Engine overhaul

AuntPeggy

AuntPeggy

Final Approach
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Namaste
We have about 1900 hours on our 180 hp Lycoming. TBO is 2000. C-172M. We figure we will add another 100 hours within a year. Annual is due in May. Penn Yan is offering a special $1500 off if purchased before March. We really don't want to push our annual into the winter, but...
http://www.pennyanaero.com/ said:
172 Model I, K, L, M, N, and P Owners: Exclusive discounted pricing on the immensely popular SuperHawk 180 horsepower STC, Power Flow tuned exhaust systems, and Airwolf Remote mount oil filters. Requst a quote for full details.
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Are there any comments on this engine?
 
Lycoming's offering some good discounts as well. It might be worth looking into, but last I heard there were some good deals including rebuilt for the price of overhaul, etc.

Disclaimer: I have a personal interest in people giving Lycoming money. :)
 
AuntPeggy said:
We have about 1900 hours on our 180 hp Lycoming. TBO is 2000. C-172M. We figure we will add another 100 hours within a year. Annual is due in May. Penn Yan is offering a special $1500 off if purchased before March. We really don't want to push our annual into the winter, but...
Are there any comments on this engine?
Click to expand...

Your engine isn't going to turn into a pumpkin at 2,000 hours. If it's fine now, and you're putting 100 hours/yr on it, you could be just fine for several more years.


Trapper John
 
Thanks, Ted. I didn't know that. We just got a postcard in the mail from Penn Yan a couple of days ago and it set us to thinking about overhauling the engine a little soon.

We were originally planning on trying to push past the TBO by a year, but our mechanic started making funny noises about TBO after our friend died recently with an engine failure -- the engine was past TBO. (We put over 200 hours per year on the engine.)
 
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I gotta go along with John. We do the overhauls on our club planes on condition not hours.

Discuss this with your mechanic, if the engine is in good shape, go to TBO or beyond and schedule the overhaul/replacement (another decision you have to make) at a convenient time of year.

Joe
 
I'd look into the options. I don't think we're sending out postcards to anyone, but I'm pretty sure there are some incentives that we're offering. It is worth giving a call in and seeing as it's worth a few minutes of your time.

As to the TBO or beyond option, that is something you have to decide for yourself. I would say condition is more important than hours, though. I've seen <1000 hour engines that I refuse to fly behind in all but certain conditions, and I've seen >2000 hour engines that I'll happily get in and fly to Iowa.

Regardless, it's a lot of money and you owe it to yourself to look into which option makes the most sense for you both on timing and who you purchase from. I have a good idea of what I'm going to do when it comes time (and no I don't get a company discount - at least nothing worth writing home about), but that's my plane and my dollar.
 
For those who like to run past TBO.....

your betting that the crank/case/cam survives after you see metal in your oil.

Running over TBO is not always free hours.

price the cost of a crankshaft to see what I mean.
 
Tom-D said:
For those who like to run past TBO.....

your betting that the crank/case/cam survives after you see metal in your oil.

Running over TBO is not always free hours.

price the cost of a crankshaft to see what I mean.
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Tom,

I value your opinion and would appreciate a discussion on how you decide when to overhaul.

It seems to me that TBO is a statistical average of some sort that predicts some high percentage of engines will not have problems before this time.

In my opinion (worthless as it may be) we must be vigilant for signs of pending problems which can come well before TBO as well as after.

I see nothing hard about TBO.

Joe
 
Tom-D said:
For those who like to run past TBO.....

your betting that the crank/case/cam survives after you see metal in your oil.

Running over TBO is not always free hours.

price the cost of a crankshaft to see what I mean.
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What Joe said.

Also if you do see metal in your oil is that not an indication of some serious problem that needs to be addressed ASAP?
 
Areeda said:
I see nothing hard about TBO.

Joe
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There's not. Part 135 operators (piston and turbine) can request from the FAA for TBO extensions when they present a program for conditional inspections.

Use the same criteria they use and there is no issue with exceeding factory TBO's.
 
So, if we decided to skip this opportunity, I have 2 more questions:
1) How do we decide that it is time to overhaul the engine? We send in the oil sample and check the filter with every change.
2) Are we likely to get a similar deal then?
 
AuntPeggy said:
So, if we decided to skip this opportunity, I have 2 more questions:
1) How do we decide that it is time to overhaul the engine? We send in the oil sample and check the filter with every change.
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I would really like Tom to help with this. I value his opinion on this subject more than mine.

