Question 436Motor Plants - Assistant Engineer

The correct answer is B) knurling the piston skirt surface. Knurling the piston skirt surface can help extend the service life of a worn aluminum piston when no spare parts are readily available. Knurling creates a roughened surface texture that can help improve oil retention and distribution, reducing wear on the piston skirt. This is a common maintenance practice for extending the lifespan of critical engine components when replacements are not easily obtained. The other options are not as effective for extending the service life of the piston. Turning down the piston skirt (option A) would reduce the piston diameter, potentially causing clearance issues. Building up the piston skirt with liquid epoxy (option C) may not provide a durable, long-lasting solution. Increasing the dimensions of the ring land grooves (option D) would not address the wear on the piston skirt itself.