O-Ring - 6.​​8X1.​​9 - Arai

removed cam cover, scraped off silicone, installed O ring , reassembled

1. Took off broken blades, blade holder and drive belt pulley. This required a two jaw puller due to bend in shaft.
2. Open up crankcase. Many steps involved. Followed youtube videos. Detailed videos exist.
3. Take out piston. Found lots of black soot on piston, crankcase and valve seats. Apparently due to mistiming from running engine with bent crankshaft since this is a pretty new engine always running smooth before accident.
4. Use carburetor cleaner and lots of work to clean piston and case. Put in new valves and use grinding compound to clean valve seats and "break in" valves.
5. Install new crankshaft (also from ereplacement) and all new parts related to timing. The old ones looked fine but did not want to have to open up again in case there was some damage not visible.
6. Assemble everything. Again lots of steps. Take pictures when disassembling, label parts and use youtube videos. A mechanic friend lent me a puller and a torque wrench.
7. New blade holder and blades.
8. Pull starter cord. Starts right off. Runs very smooth. Cuts very well. Success but it is a major project for amateurs. I am retired thus have the time and love this Honda lawnmower. Kind of expensive because of all the new parts but still cheaper than a new Honda and I have only had it a couple of years. Now it's practically new.

1) Removed plastic covers and pull starter
2) Removed valve cover bolts
3) Pried valve cover off, which was stuck on with sealant from the factory.
3a) Spent the most time cleaning off the old sealant, which was stuck to cylinder head and cover surfaces.
4) Removed old o-ring
5) Slipped new o-ring into place
6) Re-attached valve cover, following Permatex directions to seal valve cover
7) Re-attach plastic and pull starter
8) Start engine. No leaks