PT20J

Nothing. The oil to the prop hub on these props is a closed system so no oil flows through the prop hub unlike a hydromatic prop.

Pilots seem to overreact to a wing drop at stall. It’s not a spin. Not even close. It takes a couple of full revolutions to develop a true spin. Memorize and practice the PARE recovery. Google it.

The governor has an internal pump to create the higher pressure necessary to control the prop, so as long as the engine is rotating and there is oil available to the governor, it should be able to control the prop.

The Mooney is as spin resistant as any other normal category airplane. During certification, it had to meet CAR 3 spin requirement of recovering from a one turn spin in one and a half additional turns. It generally takes two turns for a spin to become fully developed. So, if you initiate a prompt recovery control application, it will recover. This assumes you are reasonably coordinated when it breaks. If very uncoordinated - especially in a skid - most airplanes will snap over into a spin very rapidly. If you want to investigate this, do it in an aerobatic airplane with an aerobatic instructor. People seem to fear stalls in a Mooney. I suspect it is because the Mooney wing has a more abrupt stall break than trainers. Also, some tend to drop a wing at the break which is disconcerting. This is corrected with rudder, but that is a learned response and the natural tendency is to try to use the ailerons which makes matters worse. During factory flight test, the stall strips on the wings were positioned to produce a nearly wings level stall (CAR 3 actually permits up to a 15 deg roll if recovery is delayed for one second). But over time, hangar rash, repairs, small rigging errors, etc. can cause a particular airplane to drop a wing at the stall. Mooney stalls are not a problem if you stay within what was demonstrated at certification: coordinated flight, deceleration at the rate of one mph per second until either stall or the elevator is fully deflected. If you want to investigate more aggressive situations, do it in an airplane designed for spins.

The prop control has more range of movement than necessary for normal operation to allow full control of the blade angle between the high and low pitch stops. Normally, the control is fairly far advanced because we operate at an rpm that is within a few hundred rpm of redline. But, in the event of an engine failure, pulling the prop control all the way back will drive the blades to the high pitch stop greatly reducing drag and increasing the glide distance.

As long as you can make redline rpm just before liftoff and can adjust the prop to 2400-2600 rpm for cruise, then everything is fine. Most use the cruise rpm that is smoothest and will generate desired power when combined with available manifold pressure. Personally, I take off and climb at 2700 rpm and cruise at 2500 rpm unless above 10,000’ when I use 2600 rpm to get more power from the reduced manifold pressure available at full throttle.

Are you saying that the control only moves a hair width from 2700 rpm to 2500 rpm? If so that’s not correct.

I use Aeroshell 7, same as aileron guide blocks and trim screws (fore and aft).

A leak test is supposed to be performed whenever the static system is opened per 91.411.

Naw, they don’t pass through grommets and are not in the center of the fuselage. You can see the rudder and elevator push pull tubes in the video on either side of the central trim torque tube.

Trim torque tube.

I’ve always used ABS cement which is MEK, acetone, and ABS resin. It’s black and in cases where I wanted white, I just melted white Legos in MEK.

Another source. https://www.brownaircraft.com/aircraft-wind-lacing-s/264.htm Also, Bruce Jaeger used to sell it. I don’t know if the new owners still do. https://www.jaegeraviation.com

I don't know about previous models, but according to the IPC, Mooney put teflon tape on the M20Js from S/N 24-0001 through 24-0810 and heat shrink tubing thereafter. The OP's appears to have the heat shrink. On mine, the oil from the grease allowed the heat shrink to slide out of position. Cleaning the tube with solvent, moving the tubing back into place and hitting it with a heat gun tightened it up. The additional protection may not be necessary, but the grommet is nylon which is a pretty hard material rubbing on the relatively soft aluminum torque tube, so it might be a good idea.