Which step is crucial when setting the slave valve clearance?

The critical step when setting the slave valve clearance involves cycling the solenoid valve to purge oil from the engine brake. This action is essential because it ensures that the oil that may be present in the system does not interfere with the adjustment of the valve clearance. By purging the oil, you allow for accurate and consistent measurements when setting the clearance, which is crucial for optimal engine performance and proper brake function.

In certain systems, having oil in the lines can cause the valve actuation to behave unpredictably. Thus, removing excess oil prevents hydraulic locking and allows for a precise setup. This step is vital for ensuring that the valves can operate freely after the adjustments are made, leading to improved reliability and efficiency of the engine brake system.