Fellow Comanche flyers.
Some of you were kind enough to offer advice as I worked my way through an engine roughness problem that ultimately lead to an engine overhaul (the gory details can be found here: viewtopic.php?f=95&t=6465). Well, I'm happy to report that 7406P is back in the air, with about 22 hours on a very strong running rebuild. As this was my first time going through the overhaul process I thought I'd share some quick notes about what went well, what didn't go so well, and how I fared cost wise, in the hopes that it might be useful information for someone in the future.
After debating whether to send the engine to one of the big shops (e.g. Penn Yan) I elected to go with a local shop (Aerodyne @ KPVG) because:
1. I had multiple, independent, and trustworthy references to the quality of their work.
2. I could check in on the engine during the process.
3. If there were issues afterwards the engine wouldn't have to be removed & shipped to have the warranty work done.
All in all, I'm very happy so far with my selection. The engine looks beautiful on the outside, and runs strong, especially as compared to the tired engine that it replaced. As for cost, despite a very thorough dialog in advance of the work being done, they came in 2.4k above the estimate price. Nearly all of this cost was caused by finding parts that are normally reused in a rebuilt that couldn't be in my case (e.g. pushrod tubes, hydraulic units). The additional cost was certainly warranted, I just wished I'd known about the possibility of these extra parts expenses in advance for planning purposes.
Original estimate: $19.5k
Final cost: $21.9k
Next, the real debacle. Before the overhaul I'd been having some issues with the prop governor. After the metal was found in the engine the working theory was that shavings were clogging up the fine screen to the governor. However, given the length of time since it'd been last serviced, the issues I'd had, and the fact that I wanted this airplane flying perfectly when it went back in the air, I elected to send out the governor. It went to New England propeller via the engine shop, with an overhaul quote price of $800. That's when the bad news started coming in. First I was told that the flyweights were no good, then I was told they couldn't find replacement ones anywhere, then I was told there was no PMA replacement for my model governor on a PA-24-180 (the overhaul docs tell me it's a D-1-5), and then finally I was told they'd found flyweights but they were going to be $$$. Long story short, $800 quickly turned into $2100 and I was again further over project budget. To add insult to injury, just as the governor was about to be completed, Hurricane Irene shut down the prop shop for almost a week (no power) keeping me on the ground that much longer. Throw in a prop governor hose at $275 and this was definitely the kicker of the whole affair.
Original estimate: $800
Final cost: $2375
Eventually everything was wrapped up, and the engine was ready to go back on. I had this done by Lear Stevens, also at KPVG, and they did a fantastic job as well. To keep a better eye on, and more accurately operate my rather expensive new engine, I elected to invest in a JPI-EDM-730 (cost: $2160) that seems to be worth every penny thus far. I've heard many a story of an EDM saving cylinders over the life of the engine (and thus paying for itself), and hope for that to be my case as well. The installation cost of the EDM went up a bit when we elected to take out the ADF & head to stick it in, but their price was still very fair for removing & installing the engine, installing the EDM, working through the initial engine break in, and fixing the small handful of squaks that came out in the first couple of hours.
Final cost: $2400
Start to finish, the Comanche was grounded for about 2 months, and the final project cost was $28835 (I bought the plane for $29.5k), but now she's back flying great, and hopefully will be for many hours to come. Hopefully this tale will be useful in the future to someone, either as an endorsement for Aerodyne/Lear Stevens in southeast VA, or as a tale of caution regarding prop governors and overall project cost.