Old Engine = Runout Engine ?

[KyleTownsend]

I am in prebuy on a 71 F model. The engines are mid time (700/900), but haven't been overhauled since the late 70's (meaning the plane hasn't flown a whole lot, especially in the past 5 years).

According to Continental, this makes them "run-out" and due for overhaul. I am wondering how much concern you guys would have about the age of the engines, and what you would look for in order to determine their health. Assuming they check out OK, how much value would you put on them in comparison to similar-time engines that had been overhuled in the past 10 years?

At this point, I am having borescope, compression tests, and oil analysis done.

I have already determined that the engines don't have the VAR cranks, and one probably has the narrow pushrods.

Thanks,

Kyle Townsend

[kevin]

Kyle,

You will likely get lots of opinions on this. Here is mine...

If I were to buy such an airplane, I would consider the engines to have core value only, and would reduce the price by the price of two factory remans. "Sitting" (not flying) is the worst thing you can do to the entire airplane (I would expect potential problems with the gear retraction mechanism and the radios for example), and is especially bad for the engines. If the engines pass the tests you describe, and you have throroughly examined the entire airplane for corrosion (I hope you are getting it from Arizona) AND you can buy the airplane very very cheaply, it might be a good deal. But expect to change the engines very soon, and expect thousands of dollars of other problems from the airplane having sat so much.

One thing that might make the airplane a better deal (but the above comments about the engines still apply, you should plan on overhauls in the near future) is if it has flown 100+ hours a year for the last two years. Then maybe some of the above problems will be mitigated by recent maintenance.

Be aware that if the airplane has been sitting for a while, it can pass all of the engine tests you describe, and still easily require major engine maintenance within 50 hours or so.

In general, I would run from such an airplane unless I was an A&P and had some time and money on my hands.

My opinion.

Kevin

[Rickskymaster]

I would like to know how much it flew the last year and who was doing the maintanence.
Be sure to buy this knowing that you most likely will need something go, after the sale.
As the saying goes, buyer beware.
Good luck

[Ernie Martin]

While I don't disagree with the above comments that you should value the plane as if it had runout engines, my own experience suggests you might be pleasantly surprised.

My first Skymaster was a 1969 337D that sat in New Orleans for like five years without being started. And then spent another 10 years with negligible use.

I'm a mechanical/aerospace engineer with a Master's from Caltech, so I was leery about this aircraft. Because all the records had been lost (yep, unused engines and no records) I spoke to the prior owners back to the guy who bought it in New Orleans. He actually saw the airplane land in NO, when a hippie-looking couple walked away saying they'd be back in a couple of days. Three years later the Sheriff sold it at auction (the buzz was that the couple who abandoned it were drug traffickers). The buyer I spoke to bought it from the Sheriff -- grass growing all around it -- with plans to refurbish it to a serviceable condition (the engines were at about midlife, and he found evidence of the overhauls done about 5 years before landing in NO), but it never happened and two years later he sold it to a a dealer who reurbishes abandoned airplanes. Two owners later -- who rarely used it -- and then I bought it for a song.

Because the engines had good compression and low oil consumption/leakage, I decided to run them. And for two years they performed flawlessly, mostly over Bahams waters. When I eventually sold it, the engines were running good.

So, that's my story. Buy it for a song and run them out, that's my advice. And you might be surprised.

Ernie

[KyleTownsend]

Thanks for the advice. FYI, the plane has complete logs, some minor damage history that was properly repaired, really really old radios (basically worthless 360 channel units), original paint and interior in average+ condition, flies good, all gauges, systems, etc. functional. Airframe around 2500 Price 56.5. Bargain or FoolCatcher?

Thanks,

Kyle

[WebMaster]

my suggestion would be that it is reasonably fair price. Realize that radios will have to be replaced soon, and engines probably in the first year of operation.

As a suggestion, you might get a quote from an avionics shop to upgrade the radios, and presuming you are not paying cash, roll it into the note. Lessens the initial sting.

[skymaster]

my 73 p was 3-4 years sitting. the props were 2 hrs soh . But they were scrap. water got into bearings. i traded hard on the engines. suprisingly the engines were ok. but the props were expensive garbage. J

[kevin]

Oh no Kyle, I completely disagree with Larry (sorry Larry). I think 56K is a "fool catcher" price, to use your words.

