SH/T 0709-2001 Water-cooled two-stroke gasoline engine oil detergency and general performance evaluation method (Mercury 15HP method)

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Card type: Test method

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

• Standard number: SH/T 0709-2001
• Chinese full name: Water-cooled two-stroke gasoline engine oil detergency and general performance evaluation method (Mercury 15HP method)
• English name: Standard test method for evaluating detergency and general performance of water-cooled two-stroke gasoline engine oil (Mercury 15HP)
• Replacement relationship: not provided in the available source (the foreword does not mention a replaced standard)
• Adoption status: equivalent adoption of the United States Outboard Marine Manufacturers Association NMMA "MERCURY 15HP test procedure (TC-W3)" (foreword)
• Publication/implementation: published on 2001-11-23, implemented on 2002-01-01; issued by the State Economic and Trade Commission
• Responsible organization: Sinopec Research Institute of Petroleum Processing
• Drafting organization: Research Institute of Sinopec Maoming Branch
• Drafters: Liang Qirui, Feng Xinping, Lin Yuesheng, Xu Shaojiong, Tang Tao, Zhou Weizheng

2. Scope of application and non-application

• Scope (Chapter 1): This standard specifies the test method for evaluating the detergency and general performance of water-cooled two-stroke gasoline engine oils (Mercury 15HP).
• Applicable: evaluation of the detergency and general performance of water-cooled two-stroke gasoline engine oils used in water-cooled two-stroke gasoline engines such as outboard motors.
• Not applicable: not provided in the available source.

3. Method principle

(Chapter 4 Method summary) A modified MERCURY 15EL or ML type outboard motor is placed in a test water tank. After the outboard motor is run in, the cylinder compression pressure is measured, then the engine is operated at idle speed 5min and at full throttle 55min for test cycle operation. During the engine cycle operation, every 10h of operation, the engine is stopped for 1h, and the cylinder compression pressure is checked; the test is run for a total of 100h. After the test, the detergency performance and lubricating performance of the oil are evaluated by assessing items such as piston ring sticking, piston deposits, piston ring surface scuffing, piston wear, piston pin needle bearing adhesion, and cylinder compression pressure drop.

4. Reagents and materials (purity / preparation)

• 6.1 Reference oils: NMMA 93738 oil is the low reference oil, and NMMA 71591 oil is the high reference oil. Each test requires 10L.
• 6.2 Sample oil: each test requires about 10L of sample oil.
• 6.3 Test fuel: use specially blended TC-W3 ring sticking fuel; physical and chemical indicators are given in Appendix C Table C1. Each engine test requires 900L.
• 6.4 Engine coolant: treat the engine cooling water to remove inorganic substances, prevent scaling and corrosion. Excessive cooling system deposits can affect the cooling effect.
• 6.5 Gearbox lubricating oil: use GL-5 gear oil, about 200mL is required each time.
• 6.6 Engine component lubricant: use NMMA 71591 reference oil to lubricate parts when assembling the engine.
• Mixed fuel preparation (7.2): mix the TC-W3 ring sticking fuel with reference oil or sample oil at a mixing ratio of 50:1( by volume), prepare about 15L for run-in; prepare about 900L for the formal test at a mixing ratio of 100:1( by volume).
• Appendix C Table C1 TC-W3 ring sticking fuel physical and chemical indicators (item | specification indicator | test method):
  • Distillation range 10% evaporation temperature, ℃: 56~70 | GB/T 6536
  • 50% evaporation temperature, ℃: 116~126 | GB/T 6536
  • 90% evaporation temperature, ℃: 180~190 | GB/T 6536
  • Dry point, ℃: 210~238 | GB/T 6536
  • Residue, %(V/V): ≤2 | GB/T 6536
  • Vapor pressure, kPa: report | GB/T 8017
  • Sulfur content, mg/kg: <800 | GB/T 380
  • Nitrogen content, mg/kg: report | SH/T 0657
  • Lead content, g/L: <0.013 | GB/T 8020
  • Gum, mg/100mL: report | GB/T 8019
  • Octane number (research method): 92~94 | GB/T 5487
  • Antiknock index: ≥87 | GB/T 5487
  • Structural composition aromatics, %(V/V): 36~43 | GB/T 11132
  • Olefins, %(V/V): 17~23 | GB/T 11132
  • Saturated hydrocarbons, %(V/V): report | GB/T 11132
  • Copper strip corrosion (50℃,3h), grade: ≤1a | GB/T 5096
  • Induction period, min: ≥3×10 (requires confirmation against the source standard (source-text extraction), the original text is ">3 hard 10") | GB/T 8018

