Run beyond TBO (AKA, I really want this plane)

[SkyHog]

There's always been debates about running engines beyond TBO. I'm curious what y'all think about this one.

This is two part - a poll to determine if you'd run beyond TBO, and a request for what y'all think about a plane that I really want.

The plane:
Price: $21,000
1969 Beech Musketeer. TT 6071, 2110 SMOH, 820 STOH.

Has Dual Nav/Coms Mark 12B with Glideslope, Michel TKM MX300 with VOR Collins Audio Panel, King Transponder

Davtron five function display, Remote ELT, CHT, EGT, Manifold Pressure, Dual Brakes, Dual PTT, 4 place flightcom intercom, Arnav Loran, 60gallon fuel tanks, Vertical Compass Card, New Paint in 1998, original interior

Annual due 02/08

Aircraft is currently flying and flys often.

it is not that far along since Top Overhaul, the engine is not making any metal and the engine compressions are good and healthy. Last compression check showed: 1-74/80, 2-78/80, 3-70/80, 4-71/80

There is no known damage history on this aircraft and all AD's are complied with


The issue, and my guess as to why its so cheap? TBO is 2000. Now, I admit, if the engine quits on me within the first year, it'd be very tough to afford to overhaul it. I personally don't have a problem running an engine past TBO if it is still a solid engine, as I've seen more engines that have quit just after OH than have quit beyond TBO.

So, would you do it? I have attached some pictues.

 

[jesse]

I don't see any pictures attached. Did you talk to the owner yet?

 

[SkyHog]

Yeah, the pics are there now. There was supposed to be a poll too, but I'm in the "penalty box" where the site times out a bunch as punishment. Looks like one of the time outs happened during the posting of the poll.

Yay.

Cool - coming in through a proxy avoids the penalty box.

 

[ScottM]

Have the bottom scoped, look at the oil analysis if available, scope the cylinders and if all looks good go for it. I have seen many an article say there is no reason to NOT go past TBO if everything is good.

Start you engine reserve with a higher dollar amount so that in a couple of years, should you need it, you can rebuild.

 

[infotango]

Some A & P's will refuse to sign an engine off too long beyond TBO.
I think the way to treat an engine that is beyond TBO is as if it owes you nothing, and prepare to replace it at any point.
Our school ran a 172 400-500 hours over TBO and it was running okay until one of the cylinders gave out. Keep in mind that this plane was flying around 6 hours every day, and receiving pretty good maintenance.
IMHO the 18,000 represents the fact that the plane isn't worth a whole lot without an engine, and that this engine is probably not going to be able to be signed off for that much longer, despite the fact that the compressions look okay.

I don't know your financial situation, but I would guess that the cheap price of this airplane is mostly just a teaser, and you could be left with an $18,000 engine less piece of junk if A & P's stop signing it off.

My advice FWIW: focus your efforts on the KR2, and find a good strong engine for that plane.

 

[N7702Y]

One thing to consider is the engine history, and just what was done on that last overhaul. How many hours are actually on key components like the cam and the crank shaft?

I have a friend who had to overhaul an engine (IO-540) due to cam spalling. The engine had only 1,200 hours SMOH. But, it turned out that the cam had not been replaced at that last overhaul and had something over 3,000 hours on it.

That's why I don't like factory remans. Since the factory assigns a new serial number and destroys the old logs, you have no idea just how many hours are on the major components.

On my airplane both engines are coming up on TBO, but I plan to run them until they tell me (via oil usage, compression, etc.) that they are tired. Both were factory new, so I know how old the components are.

Good luck!

Jay

 

[gibbons]

Our Bonanza (1700 TBO) is now at 1980. No oil consumption in 30 hours. Good compression. Nothing in the filter. We're going to keep running it until it starts showing signs of wear... which could be next week. Then again, we know how it's been run for the past 1500 hours. If I were buying one even close to TBO I'd assume the engine was a run-out, and if I couldn't afford to overhaul it I'd pass. That's just me. YMMV.

 

[tonycondon]

i will, and have, flown engines that are past TBO, as long as they run strong. In fact, the most popular airplane on our rental line is past TBO but it seems to have the most power out of any of them. Why change something that works. But Im with chip, if you couldnt swing an overhaul tomorrow then you probably should focus on the KR2

 

[NC Pilot]

I would have no issues with running an engine beyond TBO as long as I know the history of the engine. That is:

1. How the engine was operated.
2. A complete set of oil analysis from new.
3. A complete history of what maintenance was performed on the engine.
4. How often the engine was flown.
5. Look at the crank and camshaft if possible. May require pulling a cylinder to do this.
6. Make sure you have enough money in the bank to overhaul an engine that is beyond TBO. Hint - you can spend as much as the purchase price of this plane to do that.

