Properties:

A device consisting of two or more gages or indicators mounted in a single unit, and capable of determining two or more different mechanical performance characteristics of an internal combustion engine, or its component systems, while functioning under engine operating conditions, by making either a single or a multiple test in order to determine one or more engine characteristics similar to the following: cylinder compression, engine oil pressure, carburator adjustment, manifold vacuum, fuel pump pressure, and the like. It does not include permanently installed gages, or any devices designed to test electrical components or characteristics of an engine. See also tester, ignition system, engine.