I would add to the oil samples:

  • Regular borescope inspections
  • Compression checks
  • Engine parameter monitoring. If you see significant changes in oil temperatures, CHT, RPM on takeoff, fuel flow these are signs that things are a changing and it's usually not for the better.
  • Performance, climb rates, cruise speeds.
  • What else? Sounds, vibrations, oil leaks your plane talks to you, listen.
2) Are we likely to get a similar deal then?
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Also is it a good deal to do it early?

Let's say your overhaul and the other "why nots" will come to about $35,000 (just a guess) that's $17.50/hr for 2000 hrs, or about 85 extra hours on this engine.

How is the plane running now? Are you happy with her? Do you expect anything better to come from handing over this big bag of cash?

Joe
 
Areeda said:
I would really like Tom to help with this. I value his opinion on this subject more than mine.

I would add to the oil samples:

  • Regular borescope inspections
  • Compression checks
  • Engine parameter monitoring. If you see significant changes in oil temperatures, CHT, RPM on takeoff, fuel flow these are signs that things are a changing and it's usually not for the better.
  • Performance, climb rates, cruise speeds.
  • What else? Sounds, vibrations, oil leaks your plane talks to you, listen.
Also is it a good deal to do it early?

Let's say your overhaul and the other "why nots" will come to about $35,000 (just a guess) that's $17.50/hr for 2000 hrs, or about 85 extra hours on this engine.

How is the plane running now? Are you happy with her? Do you expect anything better to come from handing over this big bag of cash?

Joe
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Something a friend saw as his engine started to wear that was a bit telling. He had good compressions but he also would get a lot of plug fouling. The rings, once heated sealed, but when cool shrank enough to let oil seep past and the foul the lower plugs.
 
AuntPeggy said:
We have about 1900 hours on our 180 hp Lycoming. TBO is 2000. C-172M. We figure we will add another 100 hours within a year. Annual is due in May. Penn Yan is offering a special $1500 off if purchased before March. We really don't want to push our annual into the winter, but...

http://pennyanaero.com/ said:
172 Model I, K, L, M, N, and P Owners: Exclusive discounted pricing on the immensely popular SuperHawk 180 horsepower STC, Power Flow tuned exhaust systems, and Airwolf Remote mount oil filters. Requst a quote for full details.
Click to expand...

Are there any comments on this engine?
Click to expand...

It looks to me like they're offering a discount on the STC. Since you already have a 180hp engine, why would you want to switch to a Penn Yan STC from whatever STC you already have? IMHO, wait for the engine to tell you it's ready for an overhaul. :yes:
 
IMHO of when to rebuild any engine is a case study of that engine, you need to know history of the engine and the common problems of the type.

no one with any common sense can make a flat statement as to when to overhaul.

You need to know what the owner wants to do, if you are going to just use the old engine as a core for a new engine? I'd run it to failure.

Does the owner want to overhaul their engine on the cheao? I'd not take the chance of loosing the crank or other internal parts that may be rebuildable.

Your engine probably some where in between. Is it a new from the factory first run engine?

Does your engine have ADs that show the crank will be rejected at the time of overhaul?

Is your engine an antique? is there parts available? You sure don't want to loose one of those.

Is your engine a very common type, that you can run to failure and junk and get a used engine to replace it?

There are so many variables, every engine is a case study of its own.
 
Good comments one and all, can't argue with them.

My $.02 worth is if you can afford it now, and can find a real bargan (shops are looking for work to stay busy) this may be the best time to do it. The peace of mind you'll have is worth it IMHO if you are flying 100 - 200 hours a year.


What ever you decide I'm confident it will be the right decision based on sound decision making.


Let us know what you decide so we can criticize it! :rofl::rofl::rofl:
 
Geico266 said:
Let us know what you decide so we can criticize it! :rofl::rofl::rofl:
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Vicarious pleasures from spending other peoples money? I do enjoy it.

Peg it's your plane. The only real criterion is that you are comfortable. Please do not compromise, what matter is that you are safe, nothing else. Like she said, let us know what you decide.

Jow
 
Areeda said:
Vicarious pleasures from spending other peoples money? I do enjoy it.

Peg it's your plane. The only real criterion is that you are comfortable. Please do not compromise, what matter is that you are safe, nothing else. Like she said, let us know what you decide.

Jow
Click to expand...


She? :mad3::mad3::mad3: :nono:


:mad2:


Not that there is anything wrong with that!


