RideOrFly

Good thought, and yes, the injectors were cleaned.

Check with @oregon87 about this. I messaged him recently about upgrading my UBG to the CGR-30p and they're offering a very attractive credit to do so.

I'm in the middle of what's turning into a maintenance nightmare, and would appreciate any thoughts/input on the situation. The plane is a 79 M20J, 600 SMOH (150 of that since I bought the plane in May 2022. I don't have an engine monitor and while I'm trying to learn as much as I can, I'm definitely much more pilot than mechanic. I was flying regularly, and the engine has always been extremely smooth. Compressions in the high 70s consistently, always idled smoothly and performed flawlessly. This past summer life got busy for a while and I didn't fly for several months. Before taking it back up, I had the oil changed and battery replaced. I went for my first flight back, everything was normal from start up through one lap in the pattern. On my second takeoff, I had a partial (most) power loss just after rotation. It wasn't rough, just lost power. Fortunately, it came back after a few seconds and I flew the pattern and landed. While taxiing in, it was smooth and normal. I did a full power run up and everything was normal. I shut down and sumped the tanks again--no water. (the plane has had problems with water in the right tank before, but interestingly not after sitting out for several months.) I was still feeling uneasy about it, so I had the mechanic check it out. He found rust particles in the fuel system and the fuel servo had some rust internally. So, he replaced the fuel servo and divider. After installing the servo and divider, he said the plane ran rough and wouldn't make more than 1200 RPM. I wasn't there that day, mechanic suspected there was a problem with the magneto. It's a little overdue for IRAN, so we sent it out. It got the standard service and was returned. Mechanic installed it and said everything was good. I went out last week after getting the good news. I noticed that the mixture control is now EXTREMELY stiff. I don't have a ton of experience, but I've never seen one anywhere close to this hard to move. the plane started fine, but immediately started running rough and then popping (afterfire?). My wife caught a video of it and you can see the flames coming out of the exhaust. Lean/rich didn't seem to change anything. Mechanic took another look the next day and said that everything looks ok, that the popping goes away above 1200 RPM and isn't hurting anything. He checked the plugs again (which were just cleaned) and of course they are black. Compressions were all in the high 70s. We spoke this morning and I asked if he had set the idle mixture correctly. Interestingly, he had one run in which the RPM went up 50 at idle cutoff and then on the next run it went up 200 RPM. I asked him to repeat this and make sure it was correct/consistent and see if the problem improved. He called me back an hour later saying that this time he ran it it was running rough and popping again. He noted EGT in #1 cylinder was 900-1100 while the others were all 600-700. Based on this, he *thinks* I have a sticking exhaust valve and *guesses* that it's on #1. He's recommending pulling that cylinder and sending it off for repair or OH. Here are my specific questions right now, though I would really appreciate any thoughts that you all have: 1. Is it normal for the mixture control to be so stiff after installing a new fuel servo? 2. It seems exceedingly unlikely to me that the plane would suddenly develop a stuck valve immediately after the other unrelated repairs were done, am I wrong? 3. If the exhaust valve is stuck, I can see where that would cause the afterfiring, but shouldn't the EGT be lower, not higher? And wouldn't the compression be lower on that cylinder? I know that's a lot and I really appreciate any advice/insight.

I do now. Thanks for the reference, that’s what I needed.

I've heard mentions before about adjusting the stall warning assembly. If one wanted to have the stall horn activate at a lower airspeed, would that require loosening the inner screws and then moving it up a bit?

Ah, I see. Makes sense now. Thank you, sir.

I'm needing a new insert (part #31 in the illustration) for my door latch assembly. I'm confused as to exactly which part # I'm needing from the list...part #914028-015 and part #310304-005 are both called "insert" and there are no notes distinguishing between the two. Any ideas? Plane is a 1979 M20J, S/N 24-0833.

Audio panel is sold. Prices reduced on everything else.

Geez. I really hope my mechanic could spot something like that.

That was my suspicion, but didn't really have anything to back it up. I agree it doesn't make much sense for the alternator brushes to cook the VR. I'm going by the shop in the morning to take a look and talk with the mechanic some more. He did mention having checked the field wire with the initial "troubleshooting" but I'll have to check about the master switch, etc. I'm not the most mechanically inclined person, but if I can't trust the shop, I guess I don't have much choice other than to figure it out. Glad you got it figured out...I wish I had more time and a better location to work through this kind of stuff. I'll get a look at the connections and order a voltmeter at least.

