Andy95W

Thank goodness you’re here to tell us what we were doing wrong all these years. (PS- we do have a considerable number of current and former airline pilots here on MooneySpace.)

The ring-type probe is not very accurate compared to the actual probe that goes into the hole on the cylinder head. They generally read 40-50° lower than the other probes. For safety, I definitely would not run your #3 cylinder with the ring type probe. @47U mentioned the fire sleeve, I hadn’t heard about that and will have to try it on mine. The “intercylinder baffles” that someone mentioned isn’t a part of the doghouse, it’s the small piece of sheet metal that extends between the underside of cylinders #1 and #3 (as well as between 2 and 4 on the other side of the engine). Yours are probably there, but it would be worth a look to make sure it’s fitted properly. There is an area behind and below cylinder #3 in the vicinity of the oil pressure adjustment that can be closed up a lot using some scrap sheet metal. The doghouse is very lacking in that area. Swapping spark plugs is quick and easy and would be my first priority. As others have mentioned, about the only thing that could cause an excessively lean mixture on only one cylinder in our carbureted engines would be an induction air leak, but that would show as an extremely high EGT for #3. Checking that would be my second priority, as well as checking as much of the rest of #3’s intake manifold while you’re at it. Also checking valve lash, in case the pushrods got mixed up. I didn’t know there was a way to check the mixture distribution in a carbureted engine, could you please post that? Good luck, please keep us posted about what you find out.

That does not apply to the M20B/C/D/G, which all have the carbureted O-360.

I agree, and I also agree those pictures aren’t as conclusive as aaviationist thinks they are.

Maybe we can get @Aaviationist here to argue with Jack.

In 8 years and hundreds of times wearing my Halo headset I’ve never had this issue. I adjust the microphone once when I put it on and I don’t have to touch it again. I’ll bet the vast majority of users have experiences like mine. @Hank?

I’ll add my vote for the QT Halos. Most comfortable headsets I’ve ever worn, and I’ll also confirm the point that if the plugs aren’t comfortable, you just need to try all the different types until you find the ones that work for you. If you’re still not happy, call Phil. He’s very helpful and approachable and as mentioned above, an actual audiologist and fellow Mooney owner. He’s on MooneySpace as @pmccand123. A couple of points that haven’t been mentioned yet- the Halos are cheaper than the Clarity Aloft by a good amount, and MUCH better quality than the cheaper knock-offs hitting the market recently. Even the newest versions of the Halo with Bluetooth and a Lemo plug are about half the price of the Clarity Aloft. And you don’t have to replace batteries or risk losing your ANR. If you’re at OSH, it’s definitely worth stopping by his booth to talk with him and getting a demonstration.

You could tell by his posts he was a genuinely nice guy, even on the internet. He will be missed.

Reiff used to have an “upgrade” version that was only the cylinder bands to add to a preexisting oil sump installation. Might be worth a call to Reiff.

I’d call Don Maxwell’s shop first and describe the problem. They’ve been around long enough to have probably dealt with this before. After that, I’d call LASAR. The good news is that it’s not a huge issue. When you send it out, you may as well have them do the work required by the Dukes gear AD and restart the clock on that as well (unless it was just done very recently.)

My ‘67 M20C had an issue where the landing gear preloads were being released by the Dukes motor. It is supposed to prevent rotation of the motor shaft. Mine was releasing slightly when the gear was down, and also my gear was sagging slightly when it was retracted. It usually wasn’t enough to break contact on the up or down limit switch. It’s not really a dynamic brake but more like a clutch that holds the motor shaft stationary. I took it down to Ronnie at Dugosh (this was 30 years ago) and he disassembled the Dukes motor and installed two standard -10 washers, one on each post. The problem he said was that the springs that hold that clutch stationary get weak over time. The -10 washers are used as shims to increase the spring pressure. Ronnie was sure to explain that this is only a temporary fix, the springs need to get replaced. Also: these memories are 30 years old and two airplanes ago and before I got my A&P license.

@Phil123- try the usual places for KA-134 overhaul like Sarasota Avionics, Gulf Coast Avionics, and Bevan ( @Jake@BevanAviation). I bet a good cleaning will probably fix 90% of your issues. Those audio panels are fairly bulletproof.

I never said that, Scott. I thought it looked like a nice airplane. Just curious about some of the instruments. And if it is a 711, that explains the CHT removal. All good questions to check the logbooks for answers.

Thats a really good question. The digital Oil pressure, and temperature might be TSO’ed. Same for the fuel levels. Amperage indications don’t even have a TSO, so that is kind of a “Meh” thing. The CHT is another matter. The EDM is not certified to replace a primary CHT, so that would need a Field Approval before I signed it off. Most A&P/IAs I know would agree, but I bet it just got a logbook entry. Odder still is the vacuum gauge and the indicator light for low vacuum installed in an airplane that doesn’t have any vacuum instruments or Brittain wing leveler. I couldn’t tell if the speed brakes were vacuum driven.

@Sabremech

Hmm. My M20C has the InterAv alternator conversion. I just had it overhauled for about $800. It was still working fine when I sent it in, I had assumed it was overhauled in 2005 when the previous owner overhauled the engine, but it wasn’t. It turns out it was installed in 1995 and hadn’t been overhauled since. It had about 5500 hours on it. I did replace the voltage regulator with a PlanePower just because they are digital and far, far superior to the one that came with the original kit. My advice to anyone with a generator that wants to change to an alternator- get a used InterAv, overhauled it, and install it with a PlanePower regulator.

I went on a tower tour in DTW about 25 years ago. Similar to GeeBee, the tower supe said that if you’re in line with a bunch of other airplanes and you’re cleared for the approach, please just land and don’t worry if you had a clearance. A few years later it happened to me and we landed without a landing clearance. The tower controller told us “turn right, contact ground, cleared to land.” Thank God for common sense.

That’s a really good article, thanks for posting. I was able to save it as a PDF, it’s a lot easier to read that way. Thanks, Don!

+1. Nicely stated, Dev.

You should re-read what GeeBee wrote. He said he stopped the airplane using accumulator brake pressure. The transport category airplanes I’ve flown had hydraulic accumulators which were good for at least a few applications, and certainly enough to engage the parking brake.

@JBlueSkys- Happy Thanksgiving to you! I forgot to mention, that’s with a blanket on the nose and foam in the cowling inlets. Enjoy, good luck!

I have the same system. I preheat if it’s less than about 35°. I do one hour if it’s about 32-35, two hours if it’s 20, 3 hours if it’s 10. Reiff says 3-5 hours, or 10-12 hours for “maximum heating”. I based my times from their chart:

I forgot on my Instrument check ride in 1992. The examiner said we could probably just go over them. I shutdown, got out, and removed them. Might’ve been why I passed.

In 36 years I’ve missed three things on the list and 1 more that ISN’T on the list!