PT20J

Different actuator. These gears are in the Dukes/ITT actuators. The springs are in the Plessey/Eaton actuators used in later models.

i think the incident reports get filed because of the subsequent gear up landing. I’m not sure that the reports I listed are a complete listing. I only searched the AIDS database for “no back”. Also, there is no guarantee that every incident was reported.

I did the lower inside of mine by hand with Novus, but it took a long time and mine wasn’t too bad. I would try Micro-Mesh which is a kit of several progressively finer grits of sandpaper. I used it to remove scratches on the side windows of my previous plane and it was pretty fast. I believe Mooney puts teflon tape on the edge of the glares shield which I replaced, but I found that it still scratches the windshield so I put some window trim edging on it.

I use that when I need to fill in an area. Afterwards, any small imperfections can be filled with Bondo glazing and spot putty. My glareshield was in pretty sad shape and I fixed it up with and then sprayed it with SEM texture and black color coat.

9/15/91 Lancaster, PA M20J: UNABLE TO RETRACT GEAR ON CLIMB. EXTENDED GEAR AND LANDED. GEAR ACTUATOR WAS JAMMED DUE TO CLUTCH SPRING FAILURE. FAA AIDS report number 19910915046159I 7/5/03 Oxford, CT M20R: WHILE ON FINAL APPROACH THE GEAR FAILED TO EXTEND. PILOT DIVERTED TO WATERBURY OXFORT AIRPORT IN CT, WHERE HE LANDED GEAR UP. INVESTIGATION REVEALED THAT THE LANDING GEAR ACTUATOR "NO BACK SPRING" HAD A BROKEN TAB WHICH CAUSED THE ACTUATOR TO MALFUNCTION. FAA AIDS report number 20030705013639I 10/30/03 Toms River, NJ M20S: LANDING GEAR WOULD NOT EXTEND. PILOT LANDED GEAR UP. THE AIRCRAFT WAS JACKED AND THE GEAR TESTED IN NORMAL AND EMERGENCY SYSTEMS. GEAR WOULD NOT MOVE IN EITHER POSITION. DISASSEMBLED THE LANDING GEAR ACTUATOR. FOUND THE TABS HAD BROKEN OFF THE NO BACK CLUTCH SPRING PREVENTING THE GEAR FROM MOVING IN EITHER THE NORMAL OR EMERGENCY POSITION. FAA AIDS report number 20031030030799I 6/12/22 Charleston, SC M20J. This was classified as an accident and investigated by the NTSB because of substantial damage to the structure during the gear up landing. The failed spring had been replaced nearly 5 years and 427 hours earlier. Probable cause: THE FAILURE OF THE TORSION SPRING (Note: This was a Plessey actuator. Eaton calls the part a "no back spring" but Plessey calls it a "torsion spring") INSIDE THE DRIVE CLUTCH ASSEMBLY OF THE LANDING GEAR ACTUATOR WHICH PREVENTED NORMAL AND MANUAL EXTENSION OF THE LANDING GEAR. NTSB accident report number ERA22LA319

I'm sure Rich knows this, but if you try to straighten warped interior plastic pieces with a heat gun be aware that the temperature where the plastic gets soft enough to reshape is very near the temperature where it will get so soft that it completely loses its shape and wrinkles up. Like Lee, I find that ABS cement works well with glass cloth to repair areas that need to be flexible. I usually use two layers of cloth and have done that at every screw hole to reinforce the area. If an area does not need to be as flexible and needs more strength, I glue a piece of ABS to the back.

Try this. Every manufacturer has it's own numbering system. Just check the dimensions. https://www.aircraftspruce.com/catalog/pnpages/MW-3.php

The 1980 rev of the M20 Service and Maintenance Manual that covers M20C, D, E, F lists the use of graphite in exactly the same three places as the M20J manual.

There were a couple of Plessey failures at around 1000 hours. That may be the origin of the 1000 hour requirement - I don't know for sure. Keep in mind that the 1000 hour mandatory replacement applies to both Plessey and Eaton actuators. Don Maxwell told me that he understood that the Eaton spring was rated for something like 20,000 operations.