Thank you

I'm chasing down an electrical problem and I'm hoping someone on here can offer some advice. Running the checklist in flight is about the extent of my expertise at this point. 1979 M20J, roughly 5500 TTAF. Plane was down for a few months getting avionics. Annual was done immediately after. On my first flight after annual, my brand new AP disconnected and voltage light started flashing. Ammeter was reading steady at about -10. Everything had been normal during the run-up. Resetting breaker had no effect. Battery voltage dropped down to around 10. I took it back to the shop that did the annual. They tell me that the battery holds a charge just fine, but that my VR is fried. I ordered a new Zeftronics VR that was installed yesterday. Mechanic did ground run today, and problem persists. He checks the alternator and now tells me that the alternator brushes are bad, and that could have been what fried the VR. Unfortunately, the alternator doesn't have anything on it indicating what brand, part #, etc. it is. *edit* I finally found the part number for the alternator in my logbook, ELS-ALY-8520RS. A few specific questions: 1) Does this sound like a normal approach to troubleshooting a problem? It seems like checking the alternator out would have been part of the initial assessment. 2) What are the odds that this is the original alternator? 3) Any idea how to figure out what brand/model it is? 4) Should I just replace or overhaul the alternator at this point, or is replacing the brushes a reasonable thing to do? Any input appreciated.

No way I would fly with or recommend flying with scopolamine. It can cause visual disturbances, sedation, and (rare) neuropsychiatric side effects.

Big fan of manifesto...haven't read the others yet.

I bought "The Complete Advanced Pilot" by Bob Gardner for commercial. I really wish I'd had it for instrument. Gleim test prep + this book would have been gold.

I have some avionics that were removed with my recent upgrade. These were working perfectly when removed. All prices OBO, shipping negotiable...keep in mind that I just blew all of my fuel money on new Garmin stuff, so I could use some help! KI525A-$500 $250 KG102A-$500 $250 KMT112-$100 $50 KA51B-$100 $50 Or $500 for everything above KMA24 and intercom-$100 SOLD

I contacted Century's technical support people a few months back and they went out of their way to help me diagnose a problem over the phone. I realize it won't help you diagnose the problem, but I'll have a Century 41 coming out of my plane in the next few weeks. Hoping to sell it to someone who needs some parts. Let me know if you're interested.

I have this fantasy about sooner or later turning my J into the nicest one out there. That bar just got put a little further out of reach

The MAPA pilot proficiency manual is a phenemonal resource.

Thanks for the input. I went out today to start it up. When I turned the boost pump on the gauge didn't move at all even though I could hear the pump running. It cranked up right away without any problem. The needle still hadn't moved. So I tapped it with my finger and instantly had normal fuel pressure. I think that pretty much clears it up. Between this and my kinda sketchy annunciator panel, a JPI 900 is looking very attractive.

Still new to airplane ownership...plane is a 1979 M20J. I was out flying last night and everything was looking normal for an hour or so. After a touch and go, I climbed up as usual and turned my boost pump off. I checked the fuel pressure immediately after and it was down at 5. I turned the boost pump back on and turned back toward the runway. The fuel pressure didn't change. The engine sounded completely normal and the performance of the aircraft was also normal. After landing, I tried turning the master off and back on. The fuel pressure came back to 5 and stayed there. Then I shut the engine down. When I pulled the mixture to idle, the fuel pressure went back up into the green immediately. I restarted the engine and it stayed in the green. Does this sound more like a gauge malfunction or some actual problem? It seems like fuel pressure that low would have caused some symptoms at full power (during takeoff), but it also seems like a faulty gauge would more likely read nothing at all, rather than a specific number.

That did occur to me. Seems like I need to either spend enough to make it worth it or nothing at all. Pretty much what I suspected. I would be inconsolable if I dropped $5k on a feature and then the AP crapped out a year later...and it sounds like that's an "when, not if" kind of question. Thank you for that. For now, I'm planning on doing nothing for a while and see how I like everything as is. My experience with the GFC 500 is the only time I've had with an AP and I'm worried that I'm spoiled now. The VNAV function was remarkable. It did have a problem disconnecting (twice) on approaches in not-too-significant bumps, but I'm not sure if that was an AP problem or not. The big money problem isn't really the GFC 500 by itself...it's adding the G5 to drive it, which leads to the second G5 to go with it. And it's got that VNAV function, so may as well upgrade the GNS to a GTN to take advantage of all of the features. And if you're getting a GTN, why not get the remote audio panel and transponder to go with it? If you give a mouse a cookie...

I have a 201 under contract and I'm thinking about some upgrades already. It has a Century 41 AP that works fine, but doesn't have altitude preselect and that's a feature I'd like to have. I see that Century offers a preselector for the 41, but I'm wondering how practical/rational of a solution this is. It looks like the unit is just under $5,000 and I have no idea about install time. I also worry about how wise it is to invest heavily in a piece of "legacy" tech. The other option would be upgrading to a GFC 500 (which I've flown with and loved) but that's a whole lot more money since the plane doesn't have a G5. Does anyone have any experience with or thoughts on this?

It's funny, I'm kind of having the same experience, the Mooney is the only plane I ever really got excited about owning. I don't *need* an airplane, so settling for something I don't really want doesn't make a lot of sense. Glad to know I'm not the only one.

Can't think of much that's more expensive than a cheap airplane.