What is O-320 Calendar TBO? (2024)

What's the recommended calender overhaul time on O-320?

As I kick virtual tires to find an airplane for our flying club, I come across several aircraft built in the 70's where it is highly likely the bottom end of the engine is the original one.

Price, P&I, and Panel all fit the search parameters, but as I learn about engines in general, I'm real skeptical when I see a listing for an aircraft from the early to mid-70's with less than 2800 TTAF and no mention of a full engine replacement.

(Sure I know about a full pre-buy and engine scoping and more. But my question is more data gathering about the model and applying that toward any possible purchase negotiation.)

12 years I believe.

http://www.caa.si/fileadmin/user_upload/pageuploads/AD-NOTE/AD-2006/100_sb_SI1009AS.pdf

AggieMike88 said:

What's the recommended calender overhaul time on O-320?

As I kick virtual tires to find an airplane for our flying club, I come across several aircraft built in the 70's where it is highly likely the bottom end of the engine is the original one.

Price, P&I, and Panel all fit the search parameters, but as I learn about engines in general, I'm real skeptical when I see a listing for an aircraft from the early to mid-70's with less than 2800 TTAF and no mention of a full engine replacement.

(Sure I know about a full pre-buy and engine scoping and more. But my question is more data gathering about the model and applying that toward any possible purchase negotiation.)

Click to expand...

So what are you finding? Most haven't been apart for 20 years right and are sitting at 1600 hrs?

That being said, I'd build a spreadsheet with time since overhaul and date since overhaul (or replacement) for the following minimum:

#1. Engine (12 years recommended, which includes most accessories such as carburetor, mags, etc)
#2. Magnetos (500hr or {some have like a 4 year limit also} inspection and overhaul at engine TBO)
#3 Prop - 000 hrs or 72 months (guessing)
#4 Rubber fuel & oil hoses (7 years)
#5 Carburetor
#6 Starter
#7 Oil cooler
#8 each cylinder
#9 Crankshaft
#10 Crankcase
#11 Alternator
#12 Fuel Pump

All of this can be used as leverage. It may **** some owners off but it just true.

hindsight2020 said:

Age is just a number

Click to expand...

Bull

45 year old brake disk from dry county with 1600 hrs on them. Engines are susceptible to the same issues.

hindsight2020 said:

Age is just a number

Click to expand...

Unless you are talking at least 20-25 years age since OH, I would think a guy is a nob if he was attempting to negotiate my price down on a Cherokee because of age of the engine regardless of my flying it weekly.

When I look for an airplane my #1 objective is to get something not out of annual, that flew 100 hrs last year and the last few years. I would rather fly a high hour flight rental then something so low hours and not flown regularly the last few years.

Even still I bought a Cherokee which only flew 24 hrs each of the two years before i bought it and it worked out well for me.

The Comanche flew 200 hrs a year. My theory if its flying they are finding and fixing stuff. If its not then you will find and fix stuff when you begin to fly.

That is just spacing for fast cooling of the breaks. That is an advantage.

bnt83 said:

Bull

45 year old brake disk from dry county with 1600 hrs on them. Engines are susceptible to the same issues.

Click to expand...

bnt83 said:

O-320 160 horse engines are covered under the crankshaft AD 98-02-08 requiring the plug be pulled every X years and checked for corrosion too. I wouldn't accept it without good pics emailed to me or seeing it in person

Click to expand...

It also applies to the 180hp but not the 150 HP so better go that way instead.

I think the Ideal Cherokee would be 150hp 320 or 180hp with Cerminal rebuilt jugs, power flow exhaust, electronic ignition, cruise pitched prop and doubtful to find these but I would love a wow cowl or LFS cowl and fancy pants. Art Mattsion had a cherokee that did 153 mph across a 800 mile round robbin race with a standard engine just changing out a few wing tips, prop mod and cowl.

It would be too expensive to put that on it but if I found one I would like it.