AndreiC

I am happy to put as much elbow grease into polishing/buffing the plane as I can, but every time I tried to do it the results have been disappointing. I don't know if it is my technique, the materials I use, or the fact that maybe my paint is shot. One option of course will be to just go to the guys that quoted me 5 AMU and let them do a small patch, observe what they do and how they do it, and see if I can do it myself (or if not, have them do it). One thing I was trying to gauge on the list here is if the 5 AMU price was within the normal range (given that someone said 2 AMU it seems to have gone up a lot, or that this place is really pricey), and what people thought, if 5 AMU was worth it or not.

I just saw the offer below from a company affiliated with Amazon, so presumably it is not a flaky one. I was wondering if this appliance could easily be adapted to push/pull a Mooney in/out of a hangar. What do you guys think? https://tools.woot.com/offers/superhandy-electric-trailer-dolly-14?ref=cnt_wp_0_27&fbclid=IwY2xjawG8BKNleHRuA2FlbQIxMQABHdiXibls7qtKarO_TRA6sBnI_Z4_F-ZGlGwzFAoSvkDhfg0abvYzF7quqQ_aem__gttZBtgh2uMc7lFdyfaoQ

I have been thinking about hiring a professional to do a two-stage paint correction (i.e., buffing) and ceramic coating of my plane, a 1970 M20E. My plane was last painted some time in the 1990's, and while the paint is all there and not chipping away, it is not exactly shining either. However, after talking yesterday to a guy recommended by @Sabremech, I was a bit taken aback by the price. They said to do the whole plane is going to be 5 AMU, and the ceramic coat will last about 2 years, after which one would need to reapply it (but no need for buffing again) at a cost of about 2.5 AMU. I had thought the cost should be closer to 3 AMU for the whole job, and maybe 1 AMU every two years. I was hoping to get some opinions from people here who have done it, and whether they thought it was worth it. With a paint job costing north of 25 AMU these days, I don't see re painting my plane any time soon. Also, another question. Can I perhaps ask them to only do the visible parts of the plane (i.e., no belly or underside of the wings), since I never look at how shiny the plane is underneath? That would be only about half the work, right?

My impression is that our engines fail in two ways. One is that they start making metal, eating themselves up relatively slowly. This kind of failure is easy to detect with oil filter inspections. Maybe to be on the safer side one would do more frequent oil changes on an engine that is past TBO (perhaps every 25 hours including the oil filter), at least in the beginning until one gets to know the specific engine. Possibly, and here from what I read the opinions vary on the usefulness, you could also send oil samples to a lab to be analyzed, and after 3-4 oil changes you could start to see trends in metals that appear in the oil change. (My understanding is that one oil analysis is useless, as the absolute numbers are not that important; more important are the trends over time.) But my understanding is that from the time the engine starts making detectable metal, it won't die catastrophically within 25 hours, so you'll catch this kind of issue in time (but head for an overhaul once it happens). The other kind of failure is the catastrophic failure: engine throws a rod or seizes up due to oil not reaching a critical part. My impression (and, again, I am not a mechanic so don't count on my opinion as being worth much) is that these kinds of things happen more from an improperly assembled engine (or one that is improperly operated -- for example if you get detonation) than from the engine being old. This is the "infant mortality" phenomenon. This is why people like engines with around 500 hours, since they proved already to be woking well. My understanding is that as you get past TBO, especially with an engine that has not been run much in the last few years, the odds of starting to make metal increase. One reason for this would be if the camshaft starts getting pitted from corrosion. (The cam in Lycoming's design is sitting high in the engine, so any oil that is on it drips down after a while and the cam is sitting exposed naked to the atmosphere.) Once corrosion starts to happen in the cam, the surfaces that are supposed to be very smooth get rough, and it is only a matter of time until it eats itself up. This is why people like engines that have been run frequently, at least 50-100 hours per year. Where in the country the engine has sat also has an effect -- dry Arizona is much better than humid Florida. Also, if the engine has already been through many hours (500+, certainly your 2000) this is less likely to happen than on a new engine: I was told that over time a thin layer of carbonized oil residue forms that protects the metal from corrosion. But of course even this cannot last indefinitely -- things rub against each other and wear out. For example flight schools (which fly their engines a lot, 500-1000 hours per year at least) frequently run their engines 3000 hours, so 1000 hours past TBO, with no ill effects. Another factor here is also that over time all kinds of rubber seals age, hoses can develop cracks, etc. This is another reason why Lycoming says that after 2000 hours *or* 12 years it is time to overhaul. Take what I wrote with a grain of salt, as I said I am not a mechanic and all my understanding comes from reading threads like this and also operating Lycoming engines for around 25 years. Best of luck.