5. Instruments and equipment

• 5.1 Test engine: MERCURY 15EL or ML type outboard motor, main technical parameters are given in Appendix A.
• 5.2 Engine modification:
  • 5.2.1 Cooling system modification (remove the water pump, remove parts such as the E type ring, plug the idle exhaust port and shaft outlet hole, drill a φ25mm hole in the side of the midsection as the cooling water inlet, install a cooling liquid outlet connector with an inner diameter of φ10mm at the exhaust side cover plate and thermostat, etc.). The powerhead cooling water is supplied by a water pump with a rated pressure of about 200kPa and a flow rate of about 250L/min, and the water temperature is adjusted through a heat exchanger.
  • 5.2.2 Fuel supply system modification: the original oil tank is used as the fuel tank for the run-in stage, and a separate fuel tank for the formal test is fabricated; the installation height shall be such that the fuel pressure at the engine inlet does not exceed 35kPa when the engine is stopped.
  • 5.2.3 Power absorption device modification: modify the propeller so that the speed at full throttle is 5500r/min±200r/min.
  • 5.2.4 Remove the throttle and steering control handle and throttle control cable, and use an automatic throttle control mechanism instead.
  • 5.2.5 Spark plug gasket modification: copper gasket thickness 1.8mm–2.2mm, outer diameter 20.8mm–22mm, inner diameter 14.3mm~14.6mm, drill two holes on the outer circumferential surface about 5mm apart with a diameter of 1mm, and silver-braze the temperature measuring thermocouple; bore out the recessed part of the spark plug seat of the cylinder head to a hole diameter of 28.5mm.
  • 5.2.6 Install an engine speed sensor probe on the outer circumference of the flywheel gear, with the probe 3mm~5mm away from the gear outer circumference.
  • 5.2.7 Carburetor modification: drill a φ25mm hole in the center of the bottom cover of the float chamber to install an adjustable main nozzle (part number C-71-29-33-20); after adjusting the flow rate, tighten the sealing nut to 7N·m.
• 5.3 Test water tank: an outboard motor test water tank, with exhaust extraction equipment installed above, capable of installing an exhaust pipe, and a wave buffer installed in the tank; a capacity greater than 7000L is recommended.
• 5.4 Instruments and meters:
  • 5.4.1 Measurement and control system: a recorder capable of continuous signal scanning and recording, with a maximum interval of less than 2s and an accuracy of ±1℃, with fault alarm function.
  • 5.4.2 Thermometers: coolant inlet and outlet temperature 0℃~200℃, intake air temperature 0℃~200℃, ambient temperature 0℃~100℃, spark plug gasket temperature 0℃~400℃, all with an accuracy of ±1℃.
  • 5.4.3 Tachometer: accurate to ±25r/min.
  • 5.4.4 Fuel flow meter: accuracy ±0.09kg/h at a flow rate of about 5kg/h; a mass flow meter is recommended.
  • 5.4.5 Timing light: a timing light for high-energy ignition systems with speed measurement and advance angle measurement.
  • 5.4.6 Barometer: measuring range 31kPa~110kPa, accuracy ±0.1kPa.
  • 5.4.7 Hygrometer: ordinary hygrometer.
• 5.5 Measurement point locations: the inlet water temperature thermocouple is 500mm from the midsection connector; the outlet water temperature thermocouple is 500mm from the cylinder head and 500mm from the exhaust side cover plate connector; the intake air temperature thermocouple is 25mm from the carburetor and located at the center of the carburetor pipe; the speed sensor probe is installed according to Figure 6; the spark plug gasket is used for temperature measurement; a sound-absorbing box may be used but must not interfere with the intake air flow.

