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Is pulling the prop through a good indicator of compression? Should it be about equal difficulty for each cylinder? I recently purchased my M20C and flew it home to PA from Texas with no issues. About 3 weeks after having it cylinder 3 fouled the lower spark plug and I couldn't get it to check out during run-up. I cleaned all of the lower plugs, reinstalled them, passed run-up and flew it with no issues. The next time it wouldn't check out again... I am under the assumption that I was not aggressively leaning it and just needed to the hang of it. I decided to replace all lower sparks plugs because looking through the logs I noticed they haven't been replaced in many years (12 to be exact). I replaced them with Tempest UREM37BY's. After replacement I started it up and aggressively leaned, passed run-up, and took it for a flight with no issues. All compressions were in the 70's in March when I picked it up but it is a high time engine (1800 SMOH). The weather around here has sucked so I went to the airport just to put fuel in the tanks. I decided to pull the prop through for fun and noticed that two cylinders are fairly hard to pull though, one is slightly less and another that is not very hard. I just want to see if others think that the fouling of the cylinder 3 spark plug and having one cylinder with significantly less compression during a prop pull though could be related or if it should be checked further.

My carb heat cable seized and buckled, leaving carb heat about half on, carb temp ~40°C and climb rate miserable. My new A&P got the cable working again, but it needs to be replaced. He says McFarlane doesn't do carb heat cables any more, although I'm quite puzzled about any difference between it and a throttle or mixture cable besides length, routing and what it's hooked up to. Also need a new rod for the carb heat door to pivot around. She's flyable right now (picking her up tomorrow evening), but we have little confidence in how long it will last. I'm open to suggestions for new carb heat cable and box . . .

All the talk about cowl modifications and upgrades reminds me: my A&P/IA and I had to make some repairs to my poor doghouse. One side has a crack that's been stop-drilled but is continuing to grow. The other side had worn enough that it would not engage as the center piece that went into the slot on the spark plug cover had worn off. Forty years of remove & replace had taken its toll. The double-edge on the removable piece is worn badly but still engages. It is serviceably repaired now. We cut off the ragged edge of the non-removable center section, screwed an extension onto the back side of the spark plug cover using the original mounting holes, and made new mounting holes. Total parts increase of a half-dozen screws. Don't I remember an STC to remove the doghouse from my O-360 and replace it with new baffles? Is it still available, and where? Sure would be nice to get rid of my not-so-nice doghouse . . . Won't have to worry anymore about doing the next restoration, or what to do if it's not so easily fixable.