Log Books and Pre-Buy inspections.

[Tom-D]

When you inspect the log books, what are you looking for?

 

[murphey]

Has it been sitting for extended periods of time, if so why?
Regular annual inspections.
Regular oil changes.
Regular maintenance such as tires, hoses, filters, batteries, etc.
Compliant with all ADs.
And I order the CD from the FAA with all the 337s and such.

 

[Tom-D]

Has it been sitting for extended periods of time, if so why?
Regular annual inspections.
Regular oil changes.
Regular maintenance such as tires, hoses, filters, batteries, etc.
Compliant with all ADs.
And I order the CD from the FAA with all the 337s and such.

Would this entry cause you any concerns?

 

[Apache123]

Would this entry cause you any concerns?

I'd been looking at "salvaged" engines for a potential geronimo upgrade at one point. Even engines with a "significant" prop-strike always had a crank dye-check listed as .002 or .003, .010 seems pretty far up there by comparison. What does this indicate to you (i.e. someone who actually knows what it suggests versus me, someone who is simply amassing information)?

 

[Apache123]

This was one of the sites I checked/referenced, http://www.whiteindustries.com/

So does that .010 mean it had a substantial prop-strike/sudden-stop that would suggest damage-history/accident even if there's nothing else mentioned in the logs?

 

[John221us]

That stuff is over my head, but I did catch a broker who was claiming low hours by ignoring a tach replacement (he didn't fix the ad, even after I called him on it). Also the plane had been sitting two years.

 

[Tom-D]

I'd been looking at "salvaged" engines for a potential geronimo upgrade at one point. Even engines with a "significant" prop-strike always had a crank dye-check listed as .002 or .003, .010 seems pretty far up there by comparison. What does this indicate to you (i.e. someone who actually knows what it suggests versus me, someone who is simply amassing information)?

What you are referring to is the prop flange run out not the size of the re-grind of the bearing journals.

The entry I showed is referring to the size of the bearings.

Any thing else that would cause concern?

 

[Tom-D]

This was one of the sites I checked/referenced, http://www.whiteindustries.com/

So does that .010 mean it had a substantial prop-strike/sudden-stop that would suggest damage-history/accident even if there's nothing else mentioned in the logs?

There are three major concerns with crankshafts, one is the wobble of the prop flange the limit there is usually .005"

The other is the size of the bearing journals, the re-grinds are usual .002" per grind. up to .010" or as we call it M10. which is the dash number of the bearing P/N.

and the crack inspection, usually done by magnaflux method using a fluorescent particle dye and black light.

does the .010" now cause any concerns?

 

[jhausch]

So does this mean it will likely need a new crank at next OH?

 

[Tom-D]

So does this mean it will likely need a new crank at next OH?

That's a very good possibility

try to find one 0-300-A, ( large 8 bolt prop flange) the "D" won't work.

 

[murphey]

Would this entry cause you any concerns?

Nope - it was 25+ years ago. If it hasn't caused any problems since then, why worry?

 

[Tom-D]

Nope - it was 25+ years ago. If it hasn't caused any problems since then, why worry?

Does a 25 year old overhaul with a crank at minimum, worry you?

 

[Skylane81E]

Would this entry cause you any concerns?

Well yeah

 

[poadeleted20]

Would this entry cause you any concerns?

The image appears not to include the entire entry, but the one thing that jumps out is the 27 years since major, which is a very long time, and that would trigger other questions. Also, on any engine overhaul, I'd want to see the full work order detailing everything that was done, and the entry shown doesn't do that.

 

[jhausch]

That's a very good possibility

try to find one 0-300-A, ( large 8 bolt prop flange) the "D" won't work.

Do you think most GA mechanics working would catch this and/or know about the crank "rarity"?

 

[wabower]

The three situations in which I usually examine log books are:

1. Appraisals.
2. Purchaser representation engagements.
3. Searching logs of currently-owned planes for detailed information (time, shop, circumstances, procedure, serial number/ part number, AD, etc.) about a specific situation currently under review.