6. Recommended operating conditions

• Table 1 Run-in operating conditions (speed r/min | time min | measures and status):
  • 700~900 | 45 | At the beginning, set the idle speed, mixture ratio and idle ignition timing for 5min
  • 5300–5700 | 1/30–1/20 | Full throttle
  • 2500~3000 | 5 | Partial throttle
  • 700–900 | 2–3 | Verify idle speed and ignition timing
  • 5300–5700 | 2–3 | Set full-throttle ignition timing
  • 3500~3800 | 15 | Partial throttle
  • 5300~5700 | 100 | Full throttle (other conditions are given in Table 2)
• Table 2 Full throttle conditions (item | indicator):
  • Speed, r/min: 5500±200
  • Coolant outlet temperature, ℃: 54.4±2.2
  • Coolant inlet and outlet temperature difference, ℃: 16.7±2.2
  • Fuel flow rate, kg/h: 4.54±0.14~5.90±0.14 (Note: based on the fuel consumption during the discriminating test between high/low reference oils, the fuel consumption should be between 4.54kg/h and 5.90kg/h)
  • Ignition timing (BTDC), °: 36±1
• Table 3 Operating conditions (item | idle | full throttle):
  • Time, min: — | 55
  • Engine speed, r/min: 800±100 | 5500±200
  • Coolant outlet temperature, ℃: record | 54±2
  • Coolant temperature difference, ℃: record | 17±2
  • Coolant flow rate, L/h: record | record
  • Fuel flow rate, kg/h: preferably neutral | 4.54±0.14~5.90±0.14
  • Ignition timing (BTDC), °: record | 36±1
• Recording frequency (8.2.2): coolant inlet temperature, outlet temperature, spark plug gasket temperature, fuel flow rate, ambient temperature, coolant inlet pressure are recorded once per hour, and recorded at 5min before each idle cycle; wide-open throttle speed is recorded once before 5min and once after 5min of each idle cycle; idle speed is recorded once per idle cycle; wide-open throttle ignition timing is recorded once every 10h; atmospheric pressure is recorded once every 4h; wet-bulb and dry-bulb temperatures are recorded once every 4h.

7. Sampling and specimen preparation

• 7.1 Engine preparation:
  • 7.1.1.1 For each test, assemble the test engine using a new modified Mercury Model 15EL or ML engine powerhead (part number OHTM15-01-1).
  • 7.1.1.2 Clean the crankcase and related parts with solvent gasoline, replace damaged components, and if necessary replace the entire short block or even the entire engine.
  • 7.1.1.3 Measure the dimensions of each part of the outboard motor according to the items in Appendix D Table D1.
  • 7.1.1.4 Assemble the engine according to the outboard motor instruction manual.
  • 7.1.1.5 Replace the GL-5 gear oil in the gearbox before each test.
• 7.2 Test fuel preparation: see Section 4 blended fuel preparation.
• Each test requires about 10L (6.2) of sample oil.

8. Analysis procedure

• 8.1 Break-in:
  • 8.1.1 Install the test engine in the test water tank, use break-in test fuel, operate the engine according to the conditions in Table 1 and Table 2, and during break-in measure and adjust the engine speed at wide-open throttle, fuel flow rate, cooling temperature, and ignition timing, using the middle value of the test conditions as the control target. At the end of the break-in test, stop the engine for 1h with the engine coolant pump off.
  • 8.1.2 Compression check: during the shutdown process of 1h, when the engine spark plug gasket temperature drops to 38℃, remove the spark plug, set the carburetor throttle to wide-open, disconnect the ignition, install a cylinder pressure gauge at the first cylinder spark plug port, pull the starter rope as if starting the engine, pull continuously 5 times, observe and record the cumulative cylinder pressure after 5 pulls (typical pressure is 827.4kPa~999.7kPa). Perform the cylinder pressure check on the second cylinder as well. Reinstall the spark plug, with the coolant pump in the stopped state.
• 8.2 Test procedure:
  • Before the test oil test, the bench should be calibrated with calibration oil, and the calibration results should meet the requirements of Appendix E.
  • 8.2.1 Formal test: after completing break-in, compression check, and 1h shutdown, start the test run using 100:1 mixture fuel. Operate in a continuous cycle of idle operation for 5min per hour and wide-open throttle operation for 55min, stop for 1h after every 10h of operation, total test time 100h. Check cylinder compression pressure at each shutdown for 1h. The transition time between each idle operation and wide-open throttle state is 2s~5s, operating conditions are shown in Table 3.
  • 8.2.2 Recording of test data: record test data according to the requirements of the items in Appendix F Table F1.
  • 8.2.3 Spark plug failure: when the engine speed changes at wide-open throttle by more than the specified value ±200r/min or the spark plug temperature changes suddenly, stop the engine and check the cause. When it is determined that the spark plug is not igniting, remove and record the spark plug condition, record the hours when the failure occurred, mark and retain the spark plug. Replace with a new spark plug and continue the test.
  • 8.2.4 Compression check: stop for 1h after every 10h of operation, and at shutdown when the spark plug gasket temperature drops to 38℃, check the cylinder compression pressure, compare with the compression pressure measured at the end of break-in, and calculate the pressure drop for each cylinder. When the pressure drop of any cylinder obtained from any compression check of 10h is greater than or equal to 138kPa, terminate the test. When the pressure drop is less than 138kPa, continue the test until 100h. When engine power loss occurs and other faults occur and shutdown inspection reveals this situation, also terminate the test.

