SH/T 0265-1992 Evaluation method for high-temperature oxidation and bearing corrosion of internal combustion engine oils (L-38 method)

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Card type: Test method

1. Method number / full name / English name / replacement relationship

• Standard number: SH/T 0265-92
• Chinese full name: Evaluation method for high-temperature oxidation and bearing corrosion of internal combustion engine oils (L-38 method)
• English name: not provided in the available source
• Replacement relationship: replaces SY 2630-84
• Reference adoption: United States Federal Standard FED3405.2 (L-38) "Single-cylinder evaluation method for lubricant performance"
• Approval/implementation: approved by China Petrochemical Corporation 1992-05-20, implemented on 1992-05-20
• Custodianship: technical custodianship by the Research Institute of Petroleum Processing
• Drafting: drafted under the responsibility of Dalian Petrochemical Company; main drafter Li Shijiang

2. Scope of application and non-applicability

• This standard specifies the use of a dedicated CLR single-cylinder gasoline engine to evaluate the high-temperature oxidation and bearing corrosion performance of internal combustion engine oils.
• This standard is applicable to evaluating the high-temperature oxidation resistance and corrosion resistance of internal combustion engine oils.
• Not applicable: not provided in the available source.

3. Method principle

On a dedicated CLR single-cylinder gasoline engine, using the sample as lubricant, after a trial run of 4.5h, the engine is operated for 40h under fixed operating conditions such as speed, air-fuel ratio and fuel flow rate. The sample is evaluated by measuring the weight loss of the connecting rod copper-lead bearing, the deposits formed, and the viscosity change of the sample, etc.

4. Reagents and materials (purity / preparation)

• 4.3.1 Fuel: industrial isooctane with 0.79mL of tetraethyl lead added per liter (3mL of tetraethyl lead added per gallon).
• 4.3.2 Reference oils: use FB-1 and FB-2 standard reference oils to periodically calibrate the engine to ensure consistency of test results.
• 4.3.3 Coolant: distilled water or softened water.
• 4.3.4 Solvent naphtha: meets the requirements of grade 190 in GB 1922.
• 5 Reagent: petroleum ether 60～90℃, analytical reagent.
• Preparation method: not provided in the available source.

5. Instruments and equipment

• 4.1.1 This method uses a CLR single-cylinder gasoline engine, bore 96.5mm (3.8in), stroke 95.2mm (3.75in), displacement 696.3 (42.5in³). See Appendix A for dedicated parts.
• 4.1.2 Engine parts: the piston, valve rocker arm cover, push rod cover, crankcase cover and oil pan must be tin-plated. The tin-plated surfaces shall remain smooth and intact to facilitate consistency of evaluation.
• 4.1.3 Dynamometer: a suitable power absorption device shall be selected.
• 4.1.4 Crankcase ventilation system: in order to maintain the specified crankcase pressure and extraction volume, suitable crankcase ventilation equipment, extraction control equipment and rocker arm cover air flow control equipment, etc., shall be installed. As shown in Appendix B and Appendix C.
• 4.1.5 Cooling system: in order to ensure the coolant outlet temperature and the temperature difference between inlet and outlet, a forced coolant circulation system shall be used.
• 4.1.6 Exhaust system: a wet or dry exhaust system may be used.
• 4.2.1 Measurement of load and speed: the indicating instruments used to measure engine speed and load shall be able to visually display the speed and determine the engine power.
• 4.2.2.1 Fuel flow: measure the fuel flow with a volumetric or gravimetric flow meter.
• 4.2.2.2 Measurement of crankcase blow-by: measure the crankcase blow-by with a dry gas meter with an accuracy of 28L/h (ft³/h). (requires confirmation against the source standard (source-text extraction): the accuracy unit is suspected to be of the order of 28L/h or 1ft³/h, as in the source text)
• 4.2.2.3 Measurement of air-fuel ratio: the air-fuel ratio may be measured with any one of the following instruments: a. calibrated bridge-type exhaust analyzer; b. Orsat analyzer; c. separate air and fuel flow measurement; d. gas chromatograph.
• 4.2.3 Temperature measurement: see Appendix D for the installation positions of thermocouples. The overall system accuracy shall be calibrated to ±1.1℃.
• 4.2.4 Pressure measurement: the pressure measurement positions shall be in accordance with the method requirements. See Appendix E for the specific installation positions.
• Appendix A Dedicated parts (Leibee part numbers): cylinder liner 8061; connecting rod copper-lead bearing 8276; main bearing (babbitt) 8252; camshaft thrust plate (aluminum metal) 8405; crankshaft thrust plate (babbitt) 8292; carburetor (equipped with an air-fuel ratio adjustment device) 9710 or 9651; air filter (must have a maximum pressure drop of 6inH₂O passing through, do not use an oil-bath type air filter) 9771; distributor 9667-C; spark plug (premium H-8-J, H-10 or equivalent) 3129; oil filter (full-flow type) 2418; external oil heater 2430B; water pump (must be consistent with crankshaft speed) 2416 or 12535A.
• Appendix D Thermocouple installation positions: intake air temperature—at the center of the intake pipe, 38mm (1½in) above the carburetor intake throat; coolant inlet temperature—within 102mm (4in) of the cylinder liner inlet flange; coolant outlet temperature—within 102mm (4in) of the cylinder liner outlet flange; main oil gallery oil temperature—in the front main bearing passage, immersed in oil to a depth of 35mm (1⅜in); oil pan oil temperature—at the end of the oil dipstick in the oil sump, with the thermocouple length from shoulder to end being 384mm (15⅛in). Note: the main oil gallery thermocouple model is 5A-0732 or 5A02P, Leibee part number 3114 or equivalent; the oil pan thermocouple model is 502P, Leibee part number 3113 or equivalent.
• Appendix E Pressure measurement installation positions: oil pressure—on the main oil gallery; intake vacuum—in the plane of the intake manifold elbow; crankcase vacuum—at the lower part of the breather; exhaust pressure—at 102mm (4in) of the cylinder head exhaust flange.