Also, check the engine mounts - they are probably worn out.

Check with Emon - he has a Musketeer and had to do some serious wing work for it to remain airworthy.

These planes are comfortable, stable and somewhat slow.

Basic engine is good. Plan on replacing the camshaft at overhaul though.

 

[SCCutler]

I'd trust an engine running reliably past TBO more than one which is fresh out of an overhaul.

What does VRef say this is worth?

 

[Dwight B. Van Zanen]

The local FBO routinely runs his rental plane engines with a 2000 TBO out to 3000 hours. He credits the quality of the OH he has done when he finally needs it. They fly a lot. What everyone else said about value of a plane with a run-out engine. But you may also want to know the date the last major and the top was done. If it is not flown a lot, it could be 30+ years since the major, 15 since the top. That should give you pause. Sitting is not very good for an engne. About getting an A&P to sign it off, if they do not have a mechanical reason to refuse you should shop around for another A&P. Making metal? Compression of one jug much below the others? Burning a quart every 2 hour flight? Without some mechanical justification, why would he not sign it off? Seems like an A&P that would refuse to sign off an engine that tests out fine, does not trust his own capability to evaluate if it is airworthy.

 

[TMetzinger]

Hmm... I'm probably confused on this. I know TBO is mandatory for part 135, but I thought it was mandatory for part 91 for-hire ops too? Since there are two anecdotes here about rentals beyond TBO I assume I'm wrong, but I guess I'll try to check the regs.

 

[tonycondon]

i dont think so. part 135 standard op specs include that TBO must be followed. nothing in Part 91 about it.

 

[TMetzinger]

Looking it up, I can't find anything, so I assume what I heard is related to insurability and not FAA regs. I _know_ (because I heard the FBO owner explain to a leaseback owner) that this particular FBO said that they could not operate an airplane with an engine beyond TBO, so it's likely the case their insurer would not provide the liability coverage they wanted if they operated airplanes with engines beyond TBO.

 

[tonycondon]

could be, one of my FBO's major photo contracts requires that the airplanes have engines below TBO. So we keep the best performing airplane for training and rental.

 

[AdamZ]

Nick I think there is a BIG difference between 'Buying' a plane thats past TBO and 'Flying' your plane past TBO. Just my novice opinion.

 

[Dean]

I agree with what Chip said, run it as long as you can, but be ready to OH it tomorrow.

 

[JustinPinnix]

There's always been debates about running engines beyond TBO. I'm curious what y'all think about this one.

This is two part - a poll to determine if you'd run beyond TBO, and a request for what y'all think about a plane that I really want.

The plane:
Price: $21,000
1969 Beech Musketeer. TT 6071, 2110 SMOH, 820 STOH.

Has Dual Nav/Coms Mark 12B with Glideslope, Michel TKM MX300 with VOR Collins Audio Panel, King Transponder

Davtron five function display, Remote ELT, CHT, EGT, Manifold Pressure, Dual Brakes, Dual PTT, 4 place flightcom intercom, Arnav Loran, 60gallon fuel tanks, Vertical Compass Card, New Paint in 1998, original interior

Annual due 02/08

Aircraft is currently flying and flys often.

it is not that far along since Top Overhaul, the engine is not making any metal and the engine compressions are good and healthy. Last compression check showed: 1-74/80, 2-78/80, 3-70/80, 4-71/80

There is no known damage history on this aircraft and all AD's are complied with


The issue, and my guess as to why its so cheap? TBO is 2000. Now, I admit, if the engine quits on me within the first year, it'd be very tough to afford to overhaul it. I personally don't have a problem running an engine past TBO if it is still a solid engine, as I've seen more engines that have quit just after OH than have quit beyond TBO.

So, would you do it? I have attached some pictues.

Nick, that price is certainly attractive. However, my experience owning a plane has taught me that purchase price is a small part of the equation compared to operating costs (especially maintenance). Make sure there isn't another reason the price is so cheap.

