what is a lower end overhaul? need some advice

rbridges

rbridges

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rbridges
I've got an idea of what it is. This ad lists 120 SMOH, but then later he says 1650 on 2000 TBO. I guess he did most of the OH but used 5 of the 6 older cylinders. So technically, is it 1650 SMOH? I may be contacting the seller, but I don't want to be an idiot.

Bottom line, is this a 1650 or 120 SMOH engine? I'm thinking it's a 1650. Since I've got your attention, any feedback on the plane/price would also be welcome. I haven't VREFed it, but it looked nice at first glance.

thanks in advance

http://www.aso.com/listings/spec/Vi...l=True&pagingNo=1&searchId=15694353&dealerid=
 
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Because the cylinders were transferred, I'd say he's got 1650 SMOH. Not sure why he didn't just get all the cylinders new or reconditioned.
 
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I would want to see the logbooks. It looks like he "repaired" the engine 122 hours ago. I say repair because what he did couldn't be called an overhaul to reset the TBO. As a WAG, it looks like maybe the engine was making metal and he repaired it as cheaply as possible.

The good news is if you don't care about arbitrary times, the bottom end is the expensive part and being rebuilt should give you lots of life. A cylinder here and there is no big deal. Unless you are using it commercially, the remaining TBO time doesn't matter. The bad news is if he took a shortcut on the engine, what else did he take a shortcut on?
 
Bein's how its an O-470, the bottom should be good for a long time. But even if he'd replaced all six jugs, you can expect a top overhaul before TBO. And mabe even two or three, before it needs another bottom.
 
Bottom end is everything hooked to the crank/cam, you're talking about pulling the engine for that one.

SMOH is SMOH, a recent too overhaul (jugs etc) might make a overhaul less, but it ain't a overhaul.
 
is replacement/overhaul of cylinders required for a bottom end overhaul to be considered a legal overhaul for SMOH purposes? Considering a top overhaul doesn't count for squat, I find the former requirement a contradiction.
 
I'm still scratching my head why you wouldn't address the cylinders at the time of all this work. Maybe it isn't necessary, but IMO, I'd go ahead an reset the clock so the speak.
 
rbridges said:
I'm still scratching my head why you wouldn't address the cylinders at the time of all this work. Maybe it isn't necessary, but IMO, I'd go ahead an reset the clock so the speak.
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Maybe the cylinders were relatively new. Maybe he'd had a top done 200 hours ago. Lots of possibilities (good and bad) for avoiding $6k in cylinder expenses.
 
kyleb said:
Maybe the cylinders were relatively new. Maybe he'd had a top done 200 hours ago. Lots of possibilities (good and bad) for avoiding $6k in cylinder expenses.
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good point. anyway, thanks everyone for the feedback.
 
Velocity173 said:
Because the cylinders were transferred, I'd say he's got 1650 SMOH. Not sure why he didn't just get all the cylinders new or reconditioned.
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Maybe they were ?

One more example of advertising.

you will not know what was done until you see the records.
 
Maybe a prop strike, req teardown, insp and put it all back together again.

I'd ask what exactly was replaced with new parts, and what was kept from the old stuff. Forget about the jugs, they are a wear item, just do IRAN on those.
 
Since the FAA doesn't define the term "lower end overhaul", the scope of the work may be whatever the person who did the work chose to do. Of course, the nature of the work done on whatever items are described in those documents as being "overhauled" has to meet the FAA definition of "overhauled" in 14 CFR 43.2. But you'll have to examine the work orders and/or logbook entries to see exactly what components they did or did not "overhaul".
 
Ron Levy said:
Since the FAA doesn't define the term "lower end overhaul", the scope of the work may be whatever the person who did the work chose to do. Of course, the nature of the work done on whatever items are described in those documents as being "overhauled" has to meet the FAA definition of "overhauled" in 14 CFR 43.2. But you'll have to examine the work orders and/or logbook entries to see exactly what components they did or did not "overhaul".
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The whole thing hinges upon how the engine was returned to service. Until we know that we are only guessing.
 
I would advise any one interested in the return to service entries for engines read this AC and get smart enough to determine if the entry meets the requirements of FAR 43.2 for an overhaul.

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/248e88f9cbd60f9f862572b100634598/$FILE/AC%2043-11_CHG1.pdf

can some one fix the link?
 
rbridges said:
I'm still scratching my head why you wouldn't address the cylinders at the time of all this work. Maybe it isn't necessary, but IMO, I'd go ahead an reset the clock so the speak.
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If I pull the jugs, the valves are clean, rings look good, and everything measures out good, why would I replace these cylinders?:dunno:
 
Tom-D said:
I would advise any one interested in the return to service entries for engines read this AC and get smart enough to determine if the entry meets the requirements of FAR 43.2 for an overhaul.

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/248e88f9cbd60f9f862572b100634598/$FILE/AC%2043-11_CHG1.pdf

can some one fix the link?
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Just click here for AC 43-11 CHG 1 (the current version).
 
"Overhaul" in aviation is a legal term. In such, a Pt 91 aircraft engine never needs an overhaul. Overhaul is though a preferred marketing tool as it has value measured in $$$. Engines can be kept operating within spec for a long time by replacing parts as needed, and never qualify as an overhauled engine.
 