9. Qualitative and quantitative and calculation formulas

• 9.1 After the test is completed, disassemble the engine within 12h after the completion of the test compression pressure check, and complete the evaluation content within 24h. After disassembly, first perform ring sticking scoring, then photograph the piston, cylinder head, spark plug and other evaluation components or locations, and finally perform varnish scoring on the evaluation components. If scoring cannot be done immediately, store the scoring parts in a dry environment or wrap them in dry paper that prevents vapor permeation and store them in a clean, dry, sealed plastic bag. Before scoring, the piston rings must not be subjected to any external force or interference. The bag should be labeled with the corresponding oil sample name, test number, test date, etc.
• 9.2 Photographed components: photograph the piston (including pressure-bearing surface, non-pressure-bearing surface, both sides, top, inner top), cylinder head, and spark plug.
• 9.3 Deposit and scuffing scoring: perform according to the scoring method in Appendix G.
• Appendix G Scoring points:
  • G3 Piston ring sticking scoring: free ring 10 points; blunt ring 9.5 points; spot-stuck ring or tight ring 9.0 points; cold-stuck ring 9.0 points–5.0 points; hot-stuck ring 4.0 points–0 points.
    • Standard ring cold sticking merit score = 9.4−( ring cold sticking angle × 0.01333) (formula G1); applicable to cold sticking angle 30°~330°, less than 30° is 9.0 points, greater than 330° is 5.0 points.
    • Ring hot sticking merit score = 4.4−( ring hot sticking angle × 0.01333) (formula G2); hot sticking angle less than 30° is 4.0 points, greater than 330° is 0 points.
  • G4 Piston varnish scoring: determine the severity coefficient and area percentage according to the varnish color grade in the CRC No.14 scoring manual; the severity coefficient of the most severe deposit is 1.0, and the severity coefficient of black varnish and all carbon is 1.0. Scoring locations: A. piston top ring land; B. piston second ring land; C. piston skirt; D. piston inner top. Each location has a full score of 10 points.
    • Total merit score = ∑(severity coefficient × area %) (formula G3)
  • G5 Carbon deposit scoring: surface cleanliness coefficient is 10; varnish deposit severity coefficient = 9.0+ varnish severity coefficient / 10; carbon severity coefficient is determined by thickness (Table G4: thickness < 0.1mm is 9.0; 0.1mm≤ thickness < 0.2mm is 8.0; 0.2mm≤ thickness < 0.3mm is 7.0; 0.3mm≤ thickness < 0.4mm is 6.0; 0.4mm≤ thickness < 0.8mm is 5.0; 0.8mm≤ thickness < 1.6mm is 4.0; 1.6mm≤ thickness < 3.2mm is 3.0; 3.2mm≤ thickness < 6.4mm is 2.0; 6.4mm≤ thickness < 12.8mm is 1.0; thickness ≥12.8mm is 0). Scoring locations: A. piston top; B. cylinder head; C. exhaust port blockage; D. exhaust passage blockage. Exhaust port/exhaust passage blockage is scored by blockage percentage, 0% is 10 points, 100% is 0 points.
  • G6 Piston scuffing area and circumference scoring: all adhesive wear is classified as scuffing, each side is evaluated separately and considered as 100%, calculate the scuffing area percentage and scuffing circumference percentage according to Figure G2 and Figure G3.
  • G7 Ring face wear evaluation: evaluate each ring, scuffing and scratching as one item, abrasion as another item, measure the ring face wear angle and express it as a percentage (1%~100%, 100% corresponds to 360 degrees of ring circumference).
  • G8 Needle roller bearing deposit evaluation: do not disassemble the connecting rod before scoring; during scoring, push the piston pin out of the piston, pull out the connecting rod, with the piston pin needle rollers in a vertical position, leave the needle roller bearing in the piston pin boss; reinstall the piston pin and let it stand for 5min, slowly lift the connecting rod off the table surface 60mm~70mm, keep the piston pin vertical, if all needle rollers fall off within 1min then pass, otherwise fail.
  • G9 Component appearance condition evaluation: evaluate discoloration of the piston pin, connecting rod small end bearing, connecting rod small end bearing seat, crankshaft main bearing, crankshaft main journal, connecting rod big end bearing seat, connecting rod big end bearing, crank pin, using three standard color plates for rust/varnish scoring comparison, each location has a full score of 10 points; and describe the appearance condition of the listed components; record the condition of spark plug electrodes, deposits, spark plug gap, etc. (terms: general deposits, core bridging, spark plug gap bridging, spark plug electrode erosion, pre-ignition, other).

