Running Past TBO
 

Have a question for the group: My rear engine is now at TBO. I planned continuing use of it until it no longer meets specs and/or safety

My shop (and they are the best anywhere around, too) mentioned that they are hesitant to sign it off on an annual once it reaches 100 hrs. past TBO. The problem isn't anything except liability. They pointed out that some defense lawyer would have no trouble making them look guilty for signing off on something that the manufacturer felt was safe - i.e. the TBO time. So I can't blame them. No one wants to spend the years it takes to build up a business and then have it gone in one lawsuit due to some freak accident that might occur. And we all know how sick our legal system is and how simple these kinds of things are to bring ruin on anyone/everyone/sans all responsibility.

Well what I'm wondering about is maybe keeping up the maintenance and all as usual, but when annual time comes, finding an IA who will sign it off who doesn't own a shop and have all that risk. Lawyers won't bother to sue when there's no deep pocket (or at least a deep enough one) to recover from.

I don't know just what I'll do but I'm wondering how/if some of the rest of you feel about this or have approached it. At the rate I fly I could - barring something else happening to the engine that required an overhaul sooner - probably get 3-4 years more out of it, give or take how the engine does, etc.

Input and thoughts appreciated.

Annual
 

Paul
The next time you need an annual, send me an E-Mail and maybe you can fly down to Oklahoma (F22) for a couple of days.
Fred N358

Hmmm
 

Paul:

I would take Fred up on his offer next time your due for annual. He's pretty damn good -- it was great to meet him at our OKC fly-in a couple of years ago.

I'm a lawyer that does both plaintiff and defense work, including aviation law. I know of a couple of shops local to me that have a similar view to your shop's. However, it's a business decision which can be convenient to them. Thousands of shops use the prevailing standards for annuals for Part 91 birds and never have a problem.

However, if I had endless resources, I would probably keep my brand new jet, my flight crew, and my personal airport in accordance with commercial Part 135 standards. :)

But to be fair, I believe that you are flying a TSIO which I have heard are a bit more sensitive than us normally aspirated folks.

It would be interesting to see what other, more experienced 337 drivers say about TBO. I have had a couple of engines go well past TBO -- but compared to most of these guys, I'm pretty green.

FWIW

Keven
________
Hydrocodone Rehab Forum

Paul
I had all my maintenance done in Burley, ID at the Flight Doctor. Tim, Kevin and Brian kept up my 337 for 10 or 12 years. They did a great job and my rear engine had almost 2300 hours on it before we changed and installed a factory reman. They had no problem with signing it off because all the numbers were good. It was starting to use a little oil (1 - 2 quarts per 5 or 6 hours) so we decided to make the switch. Although the engine was still running strong. I have heard the same from others about over TBO.


http://www.theflightdoctor.com/

My recent experience says that running a dependable engine past TBO is a he.. of a lot more reliable than buying a new zero time rebuild from Continental.

My previous front engine was removed at a little over 2800 hours (I think it did have a top job during that time).

I wish I had it back... The zero time rebuild I put on the airplane has had two cylinders fail in 305 hours (1 year). Both have sticking exhaust valves.

By the way, Continental isn't exactly jumping through their rear end to solve the problem. I called them and identified the symptoms with the first failed cylinder. Their answer was, remove it and send it to us and we will determine whether there is a problem. I contacted our supplier and they arranged to send a new cylinder and piston. We replaced them and that took care of that cylinder.

Then the second cylinder failed. Our supplier had not returned the first one to Continental at that time. Now they (Continental) want us to send the second one in and they will decide if there is a problem. Our supplier is also sending in the original one.

We have spent several thousand dollars trying to get this "new rebuilt" engine to run right.

I think a few hundred more hours on the old one would have been a lot more reliable and certainly less expensive.

For my dollar... If your engine is meeting specs DON'T REPLACE IT. If I ever get this one settled down, It will be definately showing real signs of wear before I replace it.