FWIW, I got a pretty good deal on my '63 180. However, after a $10K avionics upgrade and a series of $3000+ annuals I began to wonder if maybe I would have been better off paying more up front for a newer plane. Last annual was a breeze and hopefully next month's will be as well.

I would look at it this way. If the plane is $21K as-is, would it still be a good deal if it cost $33K and had a brand-new engine? If the answer is yes, go for it!

 

[etsisk]

Nick, the most fiscally and emotionally dangerous thing in the world is a plane that you know you "really want" ... the safest plane-buying position you can be in is where you can take it or leave it.

You aren't in that "I can take it or leave it" position right now, deep in your heart of hearts, so please recognize that and be very, very careful!!

 

[Michael]

Why not spend the 25K on half my mooney? You know my feelings on buying near TBO.

 

[RotaryWingBob]

I might in an airplane, I definitely would not in a Robinson, because a) I don't consider it safe to fly beyond the 2200 hr overhaul (which basically tears down and rebuilds the helicopter) and b) because a 2200 inspection and overhaul is manditory, most folks don't consider it airworthy (from an FAA viewpoint) over the 2200 hrs...

 

[Tom-D]

6 THOUSAND HOURS ?? your first annual is going to be a killer.... The IAs will pick it apart, the higher the number gets the harder they look.

 

[silver-eagle]

I was told a Warrior could expect to go 3,000-3,500 hours. The mechanic told me as long as the compression was good, keep flying it. In my case, the plane was on leaseback. The school flew it to 10% above TBO (insurance reasons) then I put another 100 on it.
Ask the guys who take care of it. Find out if you'll get a few years out of it before needing an engine. And if you own a plane, how many hours a year would you do? 100 is good. So if you can get 300-400 more hours out of the plane, you'll be ahead.

 

[JasonCT]

Why not spend the 25K on half my mooney? You know my feelings on buying near TBO.

Now that is a great idea
You know the owner and plane, you can log all that complex time, and you would be John's Mooney Brother!

 

[Bill]

so I assume what I heard is related to insurability and not FAA regs.

Our flying club insurance requires us to rebuild at TBO. Our Archer III has 1860TT on it, and the engine runs like a champ, durable as an anvil, yet we'll have to pull the plane from service for a reman very shortly.

 

[Bill]

I would look at it this way. If the plane is $21K as-is, would it still be a good deal if it cost $33K and had a brand-new engine? If the answer is yes, go for it!

I think you're low on the overhaul cost, Nick, is the plane valued correctly if it were selling for $41-45k with a new engine? I haven't looked lately, but last time I did there were plenty of good low time Sundowners available in the mid $40's.

 

[Bill]

Why not spend the 25K on half my mooney?

Can't beat that with a stick! Much more capable aircraft, you know how it's been mx'd, split the fixed costs. Win win, man, DO IT!!!

 

[Bill]

6 THOUSAND HOURS ?? your first annual is going to be a killer.... The IAs will pick it apart, the higher the number gets the harder they look.

Is it just the first, Tom? Just wondering, our club 172 had a $1500 annual last year, has over 11,000TT on her. Interestingly, she's our most reliable bird, NOTHING ever breaks.

 

[Baron 55]

I had a 172 N, 0 320H2AD [TBO 2000] that went solidly to 3450 hr., no new cylinders, no valve troubles, nothing, until we decided to swap for a reman'. I currently have a Cont. IO 470L [TBO 1500] at 1600 hr. running strong. It can happen. That plane there has a bunch of hours on it, but might still be a good enough buy. If I were buying it, I'd want all or a good portion of the overhaul cost in the bank, where it could draw interest for a good while or be there right away if needed. Because...I also had a 172 I bought with about 200 hr. on an engine bought new by the previous owner [not a rebuilt] some years before. It hadn't flown regularly, engine shelled out after I put 140 more hr. on it. [making for a total time of 340 hr. on a 2000 TBO] So.....

 

[Ken Ibold]

it is not that far along since Top Overhaul, the engine is not making any metal and the engine compressions are good and healthy. Last compression check showed: 1-74/80, 2-78/80, 3-70/80, 4-71/80

I would not call 70 and 71 "good and healthy." Those are in the range where they are starting to be suspect. Not a deal killer, but overhaul on this engine is not far away.

 

[Skip Miller]

Have the bottom scoped,

Honest question: What can you learn by scoping the bottom? I would think all you could see is a bunch of (hopefully) oily Con-rods and crank counterweights but not the bearings.

