Philip S

1976 M20C model here. Last winter I had a gear issue where on departure I would get a "gear unsafe" alert light and warning horn after raising the gear. Sometimes this would result in a low voltage alarm from the gear motor continuing to run, but not always. It is clearly temperature-related as it does not happen in warmer temps, happens intermittently around the 50-60F range, and happens fairly consistently below 50F. I know its not simply a switch problem, as on one occasion when I continued my departure despite the alarm, my cruise speed was about 10 knots slow. When I slowed to gear speed at altitude and recycled the gear to the up and locked position and the alarm quit, my cruise speed returned to normal. I am fairly certain that the gear is not fully retracting as a result. I sent it to two local mechanics last year who have Mooney experience. The first refused to leave the plane outside in the cold to test the gear, as his hangar is heated and he didn't want to jack the plane up outside, but he found no issues in the heated hangar. The second, who evaluated the gear later in the spring when it was warmer, could not replicate the issue and said all the measurements were in tolerance. I have done several low passes with a Mooney pilot ground observer who can see no issue from outside, but again it was warm then and I didn't get a warning during the low passes. The issue resolved itself over the summer, but now that temperatures are cold again it has returned. On a recent flight I took off at about 65F without issue, and only had the issue return when I was visiting the DC area. It promptly resolved on my return flight to warmer temps. I suspect a donut issue as based on the serial numbers they are original to the airplane, and temperature tends to alter the expansion properties of rubber, particularly old rubber, rather dramatically. I've never had an issue with the gear coming down or locking properly. Yet. Anyone had experience with this issue before? Sound like donuts? My debate is between continuing to investigate, versus simply replacing the donuts. I called my A&P who can't take a look until March. If anyone knows another experienced Mooney mechanic in the southeast who can check me out sooner I'll be all for it.

So there is a vent drain! I always wondered how Mooney expected that to be watertight or deal with rain. All makes sense now. Will pull headliner and inspect. Thanks folks.

I fly a '76 C with some J-style mods. I'm a rare poster here, but I really love Mooney, my plane in particular, and fly often for travel. I've noticed some leaks, damp spots on the headliner and on a recent occasion the rear seat carpeting after heavy rains when parked on the ramp while traveling. I keep it hangared so I only notice it on trips when I'm parked out and it rains very heavily- a rare event-but corrosion is the enemy of airplanes so I'd like to find a solution. I inspected my roof, antennas, etc, and I'm fairly convinced the leak is through the windscoop on the roof (which is definitely closed when leaving the plane. I made it a post-flight checklist item when this happened once before). I have a Bruce's Custom cover from the prior owner, but it's kinda bulky, takes up room that I need when I travel (right seater is a lady), and is an annoyance/time sink to set up and take down while dealing with bags, windy ramp, etc. Anyone out there found a nice quick solution? Maybe some clean white rigging tape over the scoop only when rain is forecast? A sticky rubber/silicone mat to lay over the scoop? Or quit being cheap and just pay for the hangar overnight?

Done! Thanks. It's a little different on mac, but you got me close enough. Also-the rim is fine, and the tire probably. But considering a new tire is about $100 that sucker ended up in the dumpster. Cheap insurance. Now I just need to figure out how to replace the mains myself. They look okay, but I'm not doing this again any time soon.

Oh I grew up in Louisiana and lived in Alabama the 7 of the last 8 years. I'll be back there permanently this summer. Alabama sun is about my usual, but that don't mean it ain't hot. Ah-more learning opportunities. Forgot about the other kind of valve stem. Now if I could only figure out how to edit post titles... The tow was about 3/4 the length of the runway, times 2 since I had to go back on the taxiway. It was a first for the flatbed driver in addition to the pilot. I tried to use the tow bar and a pickup truck, but that wasn't happening. Made me wonder, what does one usually do for a nosegear or main gear blowout on a runway? A busy runway? We were on the pavement for 2 hours and no one landed, but it could have been very different if this had happened at our destination airport of KNEW.

Had my 76 C model about a year or so. Never liked the looks of the nose gear valve stem from when I first saw it. The stem leaned against the hub, and the side load on the stem just didn't seem right. I had to pull on it to get it away from the hub far enough to add air (sorry no before pics). Asked my mechanic to check on it at a recent annual-said it was okay. It's my first airplane and I've not even got 400 hours yet, so I didn't press the issue. I'm a noob here so what do I know. Blew the nose tire last week on a rather smooth landing. The stem was ripped clear of the tube (pics below). Moral of the story: its your airplane and your ass in the seat. Don't accept something you think is incorrect. The silver lining is, I learned how to change an airplane tube and tire, and now I have a lovely 90 degree valve stem that doesn't lean against the hub. Plus I met a wonderful airport manager who helped me out with getting the plane jacked up, tire mounted, etc. Can't thank him enough. You do meet the best people in aviation. I saw a similar thread earlier, but if you have a straight stem on your 5-5.00 nose gear tire, and it leans against the hub, my low-time PPL-only thoughts are to change it out unless you enjoy overnight shipping charges and tire changes in the Alabama sun.

