Install Piston, Bearing, and Cylinder
At 15:40 in
How to Rebuild a Chainsaw Engine
What happens here
First, carefully clean the gasket surface on the engine block to ensure a proper seal with the new head gasket. Then, insert the new needle bearing into the connecting rod. Lubricate both the needle bearing and the wrist pin thoroughly with Lucas Assembly Lube. The piston's rings are pre-installed, but ensure the ring gaps are aligned with the small pins on the piston. Lubricate the inside of the new cylinder with assembly lube. Carefully insert the lubricated piston into the new cylinder, ensuring the arrow on the piston points towards the exhaust port. Attach the piston to the connecting rod using the wrist pin, securing it with the retainer clips on both sides. This is a critical step that requires precision and careful handling of small, spring-loaded clips. Consider using needle-nose pliers for easier handling of the retainer clips. Finally, apply a liberal amount of assembly lube to the inside of the new cylinder wall before attaching it to the engine block.
Goal: Properly install the new piston, bearings, and cylinder onto the engine block.
Tools and materials
- Cloth / Rag — Cleaning gasket surfaces
- Flathead Screwdriver Craftsman — Assisting with wrist pin installation
- Lucas Assembly Lube — Lubricating moving parts during assembly
- Needle-nose Pliers Milwaukee — Handling small retainer clips
- New Cylinder Stihl — Housing for the piston
- New Needle Bearing — Provides smooth movement for the wrist pin
- New Piston with Rings Stihl — The component that moves within the cylinder
- New Retainer Clips Stihl — Securing the wrist pin in the piston
- New Wrist Pin Stihl — Connects the piston to the connecting rod
- Stihl MS 500i Chainsaw — The base of the engine assembly