DC_Brasil

Let me tell you my POV. I have been passionate about aviation since I was a little kid (I am 41 now). I got my PPL almost 10 years ago and basically flew the flight school planes or a rented the local club Arrow here and there. Finally I've reached a point where I could indulge my dream and started looking. Found a beautiful 1990 M20J that had the original panel. I knew what I wanted: I wanted to fly, take my family for a few expensive burgers, but wanted the most gizmos my wallet could afford. I know I'd not be compensated for the installed technology if I ever decide to sell, but I am not buying my Mooney with that intent. I want to Fly. I want to shoot IFR approaches. I want to be safe. I want to be current, modern and fun. So I spent the most I could afford (and the most that would not lead my wife to commit murder ahahahhah) and put a G3X, G5, GFC500 and a GMA245R (the GSB15 was complimentary by the shop). The plane is used and has its squawks, old GPS and NAV/COMM, very beat out interior... But last week, flying to the coast with my wife, I can definitely tell you: I am living my dream.

Can anyone share pictures of the outer and inner fuel sender installations, wiring and grounding? My R fuel sender is intermittent and I want to take a look

I did that yesterday. Specially because the Concorde website listed certain serial numbers as appropriate for the RG24-15 and/or RG24-11. FWIW, I have email Frank at Mooney some times and he has always been very fast and helpful in his responses. He sent me the information regarding that "Concorde battery retrofit". It refers to the suitability for all 24-3000+ serial numbered M20Js to use the RG24-11/15 batteries plus the need for a 1.5lbs adjustment in weight and balance if using the -15 battery, which is heavier. I ended up ordering a RG24-11M, which was more readily available and had faster shipping. It should arrive next week and I'll get a tech to help me check all grounding and make sure everything will work. The battery technician really thinks there is a high likelihood my grounding should be ok. From what he could see in the battery tests they ran, there was an internal short and it would explain the huge negative current. If the short in the battery is intermittent, the ammeter could show large swings as the current draw spikes when the short is present, just like I experienced in flight. For example, I saw currents fluctuating from +2 to -290 amps. Also, the battery overheated when they ran a charging test. If one or more battery cells are shorted, they will convert charging current to heat (that's what I was told). However, next week, when the new battery arrives, I'll run some tests. Thanks for the inputs to everyone. This forum is a life (and pocket) saver.

I'll make sure to review all of that. I just saw at the Concorde website that specific model is 12V. My plane is 24V. Now I am looking at the Concorde website that the two 24V batteries (RG24-15 and RG24-11M) are not suitable for my plane's Serial #. I have emailed Mooney and see what comes back.

Hello everyone. I had a technician test the battery and it was in very bad shape. So I guess I found the source of the problems. My battery was a Gill G-243. Can anyone help me find a list of suitable replacements? The tech advised me to get a sealed battery. However, I really don't have any knowledge about the battery and electrical systems.

I actually don't recall... will have to check that.

My first guess was a bad battery. Will check that for sure!

Would that explain the crazy ammeter readings? Sorry but I am very inexperienced with electrical circuits.

Hi Eric. I did a mag check before takeoff and in flight and it worked fine. Engine ran smoothly and EGTs responded properly to the single mag.

Let's get the collective wisdom rolling My M20J is fresh out of the avionics shop after installing a G3X panel. Last week when I flew it, the R wing fuel gauge stopped working. Well the fuel senders are old and I am contemplating a switch anyways. The very next flight, when I tried to start the engine I turned the key the plane seemed like the battery was low. I thought it was odd but maybe I spent a little too long updating the navdata with the engine off. I started it with an external source and went flying. Everything seemed normal so I took it on a 2hr XC flight. Today, flying back home I experienced the same behavior and had to use and external source to start up. Now, both COMM radios had an interference of a quick rhythmic "popping" sound. Additionally, in cruise I could see the ammeter was showing some crazy readouts, going from -30 to -290 amps!!! After I landed the ammeter showed a reasonable +2 amps. I tried turning on and off various systems and lights to see what I could find but no clue. Nothing particular happened. I suspect something is shorting the system and draining the battery. Perhaps the fuel sender line (it may have nothing to do with the electrical problem but what the hell)? Any thoughts? Here are some pictures.

Yes, that's personal but you actually get used pretty fast. The upside is that the G3X is as left as possible (and in my case, as high as possible) freeing more panel real estate for future upgrades.