10. Precision

not provided in the available source (this standard does not list precision clauses).

11. Report

• Chapter 10: issue the test result report according to the format in Appendix H, and attach photographs of the relevant components.
• Appendix H Table H1 Water-cooled two-stroke gasoline engine oil detergency and general performance test result report (engine model: Mercury 15HP; including sample name, pass standard, submitting unit, test method, test date; scoring locations: piston ring sticking score (top ring, second ring, subtotal, average), piston varnish score (top ring land, second ring land, piston inner top, skirt, subtotal, average), carbon deposit evaluation (piston outer top, cylinder head, exhaust port blockage %, exhaust passage blockage %), spark plug failure, crankcase, conclusion, remarks; report/review).
• Appendix H Table H2 Component evaluation (including piston scuffing circumference %, piston scuffing area %, piston ring wear circumference %, needle roller bearing sticking, component appearance description, cylinder pressure after break-in, cylinder pressure after test, cylinder pressure drop, cumulative test running time, conclusion; report/review).
• Visible limit hints in Table H1: second ring score ≥8.0, piston varnish average ≥6.0, piston scuffing circumference ≤15, piston scuffing area ≤20, cylinder pressure drop ≤138 (requires confirmation against the source standard (source-text extraction), the values in Table H1/H2 are subject to the original table).

12. Referenced documents

(Chapter 2 Referenced standards)

• GB/T 380 Determination of sulfur content in petroleum products (lamp method)
• GB/T 503 Determination of gasoline octane number (motor method)
• GB 1922 Solvent naphtha
• GB/T 5096 Copper strip corrosion test method for petroleum products
• GB/T 5487 Determination of gasoline octane number (research method)
• GB/T 6536 Petroleum products — Determination of distillation
• GB/T 8017 Petroleum products — Determination of vapor pressure (Reid method)
• GB/T 8018 Gasoline — Determination of oxidation stability (induction period method)
• GB/T 8019 Motor gasoline and aviation fuels — Determination of existent gum (jet evaporation method)
• GB/T 8020 Gasoline — Determination of lead content (atomic absorption spectrometry)
• GB/T 11132 Liquid petroleum products — Determination of hydrocarbon types (fluorescent indicator adsorption method)
• GB 17930 Unleaded motor gasoline
• SH/T 0510 Gasoline engine oils — Engine test rating method
• SH/T 0647 Water-cooled two-stroke gasoline engine oils — Evaluation of preignition tendency
• SH/T 0648 Water-cooled two-stroke gasoline engine oils — Evaluation of detergency and general performance
• SH/T 0657 Liquid petroleum hydrocarbons — Determination of trace nitrogen (oxidative combustion and chemiluminescence method)
• Appendix references: CRC No.19 "Rating method and technique for appearance and wear of deposits in water-cooled or air-cooled two-stroke engines", CRC No.14 rating manual, NMMA "TC-W3 outboard engine evaluation method" (foreword)

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.

14. Quick-reference Q&A