Time Past TBO on Engine

[kgruskin]

I'm currently shopping for a DA40 and was wondering how many of you out there have gone past the TBO of 2000 hours. If you have gone past the recommended TBO I'd be curious to know by how many hours or how many hours did you make it before you needed to do an overhaul. By needed I mean the engine was telling you it needed to be overhauld.

From what I can tell from the limited information I've been able to find making it to 2400 ETT is easily doable, and can probably go much longer assuming oil samples, compression and everything else remain good during inspections.

Thanks in advance for the information to all those current DA40 owners.

Kyle

[admin]

Kyle,

this is a Lycoming specific question. I have found a few replies to this

http://www.airliners.net/aviation-forum ... ain/87732/

Basically, if compression is good and no metals found... go for it.

[kgruskin]

I'm not worried about running the engine past the TBO recommended number assuming everything looks good as you mentioned. I'm more interested in knowing how many hours others have been able to squeeze out of this engine though.

I agree this is more engine specific but figured others on the board may be willing to share how much time they have been able to get out of their engine before doing an overhaul. Thanks for the link there was some good information in terms of numbers that had been discussed, which pretty much answers my question.

Kyle

[Gasser]

When I was shopping I went to Denton TX to talk to a Diamond service center and they told me it was not unusual to see 3000+ out of these. They had several in a flight school there and they also service several pvt as well.
I expect to see well past my TBO. Time will tell.

[Lance Murray]

If the airplane is on oil analysis, filter inspection, borescope inspection, mid-life (1000hr) inspections, frequent use, frequent oil changes (not more than 50 hour), and frequent compression checks (these should be done on any engine), then I would be confident it is a good engine. Don't worry about the TT and TBO if you are using this for a personal plane. Do these checks and keep on flying until the engine tells you that it is time. TBO is a number placed there to limit the manufacturer's liability in the courts.

[Erik]

If the airplane is on oil analysis, filter inspection, borescope inspection, mid-life (1000hr) inspections, frequent use, frequent oil changes (not more than 50 hour), and frequent compression checks (these should be done on any engine), then I would be confident it is a good engine. Don't worry about the TT and TBO if you are using this for a personal plane. Do these checks and keep on flying until the engine tells you that it is time. TBO is a number placed there to limit the manufacturer's liability in the courts.

I agree completely Lance. This is the on service inspection method of running an engine and I just wanted to add that part 91 allows us to decide if we are happy to keep running our engine as flight worthy, even if it is past TBO. TBO is just a guideline number as far as part 91 is concerned. I wanted to emphasize that it is especially important to keep in mind that some engines might start showing signs of poor health and impending doom well before TBO, as revealed by the above ongoing health monitoring, for whatever reason like lack of us/corrosion, hamfisted use of the red knob and so forth, or even just bad luck. I consider it to be a huge safety necessity that the above progressive monitoring be done as it will more likely than not catch a sickening engine well before it might fail. I would much sooner know on the ground that a 1200hr engine that is supposed to make 2000TBO is ready for OH rather than have it tell me dramatically in the middle of a flight. I would be quite happy running an engine well past TBO if all signs of health are positive.

Here is a nice article on the topic: http://www.avweb.com/news/savvyaviator/187037-1.html

[Tim]

My airplane is at 2086 hours and still has compressions in the high 70s and good oil analysis. I'll probably start using a borescope at the next annual. I think there's more risk with a new engine than with mine at this time.
Tim

[Lance Murray]

Statistically speaking you are correct. The most unreliable engine is a new or newly overhauled engine.

My airplane is at 2086 hours and still has compressions in the high 70s and good oil analysis. I'll probably start using a borescope at the next annual. I think there's more risk with a new engine than with mine at this time.
Tim

[carym]

Statistically speaking you are correct. The most unreliable engine is a new or newly overhauled engine.

My airplane is at 2086 hours and still has compressions in the high 70s and good oil analysis. I'll probably start using a borescope at the next annual. I think there's more risk with a new engine than with mine at this time.
Tim

Based on my experience, I agree. Three of my 4 engine failures in my C310 where in a newly overhauled engine (the first engine failure was not).

[Lance Murray]

4 failures in the same aircraft? Time to change mechanics.

Statistically speaking you are correct. The most unreliable engine is a new or newly overhauled engine.

My airplane is at 2086 hours and still has compressions in the high 70s and good oil analysis. I'll probably start using a borescope at the next annual. I think there's more risk with a new engine than with mine at this time.
Tim

Based on my experience, I agree. Three of my 4 engine failures in my C310 where in a newly overhauled engine (the first engine failure was not).