Henning said:
If I pull the jugs, the valves are clean, rings look good, and everything measures out good, why would I replace these cylinders?:dunno:
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You wouldn't. You'd get them overhauled, which should be very cheap if they are that good. With the bottom end needing done and one bad cylinder, it would be worth it to spend the little extra if only for the resale value alone. I see stuff like this all the time coming though our shop. People spending $20-40k on a repair and not going the extra few bucks to reset the clock. One guy spent 20k and didn't even want it painted. :rolleyes2: Things like that will bite you in the end.
 
tyndall said:
You wouldn't. You'd get them overhauled, which should be very cheap if they are that good. With the bottom end needing done and one bad cylinder, it would be worth it to spend the little extra if only for the resale value alone. I see stuff like this all the time coming though our shop. People spending $20-40k on a repair and not going the extra few bucks to reset the clock. One guy spent 20k and didn't even want it painted. :rolleyes2: Things like that will bite you in the end.
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If I am not reselling, where is the value?:dunno: I'm better off saving every penny until the last minute then getting a factory engine for the sale.
 
Engine return to service entry:
Date 1.7.14 engine TT 1700
Disassembled engine, cleaned all parts, routed each repairable part to Aircraft services for rework. reassembled engine using all repaired parts, and replaced the following condemed parts with new parts, engine case, crankshaft, cam, 8 lifters, 8 hydraulic units, all gears and common gaskets seals and hardware. All work preform IAW The overhaul manual.

Is that an overhaul?
 
Tom-D said:
Engine return to service entry:
Date 1.7.14 engine TT 1700
Disassembled engine, cleaned all parts, routed each repairable part to Aircraft services for rework. reassembled engine using all repaired parts, and replaced the following condemed parts with new parts, engine case, crankshaft, cam, 8 lifters, 8 hydraulic units, all gears and common gaskets seals and hardware. All work preform IAW The overhaul manual.

Is that an overhaul?
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Legally, no. The A&P needs to say he completed a major overhaul IAW the manufacturer's overhaul manual. The above write-up indicates IRAN.
 
Tom-D said:
Engine return to service entry:
Date 1.7.14 engine TT 1700
Disassembled engine, cleaned all parts, routed each repairable part to Aircraft services for rework. reassembled engine using all repaired parts, and replaced the following condemed parts with new parts, engine case, crankshaft, cam, 8 lifters, 8 hydraulic units, all gears and common gaskets seals and hardware. All work preform IAW The overhaul manual.

Is that an overhaul?
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Not the way it is written, no.
 
Henning said:
If I am not reselling, where is the value?:dunno: I'm better off saving every penny until the last minute then getting a factory engine for the sale.
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there's the rub, I guess. Maybe the owner wasn't expecting to sell at the time, but now that the plane is for sale, you have an additional 1500 hrs SMOH.
 
Witmo said:
Legally, no. The A&P needs to say he completed a major overhaul IAW the manufacturer's overhaul manual. The above write-up indicates IRAN.
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This is true, what else must the entry say?
 
rbridges said:
there's the rub, I guess. Maybe the owner wasn't expecting to sell at the time, but now that the plane is for sale, you have an additional 1500 hrs SMOH.
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Yep, that is where weighing the extra cost to call a repair an overhaul comes in. It really depends how much the difference in cost is. Consider this though: I have completed everything major on the lower end to call an overhaul 500 hours ago. Now I pull it and disassemble, measuring all the parts still within limits, most of them still 'new' limits. All these parts are reusable with no further cost. Now I do all the little bits and cylinder stuff that I didn't do before and now I have a "0-SMOH" engine instead of 500hr engine for the cost of the extra labor. I don't really incur any great penalty for doing proper repairs and holding off to sale for overhaul, in fact it has a chance to still prove out advantageous even if unplanned.
 
Henning said:
If I pull the jugs, the valves are clean, rings look good, and everything measures out good, why would I replace these cylinders?:dunno:
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So that you can install ECI cyls. then when the inevitable AD comes out, you can put the old ones back on. :D
 
Aren't there certian parts that are mandatory to be replaced at OH regardless of condition?
 
bluerooster said:
Aren't there certian parts that are mandatory to be replaced at OH regardless of condition?
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For Continental, roughly, main and rod bearings, bushings, starter and adapter, alternator, magnetos, fuel system, cylinders, a bunch of bolts, nuts and gaskets. Oh, and a boatload of man-hours to strip it down for inspection and reassembly.

Really, that's all you probably need to upgrade the 500 hour repair to an OH. :rofl:
 
tyndall said:
For Continental, roughly, main and rod bearings, bushings, starter and adapter, alternator, magnetos, fuel system, cylinders, a bunch of bolts, nuts and gaskets. Oh, and a boatload of man-hours to strip it down for inspection and reassembly.

Really, that's all you probably need to upgrade the 500 hour repair to an OH. :rofl:
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Where are the mandatory replacement parts listed?
 
tyndall said:
For Continental, roughly, main and rod bearings, bushings, starter and adapter, alternator, magnetos, fuel system, cylinders, a bunch of bolts, nuts and gaskets. Oh, and a boatload of man-hours to strip it down for inspection and reassembly.

Really, that's all you probably need to upgrade the 500 hour repair to an OH. :rofl:
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Aren't you really happy Service Bulletins are not mandatory for part 91?

http://www.tcmlink.com/pdf2/sb97-6b.pdf
 
rbridges said:
I'm still scratching my head why you wouldn't address the cylinders at the time of all this work. Maybe it isn't necessary, but IMO, I'd go ahead an reset the clock so the speak.
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The owner may have thought spending thousands to change a few words and numbers in the logbook with zero affect on reliability or airworthiness was a silly thing to do.
 
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