6. Recommended operating conditions

• 7.2.3 Test conditions (must be maintained throughout the entire test):
  • Speed: 3150 r/min ± 25
  • Load: record
  • Fuel flow: 2.16±0.11 kg/h (4.75 lb/h±0.25 lb/h)
  • Air-fuel ratio: 14.0:1±0.5:1
  • Cylinder liner coolant outlet temperature: 93.3±1.1℃ (200℉±2℉)
  • Inlet-outlet coolant temperature difference: 5.6±1.1℃ (10℉±2℉)
  • Main oil gallery oil temperature: for oils with viscosity (100℃) <5.6mm²/s, 135±1.1℃ (275℉±2℉); for oils with viscosity (100℃) >5.6mm²/s, 143±1.1℃ (290℉±2℉)
  • Ignition advance angle (before top dead center): 35°±1°
  • Oil pressure: 274.4±13.7 kPa (40 lb/in²±2 lb/in²)
  • Crankcase vacuum: 497.8±124.5 Pa (2inH₂O±0.5inH₂O)
  • Exhaust back pressure: 0～3385.2 Pa (0～1inHg)
  • Crankcase extraction volume: 850±28 L/h (30ft³/h±1ft³/h)
  • Blow-by: report
  • Note 1: adjust the load on the basis of the specified air-fuel ratio to achieve the appropriate fuel flow.
  • Note 2: under normal operating conditions, the engine is usually 283L/h±56.5L/h (10ft³/h±2ft³/h).
• 7.2.4 Sample heating time: at the start of the test, after shutdown at 10h, 20h, 30h and addition of sample, the engine is operated under the speed and load conditions of the formal test, and heated according to the following specifications:
  • 15min, oil heater power 1000W
  • 10min, 1300W
  • 10min, 1600W
  • 10min, 1900W
  • 15min, 2200W (as needed)
  • When the main oil gallery temperature reaches the specified value, start timing.

7. Sampling and sample preparation

• 7.1.2 Add new sample 2.45kg (5.4 lb) to the engine crankcase.
• 7.1.6 Add new sample 1.43kg (3.15 lb) to the engine crankcase.
• 7.2.1 Add 1.43kg (3.15 lb) of new sample to the engine crankcase.
• 7.2.5 Intermediate sampling: when the test proceeds to 10, 20, 30h, sample adjustment and sampling shall be carried out.
  • 7.2.5.1 Shutdown: before shutdown, turn off the oil heater. Stop the compressed air, run at low speed 1500r/min for 10min, then shut down, and bring the piston to top dead center of the compression stroke.
  • 7.2.5.2 After the engine has stopped for 5min, drain the sample 5min from the crankcase and oil heater into a clean, pre-weighed container, weigh it, and record the drained oil amount. Take 1.22kg (2.7 lb) from it and add it back to the crankcase, keep the remaining sample for analysis, then add new sample 0.20kg (0.45 lb) to the crankcase. (requires confirmation against the source standard (source-text extraction): the make-up amount in the source text is ".20k8(0.4516)", suspected to be 0.20kg (0.45 lb))
  • 7.2.5.3 Restart the engine and heat according to 7.2.4.
• 7.2.7 End of test: shut down according to 7.2.5.1, and after the engine has stopped for 5min, drain the sample 5min from the crankcase and oil heater, weigh it, record it, and retain the analysis sample.
• 6.2.3 Cleaning of the connecting rod copper-lead bearing: before weighing, clean it in petroleum ether. Before the final bearing weight loss is obtained, do not make any marks other than the mark on the bearing back.

