Vance Harral

The nuts in question go on the studs that attach the propeller to the crankshaft. If you believe in "Jesus nuts", these would qualify. They're much larger than the ones you see on fuel caps, control linkages, etc. The part number is a specific Hartzell part, not a generic. Spruce doesn't list the A2069, but Skygeek has 'em at $8.29 plus shipping. They have the A-867 split keeper listed at $63.75, which is actually more expensive than the prop shop charged. I don't really see any evidence of gouging here.

Robert, as explained earlier in the thread, the only prop shop in the state (at the time) declined to do an IRAN. Our options were to ship the prop out of state for an IRAN or do an overhaul locally, and we chose the latter. The exact reason(s) the local shop won't IRAN a prop past calendar TBO aren't clear to me, but it's their business, their choice. They've been around for decades, and their policy doesn't seem to be hurting their business.

Thanks for the info, Cody. Our bill is mostly labor, which I'm sure is dramatically higher than an IRAN/reseal due to all the mandatory operations that go with an overhaul, especially blade reprofiling. The shop didn't break out the labor per hour, but I'd guess here in the Denver Metro area, the going retail rate is around $85/hour. That would make for about 24 hours of labor on the full overhaul job, three full man-days. Again, that hourly rate is just a guess, though.

My method for an airport at 5000' MSL where DA approaches 8000' in the summer: advance throttle to 2000 RPM during the runup as normal, lean for peak RPM, then nudge the mixture forward a half inch or so from there. On the takeoff roll I might make a quick adjustment based on EGTs, but I don't devote a lot of time or attention to it. If that sounds imprecise, it is. It should be. If the difference between clearing the trees or not is a few tenths of a GPH in your mixture setting, you made a serious judgement error attempting to take off in the first place.

The $2500 quote included parts, but was "approximate". I never had any illusion the final bill would be that number exactly, nor that there was any chance at all it would be less. Attached is a copy of the invoice wither personal info removed. $742.10 parts, $1980 labor. Big-ticket items in the parts list include new mounting studs and nuts, bearings, and something called a "split keeper". I'm not a propeller expert, and not in a position to quibble over whether every single part in the list is legally required to be replaced per the Hartzell overhaul manual. Happy for everyone here to discuss the bill, but opinions that some parts might not have had to be replaced, or that the labor rate was expensive, aren't going to make me question the decision.

Reporting back here as promised. Reinstalled our prop today after full overhaul. Looks great, worked fine on the test flight, and no drama with the shop. But a little over $2700 all in on the final bill - about 10% more expensive than quoted. Seems to match up with Cody's main complaint about shops running up cost on parts. I spoke with the technician about our blade margins after reshaping. He said after this overhaul, which is the second on the blades, they have about a half inch of margin remaining on the chord, and about 50 thousandths of margin remaining on thickness. His opinion was the blades will almost certainly tolerate another overhaul, and if it doesn't get too dinged up in the field, would likely pass even another overhaul after that. So it seems our particular Hartzell prop is good for about 3-4 iterations of blade work from a responsible shop. That's 24 years of service life even if you reprofile on the extremely conservative 6-year schedule, and only get 3 iterations of blade work. Much longer on our 10-ish year overhaul schedule - essentially a lifetime. I'm still a fan of IRAN/reseal instead of overhaul where practical, by the way. But I don't think a full overhaul is a huge mistake/risk, if you're working with a reputable shop. Might be the most practical option in some cases.

12 years and counting is really impressive, Marauder, I thought we were doing great at 7. But with an RG-35a running $300, our amortized cost over the 7 years was only $43/year. Pretty cheap on the AMU scale, and avoids having another gizmo associated with maintaining the airplane. I'm sure once you get over the hump of the initial wiring, it's trivial to plug in a Battery Minder when you leave the hangar. I don't mean to imply it's a lot of trouble, and I'm not really arguing against their use - I understand why they're beneficial. I just think some owners get the idea via forum lore that our batteries are more fragile than they really are. Trying to provide a real-world data point from the other side.

For what it's worth, our '76F frequently goes a couple of weeks between flights, and has for over a decade. We've never bothered with a battery charger, and haven't had any trouble. No failed starts, no short battery life (last battery went 7 years). The airplane does have an analog clock that runs all the time, so there's always a small load, but that doesn't seem to be an issue. Climate-wise, we have low humidity here, but it frequently gets over 90 in the summer and well below freezing in the winter. The airplane lives in a hangar, but not an insulated one. I confess I don't understand the fascination with Battery Minder and similar products for people who fly at least once a month. I can see it being helpful if an airplane is going to sit for several months. But I just don't think a healthy battery needs help holding a charge for a couple of weeks, in any reasonable climate. For what it's worth, we've run Concorde batteries for many years, which have a stellar reputation. But even the old Gill held up fine for weeks at a time. Not trying to denigrate anyone's good experience with the Battery Minder. I completely understand every situation is different, and maybe we're just a tad lucky. But I'd suggest skipping the cost and wiring of a Battery Minder until/unless you've had an actual weak start.