Maybe a shot in the dark. My muffler normally has half an inch clearance to the right cowl flap inboard hinge, but hits it when the engine shakes during shutdown. The spinner has never aligned exactly with the top cowling showing about a half inch jog with the spinner pointed down a bit. We put in new mounts with the rebuilt engine and it still didn't line up. I noticed that it was worse after a flight and we found that the bracket that the bottom cowl attaches to just ahead of the nose gear was cracked. We repaired that but it didn't change anything; the cowling still rocked back a bit from air pressure in flight closing the gap between the top cowling and the cowl in front of the windshield. I replaced all the Camlocs that attach the cowling to the fuselage with Skybolt high shear fasteners and that solved the rocking back problem but it's still out of alignment about 3/8" and although the contact with the muffler on shut down is better, it still touches slightly. So, we're going to have to mess with the shims.

I think is because Whelen got an STC for the lights.

If you like the shop and the quality of work, I would just accept it and not quibble over it. Mooney owners have a bad reputation for being cheap bastards and given the decreasing number of good repair shops and mechanics, I would want to develop a good relationship with a shop you trust. A lot of things on a Mooney are difficult to access and take extra time and unless you are standing there with a stop watch you really have no reasonable basis to question their numbers except a bunch of opinions from the internet. It looks like they noticed air leakage from the #1 exhaust valve during the compression test and lapped the valve. If it were mine, I'd run it for a few hours and recheck the compression to see that it came up, but that's just because I'm an engineer and like to verify results. I'm sure it's airworthy as is or they would not have signed it off.

The only place powdered graphite is listed in the M20J service manual is for the locks. It is listed as an alternate lubricant for the starter drive and the control tube guide blocks, but in both cases it is mixed with kerosene (starter drive) or grease (guide blocks). Galvanic corrosion will only occur when water is present and the the kerosene or grease would most likely prevent any corrosion. Still, the alternative lubricants listed would be a better choice and don't require mixing.

When talking about no-back springs, it is important to distinguish between the two actuator manufacturers that Mooney used. There have been a number of documented failures of springs in GEC/Plessey actuators and I do not believe that no-back springs are available for these. The Eaton actuators (which confusingly were manufactured under several names) seem more robust. There was at least one (maybe two) documented failures many years ago causing Eaton to recall certain serial numbers which I believe is the source of the idea that there was a bad batch of springs. Probably some of these were never pulled and sent back to Eaton, but if they were going to fail, they'd certainly have done so by now. The spring is a wrap spring brake/clutch and it will wear in service. The chattering that Don Maxwell speaks of as a symptom of needing replacement is undoubtably caused by slippage of a worn spring. Outright failure is caused when the tangs on either end of the spring break jamming up the mechanism. I think this is a very, very unlikely event and I'm in no hurry to replace mine given the possibility of a maintenance-induced failure especially since there are now very few mechanics that have any significant experience working on these things. But, each owner will need to assess the risk and chose a course of action that they believe appropriate.

I just taped around them with masking tape before spraying.

I wouldn’t do that. Graphite can cause galvanic corrosion of steel and especially aluminum. I believe the Air Force prohibits its use on aircraft.

MLG trunions are sometimes easier to make take grease if you slightly retract the gear and move wheel up and down while greasing.

You could measure the diameter and grip to determine the AN or MS part number for the bolt and then a search of the IPC will show where that bolt is used.

Those switches have a fairly high failure rate - if it were me, I’d replace the whole switch.

The boost pump is listed as required equipment in the TCDS, so flying without it would be a violation of FAR 91.9. But, if you just want to ground run it, you could spray some starting fluid in the intake manifold.

An intake leak significant enough to affect cruise should result in a really rough idle. Full power fuel flow of 18+ gph at sea level seems about right. My IO-360-A3B6 flows that on takeoff. Before tearing into the engine, I'd check all the connections to the #3 CHT probe wiring and swap the CHT connections to another channel on the engine monitor. It might be an issue with the monitor rather than the probe.

Usually a relay or a microswitch. There are a bunch of past threads on this and a current one

Sorry to circle back to the original topic, but I tried putting the flaps down to 15 deg (TO in my MSE) while level at 2000' with the autopilot set to ALT and the airspeed at 105 KIAS. The result was a change in pitch angle to about 3 deg nose down and no change in airspeed.

True, I should have said just below stall.

To minimize the altitude loss in the turn you need to load the wing to just above stall. But, since you will want best glide speed coming out of the turn, I’ve found a good compromise is to fly the turn at best glide speed.