5.1 These are accelerated engine oil tests (known as the 1K and 1N test procedures), performed in a standardized, calibrated, stationary single-cylinder diesel engine using either mass fraction 0.4 % sulfur fuel (1K test) or mass fraction 0.04 % sulfur fuel (1N test), that give a measure of (1) piston and ring groove deposit forming tendency, (2) piston, ring and liner scuffing and (3) oil consumption.

5.2 The 1K test was correlated with vehicles equipped with certain multi-cylinder direct injection engines used in heavy duty and high speed service prior to 1989, particularly with respect to aluminum piston deposits, and oil consumption, when fuel sulfur was nominally mass fraction 0.4 %. These data are given in Research Report RR:D02-1273.⁹

5.3 The 1N test has been used to predict piston deposit formation in four-stroke cycle, direct injection, diesel engines that have been calibrated to meet 1994 U.S. federal exhaust emission requirements for heavy-duty engines operated on fuel containing less than mass fraction 0.05 % sulfur. See Research Report RR:D02-1321.⁹

5.4 These test methods are used in the establishment of diesel engine oil specification requirements as cited in Specification D4485 for appropriate API Performance Category oils (API 1509).

5.5 These test methods are also used in diesel engine oil development.

1.1 These test methods cover the performance of engine oils intended for use in certain diesel engines. They are performed in a standardized high-speed, single-cylinder diesel engine by either the 1K (0.4 % mass fuel sulfur) or 1N (0.04 % mass fuel sulfur) procedure.³ The only difference in the two test methods is the fuel used. Piston and ring groove deposit-forming tendency and oil consumption are measured. Also, the piston, the rings, and the liner are examined for distress and the rings for mobility. These test methods are required to evaluate oils intended to satisfy API service categories CF-4 and CH-4 for 1K, and CG-4 for 1N of Specification D4485.

1.2 These test methods, although based on the original Caterpillar 1K/1N procedures,³ also embody TMC information letters issued before these test methods were first published. These test methods are subject to frequent change. Until the next revision of these test methods, TMC will update changes in these test methods by the issuance of information letters which shall be obtained from TMC (see Annex A15).

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3.1 Exception—Where there is no direct SI equivalent such as screw threads, national pipe threads/diameters, tubing size, or single source equipment specified. Also Brake Specific Fuel Consumption is measured in kilograms per kilowatthour.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements appear throughout the text. Being engine tests, these test methods do have definite hazards that shall be met by safe practices (see Annex A16 on Safety Precautions).

1.5 The following is the Table of Contents:

Section

Introduction

Scope

1

Referenced documents

2

Terminology

3

Summary of Test Methods

4

Significance and Use

5

Apparatus

6

General Laboratory Requirements

6.1

Test Engine

6.2

Test Engine Accessories and Parts

6.3

Reagents and Materials

7

Test Oil Sample Requirements

8

Preparation of Apparatus

9

Engine Inspection

9.1

Engine Pre-Test Lubrication System Flush

9.2

Engine Pre-Test Measurements and Inspections

9.3

Engine Assembly

9.4

Pressure Testing of Fuel System Assembly

9.5

Calibration of Engine Test Stand

10

General Requirements and Frequency of Calibration

10.1

Runs

10.2

Specified Test Parameters

10.3

Calibration Test Acceptance Criteria

10.4

Action on Rejection of Calibration Test

10.5

Test Numbering

10.6

Reference Oils

10.7

Severity Adjustments

10.8

Engine Operating Procedure

11

Engine Run-In

11.1

Cool-Down Procedure

11.2

Warm-Up Procedure

11.3

Operating Conditions and Oil Additions

11.4

Measurement of Oil Consumption

11.5

Sampling Used Oil

11.6

Shutdowns, Lost Time and Off Tolerance Conditions

11.7

Recording of Exhaust Temperature

11.8

Air-Fuel Ratio Measurement

11.9

Recording of Engine Conditions

11.10

Humidity Requirements/Calibration/Measurement

11.11

Inspections, Photographs and Measurements

12

Reference to Reporting Form

12.1

Pre-Test Measurements of Engine Parts

12.2

Post-Test Information

12.3

Oil Inspections

12.4

Report

13

General Directions

13.1

Electronic Transmission of Test Results (Optional)

13.2

Reporting Calibration Test Results

13.3

Precision and Bias

14

Keywords

15

ANNEXES

Specifications for Test Engine and Engine Build

Annex A1

Intake Air System Details

Annex A2

Exhaust System Details

Annex A3

Cooling System Details

Annex A4

Oil System Modifications and Instrument Locations

Annex A5

Other Pressure and Temperature Measurement Locations

Annex A6

Oil Consumption Linear Regression Method

Annex A7

Test Fuel Specifications

Annex A8

Lubrication System, Flush Apparatus and Procedure

Annex A9

Engine Operating Conditions

Annex A10

Procedure for Rating Piston and Liner

Annex A11

Calculation of Percent Offset and Percent Deviation

Annex A12

1K/1N Test Reporting

Annex A13

Parts List by Part Number (P/N) and Warranty

Annex A14

Role of Test Monitoring Center

Annex A15

Safety Precautions

Annex A16

APPENDIXES

Humidity Data

Appendix X1

Statistical Equations for Mean and Standard Deviation

Appendix X2

Examples of Forms for Reporting

Appendix X3

Optional Recording of Oil Pass Limits

Appendix X4