J. mitchell

BTW there are only 5 million identified cases of COVID19 in the U.S. and 330 million people. It is difficult for me to believe the virus is slowing down the approval of an autopilot.....

Just an update on my comments on the TruTrak autopilot, now Aerocruze100: I sent an email to Bendix King and just received a note that all the paperwork for the STC for vintage Mooney Aircraft has been submitted to the FAA. No comment as to why it hasn’t yet been approved for our aircraft. So it appears the ball is in the FAA,s hands. If anyone has ideas on how to get the FAA to work faster on the STC please post them. I believe this autopilot would add significantly to our safety.

I looked at the TruTrak website earlier this afternoon and noticed that the Mooney pre order picture was no longer there. I am hoping that TruTrak has not abandoned our vintage Mooneys. When at OSH a couple of years ago there was a Mooney M20E, I believe, with a TruTrak autopilot installed. I was told to expect it to be available for my C model within 6 months...still waiting....

It appears that a number of M20C owners have experienced the same issue I have been experiencing. I would be glad to know if replacing the mechanical pump resolves the issue. Once again, thanks for all the thoughts shared. John

Guys, I really appreciate your thoughts here. I especially appreciate DXB’s comments that many C models experience what I have experienced with my Mooney. Both your explanations make sense. Thanks so much for your help with this issue. John

Thanks for the thoughts. I will be doing that. John

-a- That was one of our first flights with the new engine analyzer. #4 EGT had a loose connection. Pretty quickly tracked down. John

That’s what we are seeing. The first few minutes is with the electric fuel boost on, turned off and the fuel pressure drops. In this case I climbed to 4,500 MSL and at that point it was mechanical pump only. Yet all the rest of the numbers I believe look OK. There doesn’t appear to be fuel starvation.

Let’s see if this works. I am on a learning curve here and did not know just how much information is available. I did check fuel pressure and it is up and down on the climb. https://apps.savvyaviation.com/my-flights/22650/4380a0b8-5503-4b65-aa52-1e555a7d1556

A look at our flight back to AVL.

At 5,500 MSL in cruise. Still adjusting the K factor on fuel. Fuel pressure is fine in straight and level flight.

I really appreciate those thoughts. I spoke with my mechanic this afternoon and the issue of air in the line and perhaps in the mechanical fuel pump might be causing the problem. The engine does not appear to be suffering fuel starvation and now that I can see EGT AND CHT numbers, they are all where they should be. My fuel flow also reads where it should be on climb out and cruise when we lean. The fuel pressure returns to normal in cruise. We have flown about 10 hours since the EDM 900 has been installed. All the other numbers look fine.

I appreciate all the thoughts on this issue. When the issue is resolved I will post a note. We thought we had addressed the issue 2 years ago with a faulty instrument, but it is looking more and more like a weak mechanical fuel pump.

Thanks for those comments. Yes, the EDM 900 is awesome. In the climb with the boost on our fuel pressure is right up there too. I am becoming more convinced there is an issue with the mechanical fuel pump. I did see there was a mandatory service bulletin for a number of fuel pumps on certain 0-360 lycoming engines, but it didn’t include the engine in the M20C.

Yes, the electric boost pump does push the pressure up. It’s interesting that in cruise the pressure is fine. On descent and approach I get the opposite reaction, the fuel pressure is high and I am throttled back. I will be taking my a Mooney to annual next month, so the fuel pump will be checked out.