Kohler EFI Head Replacement Turned Into a Bigger Problem

In this video, I set out to replace a damaged cylinder head on my Kohler EFI mower engine and walk through the entire process from start to finish. That includes removing the engine from the mower, disconnecting components, tearing everything down, cleaning parts, and installing the new head. While inside the engine, I also found noticeable wear with excessive play between the piston and cylinder wall; no surprise considering this engine has over 4,600 hours on it. Since this is my personal mower and not a customer machine, I decided to keep moving forward and see how far we could take the repair. Just when the job was nearly finished, things took a turn. A bolt snapped off in the opposite head, creating a problem that had to be solved before final assembly. I tried multiple methods to remove it, including welding a nut onto the broken bolt and applying heat, but sometimes repairs don’t go as planned. With the engine’s age, wear, and the additional time needed to continue, I made the call to stop and order a long block instead. In the next video, we’ll transfer the necessary parts over and get this mower back together. Real-world repairs don’t always go smoothly, and this one definitely had some surprises along the way. If you enjoy honest diagnostics, engine repair, and seeing the full process—including the setbacks—be sure to like, comment, and subscribe.