The original Gear Override switch in my plane was to the left of the gear lever. I also thought it made sense to put it below and save some lateral space. Yes, the Cygnet switches were placed in the same mount. Now I need to try and fix the R fuel senders. New picture, flying today to Rio de Janeiro (SBRJ). Navigating with the G3X and GFC500 is a breeze!

Finally in the air! After solving some quirks after the upgrade, my J is finally flying. Just loving the new panel and especially the GFC500 autopilot. It reaaaaly makes things easier. Next steps for 2025 should be a new GPS, transponder and most likely CiES fuel senders. After a turbulence bump my R fuel sender stopped working (it was working fine in previous test flights).

Great webinar from Mike Bush about valve sticking. https://youtu.be/7ohsVvYbAaQ?si=nLwJ9cTg9ANzh3kE

Can you share the video and perhaps a picture of how your left aileron looks now? I am having the exact same issue: a very intense right roll tendency after the shop rigged everything according to manual specs.

@Stanton R thanks for the warning. The servos had indeed been rigged the wrong way and the YD behaved as expected: Dutch roll. However two other things were wrong during the test flight and the shop is assessing the issues: 1 - whenever engaged, the Autopilot commanded very aggressive right turns, even on ROLL lateral mode. 2 - the G3X tachometer is showing less than the real RPM. I guess this can be some incorrect config of the magneto type (Rated RPM is 2700 and the G3X is showing 2470). Having these checked today.

@Stanton R thanks for the heads-up. I will definitely talk to the mechanics about it. Wednesday I was there to test everything. Pitch, roll and trim controls worked on the ground. I didn't test the YD, but will do tomorrow morning. Do you have any suggestions on how to actually test if the YD is working correctly? I have never flown with YD.

Almost ready! Went to the shop today. The idea was to review all installation and do a thorough runnup and a quick test flight with the mechanic to review the GFC500 autopilot. All avionics working but we had a malfunction with the voltage regulator. Having it checked the next couple of days and see if we can fly the plane Saturday morning. However, we got to spend some time playing with the new screen. The G3X is indeed a very nice piece of equipment.

Thanks everyone for the very useful insights. I'll get right on it with the guys at the shop.

Hello everyone. My M20J is in the avionics shop finishing a panel upgrade. When the guys went to drain the fuel tanks to calibrate the fuel sensors with the G3X, the fuel drain sump valves on both wings had cracks. Since they are hollow screws and rather fragile, I'm guessing the previous guys that worked on the plane may have over-torqued it when screwing the valves in place. These were SAF AIR 53S fuel drain valves. The SAF AIR 53S are direct replacements for the F-391-53S original fuel drains. I bought a couple of F-391-53S from Aircraft Spruce and they already come with new o-Rings. When installed these drain valves were very slowly leaking. It is a very slow and subtle leak, not even dripping. The drain valve gets wet with fuel. The shop tried to use two o-rings but the slow leak remained. Anyone has any ideas how to mitigate it? It is the correct piece, correct PN with a brand new o-ring. Should be a good fit, right?

Hello! My M20J is finishing the panel upgrade next week. I'll have a freshly remo ed and working VSI for sale. I live in Brazil but could check how much a FedEx or DHL shipping would cost if you're interested. Pm me.

What a sweet setup!! My plane's is in the shop for un upgrade and, since I had a GNS430 and had read great things about the GFC500, decided to go with a G3X setup (1 10" screen + G5 backup). My reasoning was mainly because of service and support availability but also looking at upgrade plans. I live in Brazil and it will be way easier to find support and service for Garmin than any other brands. Additionally, since my budget didn't allow for me to upgrade the GPS now, going all Garmin will make it easier in the future (albeit somewhat expensive) to replace other parts of the panel. And as @Pinecone wrote: having the panel made the way YOU want is part of the upgrade fun :-)

I have found that PDF. I am worried (maybe unjustified, though) because I suspect Brazilian aviation authority (ANAC, our FAA) will need to update my CA with the new GW. My A&P said that they need to file a request and add supporting documents. My worry is that when someone sees that both the Service Letter and the M20J Type Certificate Data Sheet tell that the GW increase is approved when in compliance with Mooney drawing number 940071. I am concerned they'll look at it and ask:, Ok, where's this drawing in your request? We don't see it, so we can't verify the procedure has been followed.

Would you please ping them in this post?

Soooo... anyone has the Mooney drawing number 940071? ahahahahah this seems to be the biggest mystery in all of this.