Aircraft ad interpretation

Let'sgoflying!

Let'sgoflying!

Touchdown! Greaser!
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Dave Taylor
I am looking at an airplane for sale on TAP and in the ad, the broker has written ("" means copy and pasted)
"Total Time: 1,075 Engine 1 Overhaul Time: 40 SOH"
and in the detailed description;
"1075 hours TTAF, Continental" (model) "40 hours SOH"

I have received a copy of the logs in which the shop involved wrote:
'Tach time 1027.20 Engine sent to Lycon for repairs; installed 6 overhauled cylinders following nosegear collapse while being towed' (This part is from memory and not an exact excerpt).

Am I nitpicking, to challenge his use of the phrase " Engine 1 Overhaul Time: 40 SOH" for this engine?
Is it leaning towards deceitful to say 'the cylinders were overhauled, so let's call it 40 SOH'?
 
40 STOH (Since Top Overhaul) would have been clear and more accurate. I've always thought that "SOH" is just the time since any type of overhaul was performed, which usually requires further investigation to find out what was actually done.
 
Sounds to me like they are trying to pass off a prop strike inspection and some engine repairs as an engine overhaul. You may want to look at what the FAA's definition of an engine overhaul is. I'd bet it is not what a lot of people think of when you say overhaul, and this work may qualify as an overhaul depending on how it was documented.

You're going to have to peruse the logbooks to make a determination on what was actually done.
 
Highlight the good ,ignore the bad,would want a very thorough pre purchase ,to consider that airplane.
 
Mh, why would you replace cylinders for a prop strike inspection ?

This was an engine repair, not a major overhaul.
 
mondtster said:
That cannot be determined by what was written in the original post.

That said, by most people's perceptions of the term overhauled it doesn't appear that it has been. Sellers often claim engines are "overhauled" in cases like this however, hoping they will get some extra money out of the plane. Smart buyers see right through this.
Click to expand...

Read the log book entry the OP posted from memory. Does not come close to overhaul.

Tim
 
tspear said:
Read the log book entry the OP posted from memory. Does not come close to overhaul.

Tim
Click to expand...

That is your perception not the FAA's. That is also what most people believe an overhaul is, including myself.

However, the engine was clearly disassembled, inspected, and repaired as necessary, which is what the FAA definition of an overhaul is. What we don't know is if it was tested per the manufacturer's specifications, which is needed to complete the overhaul.
 
weilke said:
Mh, why would you replace cylinders for a prop strike inspection ? This was an engine repair, not a major overhaul.
Click to expand...

In a case I know all to well, 2 cylinders were found to be bad during the tear down inspection, so I had all four replaced.
 
mondtster said:
That is your perception not the FAA's. That is also what most people believe an overhaul is, including myself.

However, the engine was clearly disassembled, inspected, and repaired as necessary, which is what the FAA definition of an overhaul is. What we don't know is if it was tested per the manufacturer's specifications, which is needed to complete the overhaul.
Click to expand...

If the ad stated STOH, or IRAN, he would be in the clear. SOH = Since Overhaul. Overhaul has regulatory language and meaning.
Further, the engine was not disassembled or cracked. The pistons and cylinders were replaced; that is all. Having dealt with Lycoming and Continental for overhauled engines, versus IRAN, versus a topping, they are supper specific. If they crack the case, they state it. If they just replace the cylinders that is what is stated.

Every owner I have ever discussed this with previously expects an Overhaul to meet the FAA rules.
An IRAN or A Top? That is complete free form; and there is no guidance. So buyer beware.

Tim
 
Dave, just be sure that it is a big bore continental with a long 2-blade prop for proper wakeups at Gaston's :D

Oh, and don't forget the Marty Robins aux audio input.
 
The only thing you can learn from that ad is that you need more information. A smart buyer would require more detailed info regardless of the ad's content.
 
mondtster said:
That is your perception not the FAA's. That is also what most people believe an overhaul is, including myself.

However, the engine was clearly disassembled, inspected, and repaired as necessary, which is what the FAA definition of an overhaul is. What we don't know is if it was tested per the manufacturer's specifications, which is needed to complete the overhaul.
Click to expand...

There is an entire FAA advisory circular on the terminology regarding overhauls.

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/248e88f9cbd60f9f862572b100634598/$FILE/AC 43-11_CHG1.pdf

The manufacturers overhaul manual spells out what work has to be performed during an engine overhaul. The logbook entry will reference which edition of the overhaul manual was used and what ADs./SBs were complied with. It may well be that splitting the case for the inspection and replacing the cylinders was an 'almost overhaul', unless the steps in the OH manual were performed and documented, it was not an overhaul.

