Check the performance of the centrifugal ignition timing controller (see above).
Connect a vacuum pump to the regulator vacuum connection.
Set the crankshaft speed to 2500 rpm and determine the value of the ignition timing with the centrifugal regulator in degrees relative to the zero division of the scale.
Set the vacuum values according to the schedule given in subsection «Detailed Specifications» and set the crankshaft speed to 2500 rpm.
Measure the ignition advance angle and determine the ignition advance angle provided by the vacuum regulator by subtracting the amount of ignition advance relative to the zero division of the scale from the obtained value.
If the value obtained does not correspond to that shown on the graph, check the ignition distribution sensor on the stand.