On Condition?

Mooney Fan

Mooney Fan

Cleared for Takeoff
Joined
Sep 17, 2017
Messages
1,026
Location
Indian Mound, TN
Display Name
Display name:
Mooney Fan
My new to me Cherokee 140 has 1640 SMOH in 1972. I've had it since April this year and have put 67 hours on her. Oil changed at 33 and then 34 hours. No metal found, Blackstone analysis SAT. Compressions last annual all above 74/80. Burns 1 qt oil every 17 hours.

The plane will be going to a new shop for its Annual come April. I have had the oil changes done at the shop and plan to stick with them. I asked the IA if he had any concerns with the calendar time SMOH based on the above data points. He mentioned something about 'on condition' and I didn't follow up with the question.. What does that mean? I would think any inspection of the engine regardless of time, and subsequent airworthiness sign off, would be 'on condition'...like there are no obvious signs for concern.

So what exactly is on condition? Can the IA just say the engine needs O/H strictly because it exceeds 12 year calendar years since recommended O/H?

Thanks
 
That's an O320 - low stress, rock solid.

By "on condition," he means you should overhaul it when something indicates the need (oil consumption, reduced pressure, making metal).

Odds are, you have a thousand good hours in the mill.
 
I'm all in with "on condition" maintenance for an airplane that is regularly flown. Pay as you go! Both Conti and Lycoming have twelve-year limits now, ostensibly for belts/seals/hoses/etc. having a finite life. If the plane goes 200 hours a year, that's not so bad. But 50 hours a year would get you a mighty low-time rebuild! At the point, it would depend upon storage conditions whether you could end up with something failing in flight. Still, these things don't seem to blow crank seals or other stuff on a regular basis. Sometimes the drive coupling for accessories (such as the alternator) goes wonky, so that should be inspected and perhaps replaced, but hopefully that's on the annual inspection checklist.
 
Mooney Fan said:
Can the IA just say the engine needs O/H strictly because it exceeds 12 year calendar years since recommended O/H?
Click to expand...
For Part 91 ops... no, based strictly on calendar time. It's just a recommendation. As for "on condition" as stated above. Unfortunately sometimes "on condifion" can very subjective to the person determining the condition and should always be supported/explained with objective points why the engine condition or whatever item needs work.
 
On condition = monitor and wait for an "indicator" to take maintenance action. It doesn't not mean run till failure.
 
charlie said:
The potential gotcha here is the crankshaft AD looking for corrosion in the front bore. Charlie Melot
Click to expand...

What's a new O-320E2D crankshaft run now? Are aftermarket PMA cranks available?
 
charlie said:
The potential gotcha here is the crankshaft AD looking for corrosion in the front bore. Charlie Melot
Click to expand...
Thanks all for the replies. Good stuff. Just sent in another oil sample so hope to have it back next week. So far, she's good and tight

Fortunately, this crankshaft AD is not applicable to my 0-320 E2A 150hp
 
Mooney Fan said:
Fortunately, this crankshaft AD is not applicable to my 0-320 E2A 150hp
Click to expand...

You're right, it is not applicable. But the inner diameter of a 150hp crank will rust the same as it will if it is a 160hp. Piper's SB cited in the AD does not discriminate based on horsepower like the FAA AD does.
 
mondtster said:
You're right, it is not applicable. But the inner diameter of a 150hp crank will rust the same as it will if it is a 160hp. Piper's SB cited in the AD does not discriminate based on horsepower like the FAA AD does.
Click to expand...
Thanks mondster. I have read a little about this SB and how AOPA and EAA engaged the FAA to have them tailor the Textron SB stating ALL 0-320's to only those 160/hp. Looking deeper for the logic they used for exempting the 150/hp from the AD despite Textron's inclusion of all 0-320's
 
Mooney Fan said:
Thanks mondster. I have read a little about this SB and how AOPA and EAA engaged the FAA to have them tailor the Textron SB stating ALL 0-320's to only those 160/hp. Looking deeper for the logic they used for exempting the 150/hp from the AD despite Textron's inclusion of all 0-320's
Click to expand...

There are contact names and telephone numbers listed on the AD. If you really want to know more about the story behind it you might consider talking to them. But the simple answer according to the AD is that the only engines that had failures were rated at 160hp or more.
 
You must log in or register to reply here.
Back
Top