Once you have the case split and the shop tells you that the cylinders are shot too, the difference in cost between 'inspection and reassembly + new cylinders' and performing a field overhaul to service limits should be minimal. If someone chose to cheap out on the couple of $$ that it would have taken to get the logbook entry for a major, I would wonder what else he cut corners on.
 
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here is the (ID-redacted) log entry if that helps clarify.
To me, it seems like they are saying in the advert that the engine was OH'd when it was not. log entry.jpg
 
Yeah, that is not even close to an overhaul.
A top maybe, but that has no legal definition.

Tim
 
Let'sgoflying! said:
I am looking at an airplane for sale on TAP and in the ad, the broker has written ("" means copy and pasted)
"Total Time: 1,075 Engine 1 Overhaul Time: 40 SOH"
and in the detailed description;
"1075 hours TTAF, Continental" (model) "40 hours SOH"

I have received a copy of the logs in which the shop involved wrote:
'Tach time 1027.20 Engine sent to Lycon for repairs; installed 6 overhauled cylinders following nosegear collapse while being towed' (This part is from memory and not an exact excerpt).

Am I nitpicking, to challenge his use of the phrase " Engine 1 Overhaul Time: 40 SOH" for this engine?
Is it leaning towards deceitful to say 'the cylinders were overhauled, so let's call it 40 SOH'?
Click to expand...
Put me down for deceitful. I've researched probably about 20 ads in some detail. Not one of them was "not deceitful." But then I tend to look into "really good deals."
 
weilke said:
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/248e88f9cbd60f9f862572b100634598/$FILE/AC 43-11_CHG1.pdf
Click to expand...

Tell me if I have this right; the only difference between a:

New-limits major overhaul of an engine and
a Rebuilt engine is

1- who does it ('any' A+P vs the manufacturer / agency approved by the manufacturer) and
2- the latter may be zero-timed, not the former.

In that link, the only other thing I find different between the two is for rebuilts it says; "However, all parts used must conform to the production drawing tolerances and limits for new parts or be of approved oversized or undersized dimensions for a new engine.” and I wonder if it doesn't apply to both situations anyway.

Thanks
 
Let'sgoflying! said:
here is the (ID-redacted) log entry if that helps clarify.
To me, it seems like they are saying in the advert that the engine was OH'd when it was not. View attachment 56344
Click to expand...

So where's the Lycon work order and/or logbook entry for the work they performed on the engine? You may need to call them to see what was really done.

I'm assuming that log entry was not made by Lycon. It looks like it was made by whomever reinstalled the engine.
 
If there was an overhaul, there should be another entry in the engine log signed by someone at Lycon. Something along the lines of:

This engine was overhauled to service limits according to Continental overhaul manual version X.X.X. All parts inspected and deemed airworthy to return to service. Installed 6 new cylinder assemblies. All FAA ADs and Continental SBs complied with. Engine test-run. Reference enclosed form 334432 for applicable part numbers and acccessory serial numbers.
Engine Model
Serial #
Total TIS:
Work Order:
Date:

Signed:




If you obtain a copy of the work-order, parts list and NDT report, you get the meat and potatoes like how much meat is left on the crank, what parts are original to the engine etc.
 
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Let'sgoflying! said:
Tell me if I have this right; the only difference between a:

New-limits major overhaul of an engine and
a Rebuilt engine is

1- who does it ('any' A+P vs the manufacturer / agency approved by the manufacturer) and
2- the latter may be zero-timed, not the former.

In that link, the only other thing I find different between the two is for rebuilts it says; "However, all parts used must conform to the production drawing tolerances and limits for new parts or be of approved oversized or undersized dimensions for a new engine.” and I wonder if it doesn't apply to both situations anyway.

Thanks
Click to expand...

That is my reading of the AC.
 
In the appraisal world, there is a distinction between overhaul to factory limits, and overhaul (the former mo betta) even when not performed by the factory. Yes, only the factory can zero time an engine.
 
Let'sgoflying! said:
Tell me if I have this right; the only difference between a:

New-limits major overhaul of an engine and
a Rebuilt engine is

1- who does it ('any' A+P vs the manufacturer / agency approved by the manufacturer) and
2- the latter may be zero-timed, not the former.

In that link, the only other thing I find different between the two is for rebuilts it says; "However, all parts used must conform to the production drawing tolerances and limits for new parts or be of approved oversized or undersized dimensions for a new engine.” and I wonder if it doesn't apply to both situations anyway.

Thanks
Click to expand...
For overhaul to new limits you are correct. But few field or MX shops do so. Instead they overhaul to service limits.
So there generally is a difference. How much is up to the buyer to decide.

Tim

Sent from my LG-TP260 using Tapatalk
 
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