PT20J

Assuming (likely) that the SIM itself is not malfunctioning, and is installed and timed properly, there are three possibilities: 1) If the SIM has a bad power or ground connection (be sure to check the fuse holder) that causes power to fluctuate, it can shut down and reboot. This will cause it to affect all cylinders simultaneously. 2) If there are voltage spikes on the power line greater than 40 or so volts, it will cause the SIM to shut down and reboot. This has only been seen on some 28 volt systems. Again, it will affect all cylinders simultaneously. 2) If there is a problem with an ignition harness or spark plug it can affect one cylinder. Since you have replaced and gapped the plugs that would tend to rule out the plugs. I might test the harness especially since it is new and untried. Skip

Oh man, this is making me travel back in time to chemistry class. I hated balancing equations, but his one is pretty simple. Avgas is a complex brew of hydrocarbons and other chemicals, but to use the octane example, complete combustion would combine the octane with just enough oxygen to result in the production of only carbon dioxide and water. 2C8H18 + aO2 =bCO2 + cH2O Balancing carbon: b=16 Balancing hydrogen: c=18 Balancing oxygen: 2a = 2b + c, or a =25 I'll let someone else figure out the weights Skip

I don't know about other models, but the J manuals don't get real revisions. Mooney just embeds comments in the pdf files. But there is no revision control on this so you can never be sure you have the latest embedded comments unless you order a new one. Skip

Smart move to test the bushing before replacing it!

I wouldn’t operate the engine until further investigation. I had a oil control ring break and it took out the cylinder and piston skirt which ran metal through the engine including contaminating the connecting rod big end bearing. It had been getting about 2 hrs per quart since I bought it. Filter, borescope, compressions and recent oil analysis were good at prebuy. I flew it about 25 hrs and it was running well. We discovered the damage at annual when the #4 compression had dropped to 56/80. At this point, we found metal in the filter and part of the ring in the suction screen. We didn’t investigate further than pulling the cylinder since we discovered that the cam was also spalled. I replaced it with a factory rebuilt A3B6 and had the prop resealed and the oil cooler overhauled due to the metal contamination. The point is that if a stuck ring breaks, it can do a lot of damage. Skip

Mooney put the marker beacon antenna in the belly above the fiberglass belly panel and the 121.5 MHz ELT antenna folded into the dorsal fin on my ‘94 M20J. I think the 406 MHz ELTs require the antenna to be vertical, though. I’ve removed the ADF antenna, but I’ve still got GPS, Aspen, ELT, 2 comms, nav, stormscope, DME, and transponder. Starting to looks like an AWACS Skip

Bruce Jaegar came up with an idea that makes the windlace installation easier. He applies double sided tape to the “fin” to hold it in place while you find the screw holes with an awl. But worse than windlace was replacing the weatherstripping on the doors. Getting all that old glue off - now that was miserable. Skip

I tried the LED post and glare shield lights. The problem for me is that I like to keep the cockpit pretty dim at night and the LEDs don't dim nearly as much as the incandescents. Really, you need to change the dimmer type from current control to pulse width modulated. There are PWM STC dimmers available, but that's more work than I wanted to go to for the few hours a year I fly at night. I'll save that for when I do a major avionics upgrade someday. Skip

I would think the cat whiskers would have the lowest drag because they have such a small area. I would think that the towel bars would have the highest because circular cross sections are draggy. Both are ugly, though. The more aesthetic blades should have drag somewhere in between, I'd think, because they have a fair amount of wetted area. Also, I'd expect them more sensitive to mounting -- you'd want to get them at the zero-lift AoA at cruise. Perhaps @blueontop might have some better insights. At any rate, I am always impressed with Byron's workmanship. Skip

Just for reference

I don't know if the earlier models had shims, but with the M20J, you need to be careful to note the shim thickness/locations. If you just let them fall out on the hangar floor, you'll spend a lot of time getting the spinner to line up with the cowling. Skip

That ST-115 tool is $1419.00. I might consult with a nearby engine shop. Also, if the problem is that the bushing is turning in the flange hole, maybe you need an oversize bushing. Skip

How are you measuring TAS? Mine seemed slow and I did a few GPS 4-way tests and found that the airspeed indicator was low by about 7 kts. I checked the pitot system and found a leak at the drain. Might be worth checking. Skip

It's a function of the regulatory requirements of the country where the aircraft is registered. Some countries use the UIN (a.k.a Standard Location Serial Number Protocol), some use the ICAO Mode S code, and some (like the US) allow either. In the US, if the UIN is used (which is most common), an N-number change only requires an update of the NOAA registration. However, if the ICAO code is used, the ELT would have to be reprogrammed with a new code. E-04-Programing-Manual-Rev-1.3.pdf An N-number change would also require a Mode S transponder to be reprogrammed with a new ICAO code obtained from the FAA when the new N-number is assigned. The log entry for this appears incomplete as it only shows that the Flight ID was changed. The GTX 345 will transmit both the ICAO code and the Flight ID. For GA, the Flight ID is typically the N-number but the two are actually unrelated. Flight IDs are commonly entered by airline crews to identify as a specific flight (e.g., AA317). Here's additional info from the FAA: Resources - Notices - FAA - FAASTeam - FAASafety.gov.pdf Skip

I did some more research. It turns out that some countries use the 24-bit ICAO identifier (same as mode S transponder and paired with the aircraft registration number) rather than the UIN (which is paired to the ELT serial number). The US uses either. So, it is possible that the airplane was originally registered in another country as was noted by Paul, or it is possible that the ICAO format was used in he US for some reason. There is an international database at www.airframes.org. Skip

1. It’s a hose: 2. Here’s how Mooney mounted them at the factory. Note that Mooney mounted the transducer with the wires down although Flowscan specifies wires up. I looked into this and the reason is because there is a vent to allow vapor to escape when mounted with the wires up. Unless you have leaks that allow air to get into the fuel lines, it doesn’t seem to make a difference. Here’s a picture of an installation without the factory bracket using adel clamps on the intake tubes that Byron @jetdriven did on his airplane. Skip

Proof that you cannot win

Just ran across this: http://www.nar-associates.com/technical-flying/impossible/TurnbackValidation.htm Skip

That sounds right. There should be timing marks on the back of the ring gear at TDC, 20 BTDC and 25 BTDC. To set the crank angle, align the appropriate mark with a straight edge placed along the crankcase parting seam.

A 406 MHz ELT has no concept of N-number. When activated, it transmits a 15-character hexidecimal Unique Identification Number. You are supposed to register the ELT with the appropriate authority for the country where the airplane is registered, and that's what links the UIN to the aircraft registration number and your contact information within the registering agency's database. Here's the installation manual for a popular ELT. E-04-Manual-single-page.pdf Skip

With the crank pin positioned as shown, the piston would be half way between TDC and BDC. I would rotate the crankshaft to #1 TDC -- there's a mark on the back of the ring gear for that -- and then rotate the drawing 90 degrees CCW for reference. Skip

I seem to recall some saying that this joint can be failure prone. My 1994 M20J has heim bearings on both mixture and throttle. See Note 1

That's an odd installation. Normally, the fuel flow transducer goes between the fuel pump and the servo inlet. Also, there are not supposed to be 90 deg elbows at the transducer. Skip