The test for determination of exhaust gas cooling efficiency described in § 7.102 may be done simultaneously with this test.
(a) Test procedures.
(1) Prepare to test the diesel power package as follows:
(i) Perform a detailed check of parts against the drawings and specifications submitted to MSHA under compliance with § 7.97 to determine that the parts and drawings agree.
(ii) Fill the coolant system with a mixture of equal parts of antifreeze and water, following the procedures specified in the application, § 7.97(a)(3).
(iii) If a wet exhaust conditioner is used to cool the exhaust gas, fill the exhaust conditioner to the high or normal operating water level and have a reserve water supply available, if applicable.
(2) Tests shall be conducted as follows:
(i) The engine shall be set to the rated horsepower specified in § 7.97(a)(2).
(ii) Install sufficient temperature measuring devices to determine the location of the highest coolant temperature. The temperature measuring devices shall be accurate to ±4 °F (±2 °C).
(iii) Operate the engine at rated horsepower and with 0.5 ±0.1 percent, by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system, and other components reach their respective equilibrium temperatures. The liquid fuel temperature into the engine shall be maintained at 100 °F (38 °C) ±10 °F (6 °C) and the intake air temperature shall be maintained at 70 °F (21 °C) ±5 °F (3 °C).
(iv) Increase the coolant system temperatures until the highest coolant temperature is 205 °F to 212 °F (96 °C to 100 °C), or to the maximum temperature specified by the applicant, if lower.
(v) After all coolant system temperatures stabilize, operate the engine for 1 hour.
(vi) The ambient temperature shall be between 50 °F (10 °C) and 104 °F (40 °C) throughout the tests.
(b) Acceptable performance. The surface temperature of any external surface of the diesel power package shall not exceed 302 °F (150 °C) during the test.