I have run 2.5 hrs on a single tank and added 23 gallons afterwards, and it sure looked like there wasn't much more than a gallon left in the bottom. But of course that can be very deceiving in a low, sloping tank. I have never had the guts to run a tank dry in an airplane. I'd be a little worried to do so to be honest. Do you guys routinely run a tank dry? Do your passengers ask questions when things get quiet out front? I'll probably run it near dry and then drain the rest, then fill to brim to get an idea of what the true volume is. Thanks for the suggestion. I have standard caps without a door. I definitely want a fuel flow gauge with totalizer. I see JPI makes a decent one which should talk to my existing JPI 700, or there is a standalone option the FuelScan 450. Either option is cheaper than upgrading to a more modern engine monitor. The previous owner did such a great job on a really cool new carbon fiber panel I'm a little hesitant to rearrange it for the big displays of the 900 series. I'm leaning towards the FuelScan but might fly a little more before making any decisions. I've only just gotten through the first annual. All the advice is great and greatly appreciated. Thanks all!

The tanks were resealed which I think is the source for the reduced fuel volume, but I'd have to dig back through the logs. The filler area is placarded "24 gal usable." The way I was running 100F ROP gives 9.2 gph. Start/clearance/taxi fuel, waiting for the texan2s to takeoff before me, mild headwinds, etc. Here's a recent flight where I landed with 7 gallons/45 min remaining. It was a clear and beautiful day with 13 knots wind forward of the beam otherwise I'd never have flown this far before a fuel stop. Yes, the tanks were filled to the max prior to departure. https://flightaware.com/live/flight/N7048V/history/20210523/1500Z/KNEW/KCDN Total distance 635 sm. I would have rather landed with at least 1 hrs fuel in the tanks (my general policy, but I'm experimenting, carefully, with trying to get more range). I don't think I'll ever be comfortable flying this far again, especially if there is ANY weather around. This flight was the impetus for my initial inquiry into how I can operate more efficiently to get more range from the plane. I'll try leaning more knowing at 10,000 there's no red box, its just a bad MP gauge, and see how my fuel burn changes. REALLY appreciate all the responses from you all. This forum is truly a wonderful place.

Perfect. This answered my main question: if at 10,000 I'm definitely making less than 75% power, I'll lean to peak and make sure those CHTs are happy. Thanks all. MP gauge overhaul in the offing. The tach is separate, a digital Horizon model. It seems spot on, but perhaps I'll have it looked at as well since I'm doing all this fiddling with power settings.

I have a JPI 700. Four probe CHTs and and four probe EGTs. I'd rather one of the newer ones, but mostly for the ability to easily download the data to my computer from the monitor for graphing trends. I haven't delved into the various adapters and windows programs to get the data off the JPI 700 yet. Debating upgrading to something easier to use with fuel flow.

Seems like the gauge is off then. I figured so. Regarding the RPM setting I guess mostly because Mike Busch says so, or for another reason its quieter. I've played with higher RPM, but it doesn't seem to generate much more speed.

Very good point. I should have been more specific. I'be been running 100F rich of the peak EGT I can achieve before significant engine roughness. I usually peak about 1470, a little leaner will sometimes get me 10F beyond peak EGT at 1460, but its rough enough to make the passengers ask questions. Perhaps this isn't the best system. I welcome any other ideas.

Engine savants, I have a 76 C model with an O-360 A1D. I have noticed the numbers I get in flight differ from what you might expect from the performance charts in the POH. I typically fly about 9-11,000. On a recent flight at 10,000 my power settings were WOT, with just over 22" MP and 2350 RPM. The performance chart for 10,000 shows a max MP at 20.2" while the 7,500 chart will get you 22.5" This suggests I'm making about 75% power at 10k, which seems improbable to me, and apparently the guys who wrote the performance charts as well. I can't seem to get the plane to operate LOP despite fiddling with carb heat or tilting the throttle plate a smidge, so I usually am just over 100F ROP. I'd like to be able to operate near max efficiency at times for longer range (only 48 gal usable-which is barely 500 miles or so at 9 gph), and thus am interested in leaning more-say to at peak EGT or roughness, which with a low enough percent power should be safe. I want to stay out of the red box of course while trying this, which means going higher to reduce MP without closing the throttle. I guess my questions are 1. Is 22" MP a reasonable number at 10,000 or is my gauge telling me I'm making more power than I really am? and 2. Since even at 10,000 WOT, 22" and 2350 RPM, leaned just shy of engine roughness only gets me about 365 on the #4 (hottest) CHT, does any of this really matter? and finally 3. Should I give up trying to get this thing to burn less than 9 gph to try and get some more range and fly 100F+ ROP and forget about it? Thanks in advance for any wisdom you all may have.

This is a little after passing Mt. Mitchell. I’ve been able to find smooth air between 10 and 12k. But have definitely hit my head while finding it. 78 knots near the nose really puts your speed in perspective (and makes me wish for longer range tanks). I usually pass south of the mountains but maybe a northerly route would be preferable as icurnmedic suggests.

It’s the SWTA. Sounds like they are no longer around.