A mid-time 71 337F books at 66,500 to start with. Subtract half the cost of mid-time engines, plus the labor to put them in, and overhaul the associated accessories, I compute that to be 20K to start with (40K to replace 2 normally aspirated engines with remans and overhaul the accessories, plus labor, is normal, maybe even low). Assuming just a minimal IFR stack that needs to be fairly quickly replaced, you are talking a 15K including labor, and that is *minimal*, most folks spend 20K or more. Unfortunately, resale value on that stack is only about 10K over what you have now, (i.e. folks will pay about 10K more for an airplane with "acceptable" radios vs one with crap radios, although a few will pay more for really cool new radios), so you should subtract another 10K for the radios. Damage history makes an airplane harder to sell, and lowers the value, although finding an airplane without damage history is becoming a little more difficult, but I would expect a 10% to 15% hit to the value of the airplane, and as I said, when you go to sell it, you will wait much longer for a buyer if you have damage history. (Note: I am NOT saying that necessarily makes sense, a properly repaired airplane, emphasis on the *properly* should not be of significantly lesser value, but the market does not seem to agree with this).

So, just on numbers, start with retail book of 66.5K. Nobody pays retail book for non-creampuff airplanes, so I would knock it down to 60K immediately, but that is a matter of opinion. Now subtract:

6K for damage history (this probably should be more)
20K for engines
10K for avionics

I get a book value of 24K. But the airplane has been sitting for a long time, and that reduces the value further, although there are no hard and fast rules for how much. (I am not talking about the engines now, I am talking about the effect of sitting on hoses, seals, corrossion in the airframe and electrical system, on an on.) The way I would think about this is the following.

When you buy a new airplane (to you), the first annual is always a bitch. Your mechanic may not agree with the previous mechanic on one thing or another, he will research and check ADs more carefully on the first annual, and because the airplane is new to him, he will inspect it more carefully and see things the other guy just plain missed. So, with average shop rates, you can figure that the first annual on a 337 is going to be 8K to 10K (not owner assisted). After the first, your annuals should go down to 4K or so in good years. BUT, if the airplane has been sitting, I would expect at least an additional 5K in maintenance (in addition to the engines, which you will likely replace) and it could be more, over the first year. So let me do a comparison.

My figures, book value is 24K. Let's say you pay this for the airplane. At the end of the first year, you have spent:

24K for the airplane
5K for the extra maintenance for the year
20K to replace ONE engine (you "get away" with the other)
15K for the radio stack

You now have a good airplane, with nice radios and one runout engine. You have paid 74K for this plane, and you must replace the other engine soon probably. You can resell it, however, for only about 60K because the runout engine subtracts 10K and the new radios add 10K (6K reduced for damage history). So you are 6K backwards in the airplane as long as that engine lasts, and when it goes, you are 16K backwards in the airplane. *And that is if you pay 24K for it.* Imagine where you will be if you pay 56K.

Now, lets say you go find a mid-time, no damage history 71 337F with King radios, like KX155 era that has been flying 100+hours per year, so the engines are only 6 or 7 years old. You can buy that airplane for book 66K (proably 50K in this market), and just go fly it. You have risk on both engines (not everything makes TBO, true of all airplanes), but the regular flying means the risk is lower and you pay 5K less in maintenance the first year and you don't have to wait out 2 months of downtime while the annual is done, an engine is changed and the radios are replaced. If something changes in your life, you can sell the airplane for pretty much what you paid for it.

I think just buying a good airplane, rather than a distressed one, is worth the reduced aggravation. But if you do buy a distressed airplane, make sure you REALLY buy it VERY cheap (for a "song" as Ernie recommended), or you will end up sad later.

I have seen people buy distressed Skymasters over and over again, and sell the airplane two years later complaining that "those 337s are really high maintenance". But the fault was not of the airplane, it was the owner buying an airplane that had been undermaintained and underflown for years (like the one you are describing) and the piper needed to be paid.

Others may quibble with the figures in this message, a few K either way. But my point I think will stay intact. Do I think the owner of the airplane will sell it to you for 24K? Probably not. Maybe Don can chime in here with what the salvage value of a 337 is, I think it is about 20K, but I have no real data. You are buying a flyable airplane, and that is worth something. If you want to buy a project, and have an airplane that you have thoroughly gone through (either paid to do, or you are an A&P or have skills and A&P supervision) I can imagine people paying 30K, maybe in even 40K for such an airplane. But not more than that. And, as you can derive from this message, I would not be one of them.

The above is a distillation of what I have learned, sometimes painfully, in owning 9 airplanes over 30 years. It is my opinion only, and you should make your own decision about whether to purchase the airplane, obviously.

I want you to be a happy Skymaster owner, and that is my motivation for writing this message. I hope it helps you.

Kevin

[Ernie Martin]

I agree with Kevin's philosophy, but not the numbers. Let's assume you do a thorough check of engines and props, that you confirm that the damage repairs were done well, and finally that the aircraft is airworthy (with a valid annual and all AD's done). My number then is around $45K.

Here's how I got there. First, I read the Vref used prices as a fair number with "basic" eqpt, and I'll only add deduct $5K for the radios. Second, I'm buying this aircraft to fly it and enjoy it, not to sell it, so I'm not too concerned with perhaps losing a little many years from now because of the damage history (and hopefully the then-buyer will do the same thorough check of the repair and I won't lose anything). Finally, I'll deduct $15K for the engine(s).