8. Analytical procedure

• 6 Preparatory work before the test
  • 6.1 Engine disassembly: the engine shall be completely disassembled, and all plugs on the main oil gallery and crankshaft sludge collector shall be removed. The following parts shall be replaced for each test: piston and piston ring assembly; connecting rod copper-lead bearing; all gaskets; sealing rings; oil seals and filter elements, and parts exceeding the specified clearance.
  • 6.2.1.1 Before each test, clean all parts with solvent naphtha. Special attention shall be paid to cleaning the sludge collector, crankshaft and camshaft oil passages, valve lifters, timing gear oil supply nozzles, evaluation surfaces, oil passages of the cylinder block and crankcase side cover plates, etc., and blow dry with compressed air.
  • 6.2.1.2 Cylinder head: The cylinder head must be thoroughly cleaned and inspected. The rocker arm shaft lubrication system (i.e., oil line rocker arms, rocker arm shaft, and rocker arm shaft supports), valves, valve seats, and coolant passages must also be carefully inspected.
  • 6.2.1.3 The oil pump, distributor, breather, and main oil gallery pressure relief valve are removed from the side cover plate. All oil passages of these parts must be scrubbed with a fiber brush, and the oil pump and main oil gallery pressure relief valve must also be carefully spray-washed. The crankcase breather must also be disassembled, inspected, and cleaned.
  • 6.2.1.4 Sealing of the rear main crankshaft bearing: Before each test, carefully inspect the sealing surface of the rear main bearing and the contact condition of the oil seal to avoid leakage of oil and air.
  • 6.2.2 Cleaning of the oil heater: Before each test, the oil heater housing and the internal heat-generating element must be thoroughly cleaned. The fusible alloy must be inspected, and if insufficient, it must be replenished.
  • 6.3.1 After cleaning, inspect and replace defective parts or parts with relatively large wear.
  • 6.3.2 Every 6 tests, replace the cylinder liner.
  • 6.3.3 For inspection of clearances of engine components, see Appendix F.
  • 6.4.1 Engine assembly shall be installed and fastened according to specified clearances and torques. For specific requirements, see Appendix G.
  • 6.4.2 Spark plug gap is 0.76mm (0.03in), and contact breaker point gap is 0.51mm (0.020in).
  • 6.4.3 When assembling the engine, qualified connecting rod copper-lead bearings must be used, and the bearing batch number must be noted. Before installation, each bearing shell must be marked with "upper" and "lower" on its back. Both bearing shells must be carefully cleaned and then weighed, accurate to 0.2mg.
  • 6.5.1 A new engine or an engine fitted with a new crankcase cannot directly undergo the formal test. In order to make the condition of the engine cast iron parts meet the test requirements, a "passivation" test must be carried out with FB-1 reference oil according to the formal test procedures for running-in, but test results are not taken.
  • 6.5.2 After every 11th test, a calibration test of the equipment shall be carried out with FB-2 reference oil. Every year, calibration tests of the equipment must be carried out with FB-1 and FB-2 reference oils to ensure that the tests have consistent severity. For the data ranges of test results with FB-1 and FB-2 reference oils, see Appendix H.
• 7.1 Running-in
  • 7.1.1 Replace the oil heater and connect a full-flow oil filter, using 1 new filter elements for each test.
  • 7.1.3 Carry out the initial running-in of the engine under the following conditions:
    • 1h, 1500 r/min, load 1.5kW, ignition advance angle 25°
    • 1h, 2000 r/min, load 2.9kW, ignition advance angle 25°
    • 1h, 2500 r/min, load 3.7kW, ignition advance angle 35°
    • 1h, 3150 r/min, load 3.7kW, ignition advance angle 35°
    • Maximum oil temperature in the main oil gallery 107.2℃ (225℉)
    • Maximum temperature at the water jacket outlet 93.3℃ (200℉)
  • 7.1.4 After running for 4h, stop the engine. Place the piston at top dead center of the compression stroke and immediately drain the crankcase sample 10min.
  • 7.1.5 Remove the full-flow oil filter and install the oil heater.
  • 7.1.7 Carry out the final running-in of the engine for 0.5h under the following conditions (oil heater not energized): 3150 r/min, load 3.7kW, ignition advance angle 35°.
  • 7.1.8 After the final running-in is completed, stop the engine with the piston at top dead center of the compression stroke, and immediately drain the oil from the crankcase and heater 10min.
• 7.2 Formal test
  • 7.2.2 Test 40h under the specified test conditions (see 7.2.3).
  • 7.2.6 Intermediate bearing evaluation: If necessary, after running-in and after every interval of 10h, the connecting rod copper-lead bearings may be removed, cleaned, weighed, and then reinstalled.
  • 7.2.8 Calculation of sample consumption: For each 10h test, the sample consumption is calculated as "g/h". The average sample consumption of 40h must not exceed 16.7g/h (0.037 lb/h), otherwise the test results are invalid.
  • 7.2.9.1 Record the following data every hour: engine speed r/min; engine load kW; fuel consumption kg/h (lb/h); oil pan temperature ℃ (℉); main oil gallery temperature ℃ (℉); water jacket outlet coolant temperature ℃ (℉); water jacket inlet coolant temperature ℃ (℉); oil pressure kPa (lb/in²); crankcase vacuum Pa (inH₂O); exhaust back pressure Pa (inHg); intake air temperature ℃ (℉); oil heater input power W; crankcase scavenging flow rate L/h (ft³/h); rocker cover blow-by flow rate L/h (ft³/h); intake manifold vacuum Pa (inHg).
  • 7.2.9.2 At the 1h of each 10h operating cycle, the air-fuel ratio and ignition advance angle must be reported, and adjustments may be made if necessary.
  • 7.2.9.3 All oil fill amounts and oil drain amounts must be recorded.

