9.4 Set the revolution counter to the prescribed number of wheel revolutions.
9.5 Sand Flow and Sand Curtain—The rate of sand flow through the nozzles shall be between 300 g (0.66 lb)/min and 400 g (0.88 lb)/min. Do not start the wheel rotation until the proper uniform curtain of sand has been established (see Fig. 9 and Note 3).
9.5.1 The dwell time between tests shall be the time required for the temperature of the rubber wheel to return to room temperature. For Procedure B the dwell time shall be at least 30 min.
9.6 Start the wheel rotation and immediately lower the lever arm carefully to allow the specimen to contact the wheel.
9.7 When the test has run the desired number of wheel revolutions, lift the specimen away from the wheel and stop the sand flow and wheel rotation. The sand flow rate should be measured before and after a test, unless a consistent flow rate has been established.