ASTM D7156 Standard Test Method for Evaluation of Diesel Engine Oils in the T-11 Exhaust Gas Recirculation Diesel Engine
10. Inspection of Engine, Fuel, and Oil
10.1 Oil Inspection:
10.1.1 Analyze each oil sample for viscosity at 100 °C in accordance with Test Method D5967, Annex A3. Determine viscosity increase using the 90-pass DIN shear viscosity, see 10.1.5, as the minimum viscosity. To maintain accuracy and precision conduct all viscosity measurements at a TMC-calibrated laboratory.
10.1.2 Analyze each oil sample for soot content in accordance with Test Method D5967, Annex A4. To maintain accuracy and precision conduct all soot measurements at a TMC-calibrated laboratory. Report soot to two decimals.
10.1.3 Every 24 h, starting with the 12 h oil sample and including new and EOT samples, determine base number in accordance with Test Method D4739; determine acid number in accordance with Test Method D664; determine oxidation using integrated IR.
10.1.4 Every 24 h, starting with the 24 h oil sample and including new and EOT samples, determine iron, lead, copper, chromium, aluminum, silicon, tin, and sodium levels in accordance with Test Method D5185.
10.1.5 For the new oil sample only, determine the 30-pass DIN shear viscosity in accordance with Test Method D6278 or D7109. Also for the new oil sample, determine the 90-pass DIN shear viscosity in accordance with Test Method D7109.
10.1.6 For the 180 h and EOT oil samples, determine MRV viscosity at −20 °C in accordance with Test Method D6896. As part of the MRV measurement procedure, be sure to prepare the sample in accordance with A4.3, Annex A4 of Test Method D5967. The maximum reported result is 400 Pa·s, and use this value if the results are too viscous to measure.
10.1.7 For the 96 h, 192 h, and EOT oil samples, determine fuel dilution in accordance with Test Method D3524.
10.1.8 Conduct all oil analyses as soon as possible after sampling.
10.2 Fuel Inspections - Use fuel purchase inspection records to ensure conformance to the specifications listed in Table 1 for the last batch of fuel used during the test. In addition, perform the following inspections on new (0 h) and EOT (252 h) fuel samples: API Gravity at 15.6 °C, Test Method D287 or D4052 Total Sulfur, mass percent, Test Method D5453 (Test Method D2622 or D4294 can be substituted). Use one 1 L sample for inspections.
10.3 Oil Consumption Calculation:
10.3.1 Using the oil mass measurements taken every 6 min, see 9.6, determine the oil consumption, in grams per hour, by performing linear regression on the data starting from 25 h and ending at 252 h or when the auxiliary oil sump runs dry. The oil consumption is the slope of the regression line.
10.3.1.1 Following any shutdowns, exclude 1 h of oil mass data from the regression to account for the stabilizing of the oil scale.
10.3.1.2 The auxiliary oil sump is considered to have run dry when the oil mass curve shows a significant flattening which indicates that the oil mass is no longer decreasing.
10.3.1.3 Report the oil consumption for the test on the appropriate form. The operational validity requirement for oil consumption is shown in 11.7.1.