For consistency, I developed a printed form with the normal headings associated with historical information (date, hours, cycles landings, type of inspection, parts, comments, etc. A very narrow column includes room for one or two ! symbols for noteworthy entries that I may want to find quickly after the review.

I'm interested to see each year's annual usage for the plane, especially for the most-recent 5 years, any significant gaps in the time between annual inspections, the number of shop visits required per year in addition to normal annual, tires, battery, and other expected stuff (i.e. is it a MX hangar queen) as well as the consistency of log entries with other MX records (STC's, 337's etc.)

The process is more time-consuming than I prefer, but scanning the logs requires more time than doing the work manually, especially for older airplanes with voluminous logs. I recently appraised a T-210 with seven airframe logs and a Citation III with five over-stuffed Cescom binders.

After about 3 days the novelty has plumb wore off.

 

[Tom-D]

The image appears not to include the entire entry, but the one thing that jumps out is the 27 years since major, which is a very long time, and that would trigger other questions. Also, on any engine overhaul, I'd want to see the full work order detailing everything that was done, and the entry shown doesn't do that.

The picture shows enough for this thread, I did not want to expose the aircraft ID.

This engine was taken down due to a case thru bolt breaking and the owner was concerned that the case was fretted, and it was. but there was no corrosion or any other age related problems.

Age of the overhaul on a 0-300 continental means nothing.

They simply varnish up and protect themselves.

 

[Tom-D]

Do you think most GA mechanics working would catch this and/or know about the crank "rarity"?

They should, it is very apparent that they take a different prop.

 

[Tom-D]

The image appears not to include the entire entry, but the one thing that jumps out is the 27 years since major, which is a very long time, and that would trigger other questions. Also, on any engine overhaul, I'd want to see the full work order detailing everything that was done, and the entry shown doesn't do that.

IF,,,,, the original owner who had the work completed didn't keep, or ask for the work order, how would you get it ? Is there even a requirement that there must be a work order?

Do you believe that any 27 year old work has any bearing on the material condition of the engine now?

I'd be more interested in what was done to the engine after the overhaul, like cylinder replacement, broken studs that were replaced leaks that were repaired, mags that were replaced, and oil that was used.

 

[Steve Foley]

Age of the overhaul on a 0-300 continental means nothing.

Not according to TELEDYNE CONTINENTAL: See www.tcmlink.com/pdf2/SIL98-9A.pdf

Whether the engine has been operated regularly or has been in storage; gaskets, seals synthetic and natural rubber goods deteriorate over time. Environmental corrosion can occur internally and externally on the engine. This naturally occurring process can inevitably affect continued airworthiness of the engine and engine mounted components and accessories. For these reasons, overhaul the engine at least every twelve (12) years, or on accumulation of the operating hours listed for the engine model.

 

[Bob Noel]

When you inspect the log books, what are you looking for?

One thing I learned to look for is that the serial numbers match.

On my cherokee, I didn't discover that the prop serial number didn't match the logs until I removed the prop to have it re-pitched.

 

[Tom-D]

One thing I learned to look for is that the serial numbers match.

On my cherokee, I didn't discover that the prop serial number didn't match the logs until I removed the prop to have it re-pitched.

It is a nice thing to know that you have the log books for the aircraft you are buying.

 

[Tom-D]

Not according to TELEDYNE CONTINENTAL: See www.tcmlink.com/pdf2/SIL98-9A.pdf

That is covered on a service bulletin which does not apply to part 91 ops, and amounts to a CYA for TCM.

I have never found corrosion to be a problem in 0-300-?

with 1 exception, the sump on the early 172 which have the tall gear set nose down and the water formed in the crankcase will settle in the front compartment and not come out during the oil change,causing the mag casting to corrode.
I have one in the shop now, will post pictures later.

 

[Steve Foley]

That is covered on a service bulletin which does not apply to part 91 ops, and amounts to a CYA for TCM.

You wrote "Age of the overhaul on a 0-300 continental means nothing." If you claim it means nothing when discussing part 91 ops, then the same argument applies to hours TBO.