9. Qualitative and Quantitative Determination and Calculation Formulas

• 8.1 Determination of test bearing weight loss: After completing the test, remove the test bearings and clean and weigh them as specified in 6.2.3, accurate to 0.2mg. The difference between the weight before running-in and after the test is the total weight loss of the bearings.
• 8.2 Sample analysis: The changes in the sample during the 10, 20, 30, and 40h tests are determined by the following methods for acid value and kinematic viscosity at 40℃ and 100℃.
  • Kinematic viscosity 40℃ mm²/s: GB/T 265
  • Kinematic viscosity 100℃ mm²/s: GB/T 265
  • Acid value mgKOH/g: GB/T 264
• 8.3 Deposit evaluation: Evaluate the following locations according to the lacquer film and sludge rating methods, and report their ratings.
  • 8.3.1 Locations for lacquer film evaluation: oil pan, valve rocker cover, crankcase cover plate, valve pushrod cover, cylinder wall (below the piston ring stroke).
  • 8.3.2 Locations for sludge evaluation: oil pan, valve pushrod cover, valve rocker cover, crankcase cover plate, valve rocker arms, oil pump screen.
• 8.4 Result report: Expressed by connecting rod copper-lead bearing weight loss, sample analysis results, deposit evaluation, operating conditions, sample consumption, and engine measured results. Report the test results according to the format in Appendix I.
• Calculation formulas: not provided in the available source.

10. Precision

not provided in the available source.

11. Report

• 8.4 Result report: Expressed by connecting rod copper-lead bearing weight loss, sample analysis results, deposit evaluation, operating conditions, sample consumption, and engine measured results. Report the test results according to the format in Appendix I.
• Appendix I Internal combustion engine oil high-temperature oxidation and bearing corrosion test result report (reference item) includes:
  • Test number, fuel type, sample, test name, test time, date, bearing batch number.
  • 11 Connecting rod copper-lead bearing weight loss: 40h mg; 10h, 20h, 30h respectively record upper bearing, lower bearing, total (10, 20, 30h are arbitrarily selected).
  • 12 Engine deposit inspection: 12.1 Lacquer film deposits—piston skirt, valve rocker cover, valve pushrod cover, cylinder wall (below the piston ring stroke), oil pan, crankcase cover plate; 12.2 Sludge deposits—valve rocker arms, valve rocker cover, valve pushrod cover, oil pump screen, oil pan, crankcase cover plate.
  • 13 Sample analysis: Items include acid value mgKOH/g, viscosity mm²/s (100℃, 40℃), viscosity increase rate % (100℃, 40℃); respectively record new sample, 10h, 20h, 30h, 40h used samples.
  • 14 Test conditions: speed r/min, air-fuel ratio, fuel flow rate kg/h (lb/h), load kW, oil heater input power W, crankcase blow-by L/h (ft³/h), oil consumption g/h (lb/h); respectively record the average, minimum, and maximum of 0-10h, 10-20h, 20-30h, 30-40h, 0-40h. Temperature ℃ (℉): oil pan, main oil gallery, intake air temperature, heater temperature, coolant outlet, coolant inlet. Pressure kPa (lb/in²): oil; intake manifold vacuum Pa (inHg); exhaust back pressure Pa (inHg); crankcase vacuum Pa (inH₂O).
  • 15 Engine measurements: valve stem clearance in guide mm (in)—exhaust valve, intake valve; connecting rod bearing clearance; main bearing clearance; crankshaft journal roundness.

12. Referenced Documents

• GB/T 264 Determination of Acid Value of Petroleum Products
• GB/T 265 Determination of Kinematic Viscosity of Petroleum Products and Calculation of Dynamic Viscosity
• GB 1922 Solvent Naphtha
• Reference adoption: United States Federal Standard FED3405.2 (L-38) "Single-Cylinder Rating Method for Lubricant Performance"

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

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