You say it flies good. With all ADs done and a thorough check of the engines, props and the damage repair, a $45K price seems fair and a very inexpensive way to get into a Skymaster. Of course, you need to reduce the $45K for anything you find in the pre-buy, things like corrosion or ADs.

Good luck.

Ernie

[KyleTownsend]

You guys make some great points. As you might imagine, I have "buying fever" now, but hope to avioid "buyers remorse" later.

I booked the plane out using the trade-a-plane valuator thing. I used average for airframe, interior, and exterior, and indicated a "moderate" damage event and a "minor" damage event based on the descriptions of what constituted these events. Including the existing avionics, and leaving out any non-functional items, the plane booked at $69,000 (making no allowance for the age of the engines).

If I put in 1500 hours for both engines (run out), then it indicates a value of $53,000.

If I put in 0/0 SFRM, I get $93,000.

So, I suppose I was looking at it like buying a run out plane, and paying $3,500 for a roll of the dice on whether one or both engines would last a little while.

Of course, this is problematic to the extent that due to the age of the engines, they don't have the VAR crank (and may not have the heavy cases, I am in process of determining). This being the case, the core value would be anywhere from $3,000 to $6,000 less per engine. So, this means that my roll of the dice would be more in the range of $9,500 to $15,500. That is why I am VERY interested in assessing the engine health before making any final decision.

Hmmm. Decisions, decisions.

PS: On the radios, I could slip two of the mitchell drop in replacements in for $1,500 each and have nice new digital radios.

[KyleTownsend]

On the other hand, If I look at the value with 0/0 SFRM engines ($93,000) then look what it would cost to put the plane in that condition ($48,000), I come exactly to the $45,000 number previously mentioned for the current value. I feel confident that this would be a very "Safe" price to pay.

Of course, it doesn't seem fair or reasonable to assign no value to the engines, since there is some probability that I could run them for another 700 hours. If I through in $75 an hour for this "possibility" then I could see adding around $5,000 and paying $50.

I doubt I can get it for this, but that is probably what makes the most sense.

ciao,

Kyle

[rick bell]

i purchased my 73 p337 in 95 it had only 750hrs tt. both engs. made tbo. used oil and usally ran a little hot, think they would have gone for a few more 100's hrs. so you never know, there are a lot of different experiences and different results. yous pays your monies, yous gets a ticket to ride, its garanteeeeed, until it breaks. same with new, rebuild or used, there ain't no refunds.

[hewilson]

I have a similar question on this topic for you guys.

I am taking a look at a 336 with low TTAF, only 1670 hrs. The engines are original with a "top overhaul" 330 hrs ago. I have not yet seen the logs for myself but the seller claims it has always been flown on a light but fairly regular schedule. He claims the compressions are good and there is no metal in the oil.

My question is, should I consider these as run out engines? Given the TOH, the compressions and the lack of oil, how much additional time could one expect to safely use those engines?

Given that the engines are origianl, I would need to replace both cranks at O/H or reman so I imagine doing both engines would be in the $60K range. Is that a reasonable rough estimate?

Thanks in advance for any input.

I am planning to be in OKC but probably not with my own Skymaster yet at that point. I'll probably come in commercial. But it will be a great chance to see some Skymasters up close.

Hugh

[WebMaster]

You need to check engine prices at airpower, but I think they run about 20K, each. Add 5K for hoses, install, etc, you are looking at $50K to replace both engines.

The next area of concern is props, and only a close inspection will determine if they are still workable.

After that, you are good to go except for avionics issues and gremlins. Look forward to seeing you in OKC, PWA.

[kevin]

As you can see from the rest of this thread, there are a lot of opinions, but I'll start. I would consider them run out. The top overhaul was just a way to get some more life out of engines. If I read your post correctly, the engines on this airplane are currently nearly 40 years old, and have 1670 hours on them (TBO is 1400 I think). These engines are run out, and if you run them longer, you risk catastrophic failure, which, besides making a flight considerably more interesting and potentially life threatening, also increases your cost, even for a reman. So in my view, there are no safe hours left.

Previously in this thread, I said I thought you could replace two normally aspirated. My information is out of date. A reman IO-360-C from Air Power (the $300 over invoice folks) is just under $25K today. I would add three to five thousand to that for labor and accessory overhaul, including the prop. So I think you $60K figure is accurate, and my figure from previously in this thread is way wrong. Since you have old cranks, a reman is probably the only economical way to go. If you the engine was newer, you could of course get a somewhat cheaper overhaul, although I am a "reman" guy, and don't have any experience with other overhaul sources.

My opinion only, you should of course make your own decision based on all the information you collect and your own judgement.

Kevin