Rebuilding a Polaris snowmobile engine involves removing the engine block and replacing the interior parts. The block may need to be cleaned and have its cylinder walls resurfaced. The process requires planning and some prior knowledge of how the machine should be taken apart and rebuilt.
To remove the engine block, disconnect the system pieces that are attached to the engine. This includes the clutch assembly, fuel lines, injectors, electrical wiring and coolant hoses. Hoses should be clamped and secured away from the engine block. String, plastic ties or even tape can be used. It also helps to label hoses and wires to ensure proper reconnection later. Having containers for spilled oil, fuel or coolant is helpful.
The next step is to remove the engine block, carefully keeping track of the removed bolts. Once the block is examined and the cylinder wall resurfaced or replaced as needed, install the remaining components of the rebuild kit. These include the pistons, O-rings, wrist pins, bearings, gaskets and clips. Lubricate and tighten all bolts to the required specifications, as this is critical once the kit components are in place. Proceed slowly and double check all piston parts to make sure they are secure.
Reinstall the block and the cylinder head to torque specifications using a standard torque wrench. Small engine parts suppliers, such as MFGSupply.com, sell service manuals that contain torque specifications for all components. Torques vary depending on the type of bolt and part. With the engine reinstalled, reconnect all external components.