Is this something that is happening because of the way newer cams/lifters have been made more recently? If that is the case, the OP's plane may not have this issue, as the engine is original since 1979.

I have been looking for the same kind of prop to replace my 3-blade McCauley on my 1970 E-model, and so I have quite a bit of information for you. (But I gave up on my search for the reasons below.) 1) You could buy the same prop that you have now, used/overhauled, for about $11k, from a guy in Las Vegas who deals in used props. My guess is it is not a great deal. I can get you his info if you want. Alternatively, you could possibly find for about $4-5k a used prop similar to the one you have, but with an earlier hub (not B-style), which requires periodic (100 hour) eddy current inspections. Probably you don't want this. 2) You could buy a brand new Hartzell Top Prop from @Cody Stallings for somewhere around $12-$15k, you need to check with him. I don't know if you need a new spinner with the new prop, but those can be had used for around $500. Cody is highly recommended by the Mooney community, and at this price it is probably a much better deal than the ones above. Some people complain that the Top Prop has a caution range where it is not recommended to operate the prop between 2350-2550 RPM above 24" MP which they say is a big enough inconvenience. 3) MT makes a nice three blade composite (wood + carbon fiber, I think) propeller that many people say is very nice, but it is quite pricey, probably around $20k my guess (no concrete info). I think the biggest advantage of that prop is that it removes the caution range of the Top Prop, and it is quite smooth from what I understand. 4) Many people do not like the McCauley 3 blade prop that is STCed for the E model (and I suspect also for the C). For this reason you can find quite a few of these used on barnstormers for very reasonable prices ($5-6k), in good condition. I think @Alan Fox for example sells a nice one for $6k, but check compatibility. The main complaint people have is that they say it a) robs you of about 35 lbs of useful load, and that weight is added to the front of the plane, which reduces your cruise speed slightly; and b) it is impossible (or much harder) to balance properly, resulting in higher vibration in the cockpit. a) is definitely true. But for b), I have that prop and had been complaining about vibration, and it turned out it was caused by some slightly loose engine mounts, which when corrected improved things a lot. Also, the prop specialist at Poplar Grove told me that it is very important that the prop be mounted following McCauley's instructions to the letter, and that he sees many such props that are not mounted correctly, contributing to further vibration. He said in his experience he can get these props to be very smooth unless there is something technically wrong with the prop or the engine. I will be going to them in 10 days to have them do their magic and see how that works. I can report back. BTW, you did not tell us why you need a new prop. If you have a good condition used prop with a B-hub but with blades that do not pass overhaul limits, you can probably find somewhere serviceable blades to put in that hub for much less money than the $11k the guy in Las Vegas is asking for. A good B-hub is worth quite a bit of money as well, probably north of $3-4k.

If you are in the Bay Area, Top Gun aviation at Stockton is a very good shop for Mooneys. They are very busy, but you may be able to get them to look at and give advice on the plane you're looking at.

I tested this yesterday. The Power Boost makes no difference — the behavior is exactly the same with it open or closed. Any further ideas?