-Skip

 

[gismo]

Honest question: What can you learn by scoping the bottom? I would think all you could see is a bunch of (hopefully) oily Con-rods and crank counterweights but not the bearings.

-Skip

I think he meant check the cam for corrosion, pitting, and spauling. If the engine had counterweights the condition of their pivots would be worth checking too, but I don't think that engine has any. Another spot to check is the inside of the crankshaft at the prop flange if it's hollow.

 

[gismo]

I'd bet that a substantial percentage of the owners on this board are operating engines beyond TBO. Calendar wise that is, IIRC both Lycoming and Continental specify 12 years. How many of you would go beyond the calendar limit if under the hourly TBO?

I ran one engine past 1800 (Hobbs) SMOH before having it OHd at Zepher Engines. That one had just about 12 years on a G&N OH which occured a few prior to my purchase of the plane and it was still running OK although the oil consumption had risen from 1/12 qt/hr to 1/5. The main reason I did the overhaul then was that I didn't want to end up with an unairworthy engine far from home. The other engine was replaced with a reman at 1250 hrs and something like 18 years when we discovered a bad cam and two bad cylinders. The recommended TBO is 1400. The reman now has around 1250 hrs on it and is almost 9 years old. I expect that I'll take it to at least 1800 maybe 2000 if it's in good shape. But in many ways calendar time is at least as important as operating hours.

 

[Skip Miller]

But in many ways calendar time is at least as important as operating hours.

Old Rhinebeck Aerodrome has a 1917 Sopwith Dauphin (sp?) flying with the original 180 HP Hispano-Suiza ("Hisso") engine.

First, I wonder what it means for an engine that old to be "original". How much of it must be original? Cylinders, cranks, cases?

Obviously these aircraft fly in the experimental category. But 90 years old! And we are worried about 12 years? They don't make 'em like they used to!

 

[ScottM]

I think he meant check the cam for corrosion, pitting, and spauling. If the engine had counterweights the condition of their pivots would be worth checking too, but I don't think that engine has any. Another spot to check is the inside of the crankshaft at the prop flange if it's hollow.

Yep. I was just trying to get the bottom looked at without have to break it in half. Because if you do that you might as well rebuild it.

 

[Dwight B. Van Zanen]

I'd bet that a substantial percentage of the owners on this board are operating engines beyond TBO. Calendar wise that is, IIRC both Lycoming and Continental specify 12 years. How many of you would go beyond the calendar limit if under the hourly TBO

Well, the Cherokee I own a share of had 31 years SMOH, 12 years since the top was done, when we did the OH this year. It was running fine, but just starting to make some metal. I commented earlier about finding an AP that uses mechanical reasons for decisions about an engine, not just use hours (or in this case, time since OH). This one flew with no problems about 19 years past the Lycoming recommendations for an OH. But then, it also had a solid crank put in with the first OH.

 

[Tom-D]

Is it just the first, Tom? Just wondering, our club 172 had a $1500 annual last year, has over 11,000TT on her. Interestingly, she's our most reliable bird, NOTHING ever breaks.

Club aircraft usually get inspected by the same IA every year after year, they see the same stuff as airworthy and usually the club aircraft have better care than the private owner will give.

Ca State police had several 182/206, and 185s that that had 25,000 + hours highway patrol on them. and when they sold the state aircraft they brought top dollar, due to their condition, but that is not the rule, more the exception.

The rule is, each aircraft is a case study in its own right. none are the same.

 

[SkyHog]

I wasn't aware that 6,000 hours TTAF was a lot of hours for a plane built in the 60s. I thought that would be a good thing, in that it flew a lot in 40 years.

 

[Dwight B. Van Zanen]

I wasn't aware that 6,000 hours TTAF was a lot of hours for a plane built in the 60s. I thought that would be a good thing, in that it flew a lot in 40 years.

150 hours a year. Not a lot, but enough to keep everything in working order if it was spread out fairly evenly. You would want to know whether it was 5000 in the first 10 years, followed by 20 years in a barn and a partial restoration, and then 10 years of 100 hours a year.

 

[JustinPinnix]

I think you're low on the overhaul cost, Nick, is the plane valued correctly if it were selling for $41-45k with a new engine? I haven't looked lately, but last time I did there were plenty of good low time Sundowners available in the mid $40's.

I was assuming he could get a couple of hundred hours out of the engine before overhaul. IIRC an overhaul is about $15K.