 

[AdamZ]

Not an A&P and didn't stay in a holidayInn last night but I'd be concerned that no oil was detected if thats what the abbreviation means.

 

[Tom-D]

You wrote "Age of the overhaul on a 0-300 continental means nothing." If you claim it means nothing when discussing part 91 ops, then the same argument applies to hours TBO.

That's true.

The only reason you overhaul any in engine in part 91 is when you no longer trust it for any reason.

the engine on my shop floor at this time is being overhauled because of a prior failure of the crankcase thru bolts and the owner no longer trusted it, but it was running fine. He's overhauling it to save a .010" crank that can be used again with out regrinding which is not allowed beyond .010 under. so in this case we saved the crank which is a 4500-6000 buck item.

 

[Fearless Tower]

If you claim it means nothing when discussing part 91 ops, then the same argument applies to hours TBO.

Which is correct in Pt 91. TBO is not regulatory and many folks run engines (including several on this board) well beyond TBO with favorable results.

 

[Fearless Tower]

The only reason you overhaul any in engine in part 91 is when you no longer trust it for any reason.

Or there is an AD on the engine where the cost and scope of work to comply makes it more cost effective to do a full overhaul at a specified time. The R-985 comes to mind.

 

[Tom-D]

Or there is an AD on the engine where the cost and scope of work to comply makes it more cost effective to do a full overhaul at a specified time. The R-985 comes to mind.

That is also true, cost effectiveness is a big part of the decision to overhaul or repair.

Remember I can replace every part of the engine except the data plate, and call it a repair, and never overhaul the engine, and not have to comply with FAR 43.2

IRAN

 

[wsuffa]

Which is correct in Pt 91. TBO is not regulatory and many folks run engines (including several on this board) well beyond TBO with favorable results.

Unless, for some reason, the TBO is specified as a condition of airworthiness in the type certificate....

 

[wabower]

Snip.
]For these reasons, overhaul the engine at least every twelve (12) years, or on accumulation of the operating hours listed for the engine model.

For appraisal purposes, engines with more than 2x calendar limit are considered as run-out.

 

[Tom-D]

Value is in the eye of the buyer.

Give me a good running older engine and I'll have it rebuilt and do it right and know what I'm flying behind.

If you are buying any aircraft because it has a low timed engine you are buying it for the wrong reason.

 

[jhausch]

Not an A&P and didn't stay in a holidayInn last night but I'd be concerned that no oil was detected if thats what the abbreviation means.

I think that abbreviation is for "non-detergent"

 

[Tom-D]

I think that abbreviation is for "non-detergent"

Many people believe the "D" means detergent.

Detergent... Dispersant ? what's the difference?

 

[jhausch]

Many people believe the "D" means detergent.

Detergent... Dispersant ? what's the difference?

They are spelled differently?...

I'll guess a detergent is wrong because it is designed to make the medium it is in thinner, while a dispersant is designed to either keep gunk in the medium in suspension or help it clump and settle out.

If so, would non-dispersant encourage the gunk to be settle out or stay in suspension? (serious question, I don't know the answer)

 

[Skip Miller]

Detergent keeps the junk in solution. Junk doesn't get caught in the filter.

Dispersant lets the junk coagulate so that it does get caught in the filter, or end up in the bottom of the crank case so it can be drained/flushed out at oil change.

-Skip

 

[Tom-D]

Detergent... Dispersant

which will clean your engine?
Which one will stop coagulation of the oil?
Which one will carry the hard particles to the filter?
which one is not allowed in aviation oils?

 

[RotorAndWing]

Detergent... Dispersant

which will clean your engine?
Which one will stop coowagulation of the oil?
Which one will carry the hard particles to the filter?
which one is not allowed in aviation oils?

coowagulation?????

 

[Tom-D]

coowagulation?????

Stupid auto correct.

 

[weirdjim]

So in an engine that has a good oil filter (instead of the screen) why do we run "aviation" oil instead of some of the really good automotive oils that are on today's market?

Other than the obvious regulatory reasons.

Jim