@MikeOH But I still don’t understand how the power gets to the gear down circuit. If I understand the logic correctly, when the gear is up, no power comes from the gear up limit switch (U). Then the power boost line (P) is not energized, so even though the power boost is on, the return line PP is also not energized. This may work if, as @1967 427 said, there is some residual current coming from the gear down limit switch.

Yes, I *think* I was using Ram Air. I also suspect the LED’s used were non polarized. Do you know of a source for polarized ones?

These questions are pretty technical, and I hope someone here is more knowledgeable than me in electronics. My plane is a 1970 M20E, and I attach the schematic of the relevant dimmer circuit. 1) A while ago I replaced the lenses for the 6 indicator lights (gear up/down, hi voltage, vacuum hi/low, boost air) with nicer, new lenses. After this the lights were a bit dim, and the guy making the lenses recommended to me to replace the filament light bulbs with modern LEDs. I did this, and all was great. However, a couple of days ago I flew at night, and noticed to my surprise that even though the gear was up, both the "Gear UP" and "Gear DOWN" lights were on. The green "Gear DOWN" light was less bright, but certainly still clearly on. When I shone a light in the light sensor next to the dimmer switch only the Gear UP light stayed on. My guess is that there is a small residual current going to the Gear UP light, even though the gear is up, and only when the photoresistor is not illuminated. The original incandescent light bulb needed much more power to light up, so it was not visible, but the LED is more sensitive and senses this small current. However, I do not understand how this could be happening based on the circuitry. 2) My second question is more standard. I guess the display on my KX155 is getting old; on this last flight, when it was pitch dark, the display was mostly unreadable. I understand that the issue is that the dimming circuit lowers the voltage to the display to a level where the older display cannot light up. I read that there is a relatively easy adjustment to up the voltage slightly to the display, so that even at its lowest setting it will be readable. Does anyone know how to do this? Or have a link to a tutorial? Thanks!

As others have said, the first thing to try would be to run rich of peak in these temps (maybe 75 degrees ROP?), while also covering some part of the oil cooler with aluminum tape. If this is not enough to get your CHTs, I would get a full engine monitor and see if all my cylinders have the same problem, and proceed from there.

My own experience is simply that many times when ATC points traffic out to me (when using flight following) it takes me a while, and sometimes I never manage to spot it. Even though eye doctors say my vision is 20/20 and there's nothing wrong with my CPU afaik, I know there is a plane there but I can't spot it. I have flown several times with an air traffic controller friend who has very good eyes, and he sees traffic way more often than I do. The moral of this is that *I* feel I need every help I can get; so I use ADS-B-in as much as I can, use flight following religiously, and if any of these suggest there is a target in my direction I deviate as much as practical so as not to get anywhere close to a conflict. For me, ADS-B has been an excellent tool, as it lets me know of potential conflicts. I know it is not perfect and still scan the horizon as much as I can, but for every airplane I find by myself, ADS-B and ATC tell me of at least 10 others. So I think it is great. But I can also understand how others (with better vision, perhaps) could feel that their scan is good enough to keep them safe. I also can't forget an interview with a very experienced GA pilot who, when asked what he is afraid of the most, answered "fire on board and mid-flight collision". I know these are not as likely as many other potentially fatal accident causes, but sometimes people are not 100% logical...

I had a Cherokee 180 for 10 years and then moved to a 1970 M20E. The 180 could haul a bit more, and could be flown to more grass strips than the Mooney. It had better visibility from the cockpit (bigger windows) and felt a bit less cramped in the front (the wheel well for the nose wheel takes up some space between the front seats). The back seats were more useable in the Cherokee, though not by a lot; however, the F and J models suggested will have more room in the back as well. But after a while (took me about 4-5 months to warm up to the Mooney) I love how the Mooney flies and how efficient it is. The Cherokee was barely a 110 kt bird. The Mooney is at 145 kt on about the same amount of fuel. This means the difference between a 4 hour and a 3 hour flight to Madison-Nashville, which I do to visit my son. It also can go much higher, the 180 could barely climb above 11k, I have had the Mooney comfortably above 16k and could have kept climbing; this made a big difference for me in the mountains. But some of my feelings for the Mooney could also be a factor of the accoutrements -- the Mooney has a nice autopilot with altitude hold while the Cherokee had none, WAAS GPS, nice engine monitor... These all make quite a difference. But certainly the Mooney feels more like a traveling machine (albeit sports-car like) than a trainer.

