PT20J

So, my engine was rebuilt by Lycoming in Sept 2018. I emailed Lycoming and asked if my engine was subject to the AD figuring that since they built it, they should know. They responded that their records show that it left the factory with 77450 connecting rods. Well, I could have figured that out from the IPC. So, I emailed them again pointing out that the AD references specific "ship" dates for the various connecting rods and asked how I could determine what the ship date was for the rods in my engine. It's late on a Friday, so I may not get a response until next week.

I’m doing my annual now and I looked at my installation today and I cannot imagine it taking more than 2.5 hrs per servo. The wiring is in place, the brackets are in place, the cables are in place. You just need to loosen the cables, disconnect the electrical connector, remove the servo, install the new servo, connect the connector and tension the cables.

The symptoms as described do not make sense. 1. Only happens when cold 2. Motor stops before the gear is fully retracted but continues to draw current. 3. Gear CB does not trip 4. Fully retracts if gear is cycled. If it were a mechanical problem stalling the motor it should pop the breaker. When the motor stops running, it’s generally because power has been removed by a limit switch, relay or safety switch (squat or airspeed). Early M20Js have a squat switch on the left main gear. If the shock disks are good, I’d check the switch adjustment. If your airplane has a red override button next to the gear switch, you can press and hold that and if that causes the gear to retract fully it will confirm that the squat switch is the problem.

General Tool makes a ratcheting screwdriver that I use for removing the glare shield screws.

I replaced mine. Great Lakes Aero made them for Mooney. They are polycarbonate (aka Lexan), not acrylic. Polycarbonate is softer and more impact and crack resistant but I find it harder to work with than acrylic. Because it is soft, it doesn't polish out as well as acrylic, but you cannot hurt anything by trying. I trimmed mine and it was a lot of work. If I were to do it again, I'd send the originals to Great Lakes and have them trim and drill them. If you drill them yourself, a step drill works best. I deleted the trim piece on mine as the later models. If you do this, drill the holes oversize and use countersink washers. No need to countersink the plastic.

Agree. For me, it’s the safety issue since I’m around the prop putting the plane away.

I’ve tried opening the mixture after shutdown to bleed off the pressure and then closing it again. But the problem is the residual heat in the engine compartment will cause the pressure to increase again. If I check it again ten minutes later, the gauge will be pegged again. I don't know how high it gets. The factory gauge pegged at 30 psi. The Garmin G3X EIS will read to 75 psi and it will peg that. I haven’t seen that it hurts anything, and I don’t like leaving fuel in the hot cylinders after shutdown, so I just ignore it. With the mixture in ICO, the pressure can’t reach the servo internals. Someone posted that theirs apparently forced the mixture control shaft out against the internal spring and it became disconnected from the mixture plate, but I’ve never had that happen.

Not a bad idea and certainly worth a try. Use contact cleaner. WD-40 or other lubes will gum them up.

I would be truly amazed if you could get a OPP for $3K.

All the price increase may not be solely due to LASAR's markup or EATON price. If you were the CEO of Mooney and were strapped for cash and held the keys to the kingdom, would you turn the keys over to someone for free? I wouldn't. For all we know, it's a three way split: $1000 for EATON, $1000 for Mooney, $1000 for LASAR. We don't know. And frankly, it's none of our business. Privately held companies do not generally share a lot details of their cost structure with their customers. But, if you need/want a spring, this is the only game in town.

The last one is a mystery. Someone isn't telling the truth. But the investigator (whoever that was) could not find anything wrong with the actuator. The second and third reports involved a M20R and M20S, respectively. Those likely had Plessey actuators.

That looks like a standard part. If you can take the unit apart and get the part number, you may be able to find them at one of the electronic component suppliers such as Digi-Key or Newark.

See if you can get them to flash ... --- ...

The emergency gear extension system only protects against electrical failures. If the spring breaks, it jams up the gear train and the emergency system won’t work either, no matter where you put a zip tie. There are gear ups almost weekly caused by pilots failing to put the gear down. Happens with the manual gear, too. By comparison, there have only been a handful of spring failures over decades. Some of us are stressing out over a very small risk.

The dipstick should have a part number on it somewhere. You could check it against the IPC for your engine to confirm that it is correct.

If you are worried about it you could try this https://www.phillips66lubricants.com/product/aviation-anti-rust-oil/

I believe that the no-back spring is technically a wrap spring brake/clutch. Here's a video that explains the idea. Note, however that the Mooney actuator design is different because it has no friction disks and only needs to brake in the gear down direction to prevent the wheels from descending since there are no up locks. It doesn't back drive when the wheels are down due to the overcenter locking of the gear components.

Don, good move to rid yourself of the Plessey. I believe all the failures resulting in gear ups (except for perhaps one due to a bad batch of springs years ago from Eaton) are in Plessey's and they've been out of production for years and no parts are available. Most recent was a M20J with a Plessey actuator that geared up June 12, 2022 (NTSB Accident Number ERA22LA319) that had a torsion spring break at the tang (Plessey called them torsion springs; Eaton called them no-back springs; Mooney seems to have generalized on the Eaton nomenclature). Interestingly, the torsion spring had been replaced 427 hours before the accident. (No idea where someone found the unobtainium part). I would not be too concerned about an Eaton. Don Maxwell told me that the Eaton actuator is supposed to be designed for 20,000 operations. I don't know if that's correct or not, but it seems reasonable. Tom also replaced the spring in my 1978 M20J many moons ago. I don't have any records for that airplane any longer, but I don't recall it being particularly expensive. Skip

LASAR charges around $10K for an overhauled exchange actuator. You can bet that the springs aren’t costing them $3K. The other high wear part is the emergency extension clutch. I wonder where they get those. Also, there are reports of some Eaton jackscrews chipping. Same question. Before I paid $10K for an overhauled actuator, I’d want to know exactly “overhauled” entails.

You are way overthinking this

The Lycoming letter posted by @PeytonM references multiple supplier issues. I’ve noticed that a lot of businesses have not recovered from the disruption caused by the COVID-19 pandemic. I now stock up on a lot of personal items because I cannot depend on stores having them when I need them. A lot of healthcare professionals have retired leading to a shortage. My dentist has been trying to hire hygienists for months. It takes months to schedule an appointment with my primary care physician.

I think Mooney had several iterations. My 1978 J had a glare shield with no center hump and a metal plate around the center post. The metal plate was held down with three flat head machine screws. I don’t recall what they screwed in to, but there must have been nutplates. There may have also been a couple of sheet metal screws. My 1994 J glare shield with the center hump has two trim screws which are #6 sheet metal screws.

It probably depends on what the problem is. I've talked to people that freed up a stuck compression ring and raised the compression with the technique. I don't personally know of anyone that has used it for high oil consumption, but @kortopateswould be the expert on this. At least is is simple and noninvasive.

For sure Eaton has plenty of insurance. They make a bunch of similar actuators for various aircraft applications. We aren't privy to Mooney's arrangement with Eaton, Mooney's deal with LASAR, or LASAR's deal with Eaton. Maybe everyone is feeding at this trough. Who knows?