The RON/MON octane engine shall be warmed-up for 40-60 min. for the purpose of stabilizing the octane engine critical variables and operating conditions, so as to obtain accurate and stable test results, before performing a fuel sample octane rating.
During RON/MON octane engine warm-up, periodically monitor the operating conditions. Important conditions that may need adjustment are as follows:
■ After four or five minutes of operation, adjust the cylinder height, adjusting the C.R. until a light knock sound is heard. As the octane engine continues to warm-up, it is normal for this knock level to increase.
■ With the engine knocking, adjust the fuel level and set it to achieve audible maximum knock intensity.
■ Check engine crankcase oil level that should be near middle of sight glass with the engine warmed up.
■ Observe intake air temperature and, if applicable, the mixture temperature, both of which should equilibrate at the values specified for the appropriate standard test method.
■ Check that cooling water discharge is occurring and that the discharged water temperature is warm but not steaming.