That facebook link takes me to some guy who has not posted anything??? Was that what I was supposed to see?

PM sent

I don't know if this is ok to do in the breaking-in phase, but if this was not an issue I would try a static RPM check on the ground. Good way to see if engine makes full power. The type certificate should say what you should be seeing.

I see, sorry. As others have said, something is seriously wrong -- it should be cruising much faster. My impression was that despite the longer body, Es and Fs were very similar in speed, and I consistently see 145kts in my E without the speed mods you have. I would still do a 3-way run. It's easy: go out on a smooth day, and you fly compass headings going first straight N until the speed completely stabilizes (takes a couple of minutes; refer to the GPS ground speed, not any other speed; this will be the speed you'll record); then turn due E and read the speed after it stabilizes, and finally same thing due S. Record these three speeds and put them in the calculator here: http://www.csgnetwork.com/tasgpscalc.html It will give you your TAS.

Hold on, am I wrong? It seems that at 9500 feet your G5 shows a TAS of 156 kts, which is great!

As I said in an earlier post, I am also affected, and also with an engine rebuilt by Penn Yan (but in 2012, smack in the middle of the bad period). When I called them they were able to tell me the exact date the bushings were shipped from Lycoming to them. So I suspect they should be able to do the same for you.

Oh, so we're not talking about a Mooney? Only the original M20 (no letter) had the O320, and those should be bought only by museums -- they still have the wooden tail I think. Or maybe also some M20A's, with just the wood wing?

What engine are we talking about? Lycoming, Continental? If Lycoming, is it the IO360 (angle valve) or O360? Need more information. As an aside, for airplane engines the heads are integral to the cylinder, so you are talking about pulling the whole cylinder. It would also be very helpful to know how much the engine has been run in the past year. If the engine has sat a long time, and there is no other indication of rust (camshaft, lifters) the compressions could come back up quite a bit after running it for a while on the ground, to clear surface rust. Also, honing the cylinder and re-ringing the piston is not a very expensive affair. 1253 SMOH is not the end of engine life. If it is not making metal you are roughly 2/3 of the way to a new overhaul (2000 hours). Also could depend a lot on who did the overhaul and how much they actually did (but you said you don't know this...)

I already talked to him. His suggestion to talk to this guy in Vegas who has a business trading props yielded nothing, that is where I got the $11.5k quote.

Somehow I got this idea in my head that I should start to look into replacing the prop on my 1970 M20E. I currently have a 3 blade McCauley which is 12 years and about 550 hours old. Runs perfectly, but all my efforts to balance it well did not yield a smooth result. I was hoping to find somehow a good condition B-hub Hartzell two-blade. It does not need to be the newer scimitar, older style blades are fine. The problem is the cost. I was told by a prop shop that I could hope to get about $4k for my prop. But the same shop would only sell me a refurbished prop, and a refurbished B-hub prop will cost $11.5k. I can't justify spending $7.5k only to smooth out a bit of vibration. However, if I could find in a private transaction a good used prop for about $5k, spend another $1-2k for an IRAN, that would be within the price range that would make the proposition attractive. Where can one find listings for such items? I looked on ebay and on barnstormers. Also, here is another interesting question. Does anyone know if older style blades (non-scimitar) can be installed by a prop shop in a hub designed for scimitar blades? Or are they incompatible? How expensive is it to swap blades in a hub?

Yes, SB480F lists as possible sources of bronze the following: Connecting rod bushings Rocker bushings Crankshaft bearings Intake valve guide Piston pin plug Idler gear bushing