I finally got a chance to get out to the hangar again and attacked putting the new helicoil spark plug thread insert in. I put a bunch of grease on the tap to catch any debris, and very, very carefully started the tap in the threads. It felt like it was going in correctly, with very little force required to turn the tap, but there were a lot more shavings in the grease than I expected to see when I pulled the tap out. I peered into the hole with a small mirror and a bright light, and it is clear that the tap was cross-threaded. Drat!

I’m pretty sure there is no acceptable repair scheme for this problem, or at least none that I would be comfortable flying behind. So, I need a new cylinder. I called Aero Sport Power, but found that Bart was out of the office until the end of the month. I’ll contact him when he gets back, and have him paint a new cylinder and send it out to me, along with a set of rings, gaskets, etc.

The electrical and pitot-static connectors that I need to finish off the autopilot installation arrived yesterday, so I’ll work on that while the aircraft is down.