17 SPARK PLUG DEFECTS AND TESTS. jar is sealed by a pinch cock on the rubber hose between the jar and the aspirator. When the pressure is applied, as the air leaks through the plug, the oil level in the bell jar gradually falls, and the time required for the level to travel between any two… … Figure 1. time interval and the calibration of the jar. A leakage greater than 0.2 cubic centimeter (0.01 cubic inch) per second at a pressure of 15 kilograms per square centimeter (225 pounds per square inch) and at a temperature of 150° C. (302° F.) should be considered excessive for aviation…
NASA Technical Reports Server (NTRS)
Internet Archive · NASA Technical Reports · Public domain (US government work). Free to use for anything.