Makes sense to me, glad you have that shop as a nearby option. Good luck with your choice. I'll try to remember to report back here when our work at RMP is complete.

$1800 does seem like a remarkably good price for a full overhaul. If you feel comfortable with the shop and want (or will accept) the blade work that goes with a full overhaul, I'd take that deal. You might ask them how they manage to do it for so much less than other shops, though. The shop we're using is Rocky Mountain Propeller. They have a video explaining how they overhaul props (see link below). Maybe you can compare what you see in that video with the tools and facilities available at the $1800 shop.

Yes, there's always a chance a shop can $crew you. All you can do is ask for opinions and research reputation, and balance that against the convenience and (limited) control you have with a local shop. Best as I can tell, the only complaint about the shop we're using is they don't do IRANs past the manufacturer's TBO recommendations. Other than that, plenty of good reports, and no stories about destroying hubs or blades without prior discussion.

From the other side of the coin... we just delivered our prop on Monday to a local shop for an overhaul. Pretty much the exact symptoms you're seeing: 10 years since last overhaul (got a new hub at the time on the Hartzell half-price deal), throwing a little grease. In our case we also have numerous nicks filed out over the years, which are a bit ugly though I'm sure only cosmetic. Why an overhaul instead of IRAN? Almost entirely because the number of prop shops in Colorado had dwindled to one when we made the decision - though a second has just recently (re)opened. We wanted a local shop, and as in your case, the shop won't do an IRAN on a 10-years-since-last-overhaul prop. Why is anyone's guess. Maybe liability, maybe lack of interest in dealing with economy-minded customers, or maybe what they legitimately believe to be safety reasons. The point is, our options were to overhaul locally or ship the prop out of state for IRAN. We chose the former. It avoids shipping costs and risks. It also means if they call us next week and say there's corrosion, or the blades need to be condemned, or whatever... we can say, "OK, I'm on my way right now to look at it. I want to see the corrosion, blade measurements, etc. They know we're local, and I like to think that helps keep them honest. Not that they couldn't still grind the blades into oblivion if they were incompetent or malicious, but at some point you have to trust a shop based on their reputation, and this particular one has been in business over 30 years. Assuming no issues, the overhaul will run about $2500, which is more expensive than some of the quotes I'm seeing here. But we have money in the partnership kitty for stuff like this. Even if it were 100% out of pocket, it's not so bad divided by 4 partners. If there are issues, we'll deal with them then. I'll report back here on Mooneyspace if anything interesting comes of it.

I'm interested.

As everyone notes, cabin width, length, and height numbers are comparable or better to the competition. But there are some things that legitimately make the cabin feel smaller to a lot of people. First, the Mooney fuselage is rounded at the top, unlike the square roof of Brand C and the less-rounded roof of other brands. This gives at least the feel and in some cases the actual reality of impingement on the shoulders and heads of tall guys, despite cabin width at the hips and elbows being comparable to the competition. Second, the seating is low with your legs stretched out further, whereas other brands tend to have higher seats and a more upright seating position. Some people really like the "sports car" seating design in the Mooney, but not everyone. I'd be 100% OK with it if it weren't for the way my calf and knee rub on the nose wheel well, which is a minor annoyance I don't get in other airplanes. Finally, and IMO most significant, with the seat positioned to reach the rudder pedals, the instrument panel is closer to you than other brands. I like the way this makes even instruments on the far side of the panel easily visible. But I can understand why a close instrument panel feels "cramped" to some, especially if they're the type to worry about banging their head on the panel in an accident. Whether you're affected by any of the above or not, I think we can agree cabin comfort is a personal thing that varies a lot among individuals. People who have only heard about "cramped" Mooneys without sitting in them are often pleasantly surprised, but complaints from people who've actually climbed in and made their own judgment shouldn't be dismissed.

That's a good question, and I'm sorry to say I don't know the answer. I'm fixated on the IO-360 series since that's what's in my airplane, and forgot C and G models are carbureted. The service instruction relates to detonation margin, which perhaps is only a concern in the 200hp IO-360s in the E/F/J.

There is a Lycoming Service Instruction which recommends changing the timing on the Lycoming IO-360 series from 25 BTDC to 20 BTDC. There's a lot of debate about whether it's a good idea to follow the service instruction. That's up to you. But the most likely explanation for your timing being "significantly off" is that it was deliberately set for 20 BTDC the last time it was adjusted.

