N201MKTurbo

It is a cheap and easy mod. If you have sheet metal skills, it is an afternoon project. The hardest part is removing the lower cowl. Just remember measure twice and cut once.

Mine was leaking oil and it was getting on the vacuum pump. I replaced the seal twice and it wouldn’t stop leaking. I chucked the shaft in a lathe and polished the surface the seal rides on. It hasn’t leaked since.

The scavenger pump is a positive displacement pump. It slurps up the oil like the last bits of milkshake in the bottom of the glass. It pulls air in through both the turbine and compressor sides of the shaft. The oil pump pushes the oil into the bearings and the scavenger pump slurps it up. If you idle for a long time, it may not slurp hard enough and the turbo and return lines can fill with oil. The check valves are supposed to keep it from draining back into the turbo. If it drains back into the turbo, it will seep into the turbine and compressor housings.this doesn’t hurt anything, but it will make a big cloud of oil smoke when you start up. It will burn the oil in the turbine housing and the oil in the compressor housing will get sucked into the intake and make oil smoke. Your oil consumption will also increase because on every shutdown you will lose the oil that drains into the turbo. If enough oil drains into the turbo, it will drain out the tail pipe. If you just kick up the RPMs for a few seconds before shutdown, the scavenger pump will slurp up all that oil.

The rules for certified airplanes have been in place for a long time. You must have known that when you bought your plane. It sounds like you would be happier with an experimental. A nice RV6 or something like that.

You are fine. I’m sure she won’t do it again. Our Mooneys are tough birds.

I worked at a place that had a vapor degreaser that was used to clean the flux off of circuit boards. It sprung a leak one day and I was asked to fix it. There I was laying in a 1 inch deep puddle of the stuff. It’s a wonder I’m still alive…

I would look at the check valves before I would do anything with the turbo. A brand new turbo will do that if the check valves start leaking.

I don't know the history. I think the likely scenario is that Mooney was having a lot of gear failures, had a big meeting with Dukes and they all decided to to design a set of 40:1 replacement gears. I would just assume Dukes made the replacement gears. They were the gear guys after all.

When I did my panel upgrade in 2017 before I wired anything I drew schematics for everything. It made the install much easier. I have an old copy of Altium Designer I used for the schematics. I was doing the annual on a 310 recently and I had some questions about some of the new wiring. The owner said "I think I have that". He produced a complete set of schematics for the latest avionics upgrade. They were very well done. So, a good set of schematics are not unheard of.

I imagine the demand for these gear sets is very low. Seeing that LASAR is the top repair station for these actuators, It would be interesting to ask LASAR how many sets they have on order and how many they would use a year.

That is the same as here. There are two ways to get a PMA. You can document that you are making exact copies of the approved part, which is what you described. You can also design new parts from scratch, in which case you need to submit all the design documentation that proves the parts meet the requirements. You will need a DER to review your engineering documents.

Yes, for the annual, you give it a few pumps of grease till it comes out the screw hole. This is done in the plane.

No clue. When I do the 200 hour, I take actuator out of the plane. I remove the gear cover and remove the ring gear. Then I wash out all the old grease so it is nice and clean plus I can inspect the gears. Then I replace the ring gear, pack the gearbox with the moly grease and replace the cover. Then I will give it a couple of pumps of grease through the zerk, till it comes out of the screw hole. Then I put it back in the plane.

I have wondered the same thing. Gears wear by cycles, grease dries out by time. Choose your poison.

I doubt Mooney designed the gears or owns the drawings for the gears. They probably specified the stroke, force and speed of the actuator to the actuator company (Dukes) and they designed the actuator including the gears. I’m sure Dukes has all the drawings for the actuator, including the gears. It is possible that Dukes didn’t make the gears either, they may have farmed out the gears to another shop. Who knows who that shop is. So to get new gears, Mooney will need to issue an RFQ to Dukes to find out what they want. Once the quote is issued, Mooney needs to issue a PO. Then Dukes will have to set up a project to produce the gears, which probably involves the same interaction with their gear vendor. And what if Dukes does a No Quote response? You cannot force them to make the parts. You can only negotiate at that point to find some way to convince them do it.

If they are serviced properly, they last a very long time.

Just read the PMA procedures. I have posted them before. They aren’t hard to find.

You can still get it. It’s call CRC red brake parts cleaner.

A hangar neighbor was doing landing practice at a field south of here. He told me about a Mooney with a student and an instructor. They went around 3 times because they couldn’t land on a 3500 foot runway. The blind leading the blind.

It is a mixed bag. If you are the only one flying the plane and you know how the controls are rigged and feel, I agree a bit of cushion is the best way. That way you get the full throw out of device you are controlling. On the flip side, I used to rig my prop control with some cushion. Every time my ex partner flew the plane, he would push the prop control all the way in. Once he actually told me how hard it was to get full RPM. He was pushing so hard that he was pushing the cable swivel at the end apart. I told him repeatedly to just gently push the control in till it stops. He never got it, he always pushed it to the stop. So I had to rig it with no cushion.

It’s hard to imagine what could fail in the scavenger pump. At worst, they would slowly loose effectiveness. I have three EBay scavenger pumps of different vintages. They all look new inside. The only thing that seems to fail is the oil seal. New ones are $5.

You are correct. I’m sure they got PMA for the new parts they are making. They or anybody else could get a PMA for new gears. They would have an advantage because they already have a quality system in place. That is half the battle.

I think cellphones do a lot more damage to our children's brains then the lead we put into their bodies, but that is just my opinion.

Good luck producing an aviation quality ultra reliable low volume actuator for $500. Just the NRE for that actuator will be hundreds of thousands of dollars. You have to spread that over how many actuators a year you are going to sell? The actuator will have a custom motor, custom gearbox, custom screw. Do you think you and your vendors will be able to support these new actuators 50 years from now?

I usually install the pivot bolts loose, then tighten the belt, then tighten the pivot bolts. The alternator should be tight. If the pivot bolts are loose, it will wear the pivot bolts and bushings rapidly.