To be fair, I replaced the rear engine with a Continental zero time rebuild several years ago. That one has had no problems other than the typical IO-360 oil distribution to the airframe.

tbo
 

IMHO: If your engine passes required compression, and inspection, it's legal, regardless of hours. Run it until it fails compression or oil consumption increases to unbearable, it's far more dependable than a fresh engine. Find somebody else to sign off the annual and let the rest of us know who not to go see.....

TBO
 

Paul, My plane is a P337G 1975. Just had rebuilt engine on front. On the rear engine I had two cylinders changed and it is more than 1,000 hours over TBO. My IA doesen't seem to have a problem since it has good compression and he knows I change the oil no longer than 50 hours and we get analysis of the oil ever one hundred hour. Besides, The Seneca-V has the same engines as I have and I believe their TBO is either 1,800 or 2,000 hours where in the P337G it is only 1,400 hours. Go figure!

Jerry
N34EC

running past tbo
 

In Thursday's "AVFLASH" Mike Busch comments on just your problem. His article appears in AVWEB under "avflash.com" entitled "savvy . . . . ". If you are not already a member, AVFLASH is free (twice weekly) but you have to register.

Also Mike Busch is a regular at Cessna Pilots Assn. He can be contacted there if you are a member. There is an annual fee about $45 but it's worth very penny to belong if you own a Cessna. Mike is THE real expert on Cessna multiengine planes and engines.

Jim

operator
 

the operator can control the tbo event. the accessories will most likely need attention prior to the main event. i would like to see how many hours the bottom will take before failure. it may be a huge anount. anyone have a real number? JCH

I appreciate everyone's input very much, and will watch for any further comments.

Thought I'd add a couple more thoughts:

1 - I really recommend these guys even though they are a little skittish about liabilities. As they said, if a lawyer got one of them on the stand, how would they answer a question like "Why do you think you know better than the manufacturer about the time for overhaul of this engine?" That woudl be that. These days juries (I call them "the 12 stooges" in the chapter of my book that talks about how the jury system has been totally perverted) simply haven't the backbone to make morally-correct rulings when facing an injured person or a widow. But meanwhile I thoroughly recommend these guys even though I may need to get someone else to sign off my annuals for a while.

2 - Yes, the irony about the engines being the same as the Seneca which has the higher TBO has always been interesting.

3 - Yes my engines are TSIOs. So I think I would reasonably expect them to last less time before O/H than normally-aspirated engines, but still I see no reason to do it sooner than is actually necessary if I can avoid it.

4 - When I DO overhaul it, I intend to have it done the same place I had the front engine done when I bought the airplane. They did a great job, have lots of experience, and it has run very well (now into the 600-hour range with no problems ever related to the O/H). I think having a know entity is better than buying someone else's engine. The only wrinkle there is whether or not I have the VAR crank or not.

Enough Already
 

Paul:

Work with me, because I'm trying to pry my sarcastic helmet off during this post. However, I notice that you left "occupation" blank in your biography. Are you an attorney? Are you in the court room frequently?

If not, don't believe everything you hear about lawyers or boogeymen.

Nowadays, prudent businessmen, who, btw, should be formed as a legal and separate entity from their own personal identity, can buy this stuff called "insurance" that protects them from their own screw ups as well as "the 12 stooges." And . . . they can stay in business even after they OR the 12 stooges screw up.

I have found that often, people who lose at trial are upset because they failed to recognize their own errors that they were sued for. 12 disinterested people are usually more likely to recognize a screw up than the person who screwed up. On the same note, 12 disinterested people are also more likely to recognize a greedy plaintiff with a BS claim than the scammer asserting the claim. Juries, for the most part try to get to the bottom of the matter. Yes, our legal system is neither a good, nor perfect system, but it is still the best legal system in the world.

Frankly, in my line of work, I see PLENTY of bad and unethical lawyers. What goes unnoticed, is that I see just as many bad and unethical engineers, developers, builders, pilots, restaurateurs, real estate brokers, business brokers, etc.

FWIW

Keven
________
Drug Testing Kit

the only ethical profession is "agve squeezer" it doesn't pay well; but taste well. so look for my label "ricky lopez"
aged and drank in the same day so guranteeeed not to be spoiled.
rev. al