examples from Army general purpose vehicle test engines. Wear metals in used gear oils are also discussed and examples are given. Analytical methods and their applications are fully described, and the equipment and procedures for infrared spectroscopy and gas chromatography techniques are outlined.

A technique for evaluating high temperature oxidation and corrosion tendencies of automotive crankcase lubricants is described. The technique utilizes a versatile bench apparatus which, with a minimum of modification, can be used for either evaluating thermal oxidation stability of gear lubricants or oxidation-corrosion tendencies of automotive crankcase lubricants. The apparatus is relatively compact and requires a minimal lubricant sample. Design of the apparatus permits close control of all operating parameters and provides satisfactory test data repeatability. Retainable copper-lead test bearings are used as the indicator in predicting a pass or fail of fully formulated crankcase lubricants as in the case of the CRC L-38-559 (Federal Test Method 3405) technique. Engine and bench test data are compared to illustrate the capabilities of this new bench technique.

A unique system has been devised to measure and telemeter critical temperatures of reciprocating engine components. A prototype has been used to measure the piston pin bearing temperature in a full-scale EMD 2-567D diesel engine.