This document provides instructions for removing and installing an engine from a Caterpillar 420F2 backhoe loader. It outlines 19 steps to remove the engine, which include draining fluids, disconnecting wiring harnesses, removing mounting hardware, and lifting the engine out. The 18 steps listed to install the engine describe reconnecting wiring, installing mounting hardware, refilling fluids, and reinstalling removed components. The document is a service repair manual that details the process to remove and install an engine on the specified backhoe loader model.