Device and method for measuring compression amount of pull rod spring of engine

The invention relates to a device for measuring the compression amount of a pull rod spring of an engine. The device comprises a limiting support, a fixing support and an electronic measuring instrument; the electronic measuring instrument comprises a measuring rod and a measuring rod shell, wherein the measuring rod is arranged in the measuring rod shell in a telescopic mode; two ends of the limiting support are respectively connected with the supporting sleeve of a pull rod and the measuring rod; and two ends of the fixing support are respectively connected with the pull rod and the measuring rod shell. The compression amount measurement process of the pull rod spring comprises the following steps of: connecting the free end of the limiting support with the support sleeve of the pull rod; connecting the free end of the fixing support with the pull rod; setting the electronic measuring instrument to zero; and carrying out the test run process of the main unit of the engine . When the pull rod spring is compr