Just make sure you actually use the "backup" switch from time to time. If you don't, the contacts tend to oxidize, such that the backup will fail you when you really need it. Some folks argue a single DPST switch is a better solution than two SPST switches for exactly this reason: both sets of contacts are exercised every time the switch lever is operated. It's a good theory, but you're unlikely to notice when/if one set of contacts goes. That effectively puts you back to having a single SPST switch.

All switches designed for high current and/or inductance are spring-loaded, whether they're relays or hand-operated switches. The typical non-relay avionics master switch has the same "quick" open/close behavior as an avionics master relay.

Careful, not all avionics master switch installations use relays. In older airplanes, sometimes an avionics shop will simply wire a large, high-current switch (or two) directly between the main bus and the avionics bus. There are pros and cons to this approach vs. using a relay. I won't get into that debate right now, but if you're debugging an avionics master issue, you really need to get behind the panel and see what the switch is connected to. There may or may not be a relay.

That looks like a backup avionics master switch, given that it's immediately adjacent to the regular avionics master. The idea is that two switches are wired in parallel, and either one can enable the avionics bus. If one switch fails, the other one may be used to keep the power on. Typically used in an installation where a high-current switch directly connects power to the avionics bus (as opposed to systems where the avionics master is a low-current device that controls a relay).

I find a hacksaw works best for cutting the paper element out of the housing: quick, easy, and safe. It does leave "fuzz" at the cut, which I guess you could argue is a distraction when looking for foreign material, but I don't think it's a major issue.

In our F model, the MP gain from opening the ram air vs. closed with a Brackett filter is even less than that. I can see the gauge move a smidge, but not a full inch. And some of that benefit isn't even from filter vs. no filter. The ram-air-open path goes efficiently straight into the intake (hence the "ram" in ram-air), whereas the normal path through the filter requires the air to follow an S-shaped path to the intake. So I'm pretty sure if I just took the Bracket filter off altogether, I'd see 1/2" MP or less vs. having the filter installed. A "better" filter can't improve on that, so not worth the cost IMO. I'm not saying you couldn't win a drag race by a quarter knot in otherwise identical airframes with a K&R filter. But it's not going to get you to a destination any meaningful amount of time faster, nor be the difference in clearing that tree at the end of the runway.

I think there are so many different ways of mounting the microswitch in the various models and years that you just have to look at your particular installation to figure out how it works. In our '76F with the quadrant throttle, we're lucky: the position of the switch can actually be set with a set screw, which is accessible via a hole in the quadrant. Literally a few seconds to tweak it. Someone above mentioned a system where the switch is triggered by actual manifold pressure. I've never seen one like that and would be interested to know how it works. As far as I know, (almost) all installation are just based on throttle position. Note that the exact MAP you get for a given throttle position varies with atmospheric conditions. The nit-picker in me would argue you set the switch for about "N" inches of MAP, not any specific value. If you feel like having a bar argument, try bringing up what "N" should be in the context of an airplane that makes landings everywhere from Dutch Harbor in January to Leadville in August.

Ugh, tell me about it. We have a Garmin 396 strapped to the yoke whose sole purpose at this point is to provide audio terrain warnings. It was cool when new, but at this point everything it can do is better handled through hardware in the panel or on an iPad. I'd just as soon get it off the yoke and sell it or give it away. But I'm not willing to give up audio terrain warnings, and Big G wants literally *thousands* of dollars to unlock TAWS on our GTN650. :-(

It's worth referencing your parts manual to see what's supposed to be there. Speaking only for the 1976 F model, I used to think the airplane was designed with dozens of different screws, too. Then I looked at the parts manual one year and found almost all of them are spec'd as one of two types: AN526-832R8 or AN526-1032R8 truss head machine screws. The exhaust tunnel panels are oddball (coarse sheet metal screws), and the belly panel where the nose gear doors close have a small number of flush head screws. But even with those additions, that's just four types to cover every cowl, inspection panel, and belly panel screw on the whole airplane. At that year's annual, I looked closely and found every "odd" screw I'd been carefully tracking over the years was actually the wrong screw. In some cases a random screw had been improperly jammed and self-threaded into a tinnerman plate of a different size than the screw itself. In others, a speed nut that was supposed to capture the screw had been lost, and someone tried to deal with it it by jamming in the next-size-up sheet metal screw with no capture nut. In the case of riveted nut plates, I was fortunately able to clean them up with a tap. For removable and lost nut plates, I replaced them with the actual spec'd parts. It was tedious work - especially working speed nuts into tight spots - but not especially difficult. Now we have a stock of "standard" screws and nut plates in just a few sizes. Minimal hassle, and easy to replace lost or buggered screws. Worth the effort, IMO.