:rofl::rofl::rofl:
 
Milk doesn't automatically go bad on the sell by date, just an an engine doesn't automatically go bad at TBO.
 
Geico266 said:
She? :mad3::mad3::mad3: :nono:


:mad2:


Not that there is anything wrong with that!


:rofl::rofl::rofl:
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Whoah, my perception of reality is head-over-heals!! Geico is not a she???

Sorry, I'm flabbergasted. And I apologize!

Joe
 
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Areeda said:
Whoah, my perception of reality is head-over-heals!! Geico is not a she???

Sorry, I'm flabbergasted.

Joe
Click to expand...


I've double checked and asked my wife. I'm officially a "he". For the time being. :rofl:
 
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EdFred said:
Milk doesn't automatically go bad on the sell by date, just an an engine doesn't automatically go bad at TBO.
Click to expand...

Not every engine makes TBO. too

What would you do with a 0-320- that is approaching 3000 hour since last major and the compression is 75 or better on all cylinders, the oil consumption is 15 hours to the qt, the oil pressure is normal, and it makes all the book numbers during run up, and it is not fouling plugs. but, the next time the case is opened for any reason, the crank must be removed from service
 
Tom-D said:
Not every engine makes TBO. too

What would you do with a 0-320- that is approaching 3000 hour since last major and the compression is 75 or better on all cylinders, the oil consumption is 15 hours to the qt, the oil pressure is normal, and it makes all the book numbers during run up, and it is not fouling plugs. but, the next time the case is opened for any reason, the crank must be removed from service
Click to expand...

I've had milk stored correctly, and it hasn't made it until the date either. So like always it depends. In the case of the aforementioned engine, do whatever I can to not open the case....orrrrrrrrrrrr....open the case and not log it. :D
 
flyingcheesehead said:
It looks to me like they're offering a discount on the STC. Since you already have a 180hp engine, why would you want to switch to a Penn Yan STC from whatever STC you already have? IMHO, wait for the engine to tell you it's ready for an overhaul. :yes:
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They have lots of deals. The one I copied is for the STC because it was available for cut-and-paste and I didn't have copy for the regular overhaul.
 
Areeda said:
Vicarious pleasures from spending other peoples money? I do enjoy it.

Peg it's your plane. The only real criterion is that you are comfortable. Please do not compromise, what matter is that you are safe, nothing else. Like she said, let us know what you decide.

Joe
Click to expand...

Fixed it for you.:blowingkisses:
We're real happy with the plane and the engine. Just starting to worry about our own mortality as well at the engine's.
 
EdFred said:
I've had milk stored correctly, and it hasn't made it until the date either. So like always it depends. In the case of the aforementioned engine, do whatever I can to not open the case....orrrrrrrrrrrr....open the case and not log it. :D
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Hubby assists with the annual every year. If he gets his CFI, I guess we will be needing 100 hr inspections.
 
Tom-D said:
Not every engine makes TBO. too

What would you do with a 0-320- that is approaching 3000 hour since last major and the compression is 75 or better on all cylinders, the oil consumption is 15 hours to the qt, the oil pressure is normal, and it makes all the book numbers during run up, and it is not fouling plugs. but, the next time the case is opened for any reason, the crank must be removed from service
Click to expand...

I'd be waiting with a big wrench to bang the knuckles of someone who tried to open the case, if it was my engine and it was running that good.
 
AuntPeggy said:
Hubby assists with the annual every year. If he gets his CFI, I guess we will be needing 100 hr inspections.
Click to expand...

I do 100 hour inspections on the Aztec anyway. So far, we've always found something wrong that we probably wouldn't have wanted to let go another 100 hours. I think it's good practice to do, but on a 172 might be a little different since you have fewer parts (two constant speed props, two fuel injection systems, two fuel pumps, two prop governors, two engines, retractable landing gear...).
 
I too got the Penn Yan materials. The specials they are offering are on the whole family of engines, and a 'special' offer to upgrade my H2AD to a D2J (LOL) etc. The prices are enticing. I have about 500 hrs to TBO, and being the plane is in a flight school, the chances of going beyond TBO are slim to none. The current powerplant has 100hr checks every 2.5-3 months, shows compressions of 76-78-78-77 oil changed every 50hrs, it is clear, no metal and the analysis is fine. It is tending to show roughness in the cold on the left mag runups, but I am leaning it out on taxi and if the left is rough, it burns off after a minute of so on the runup and smoothes out. I know that is a symptom of an 'aging' powerplant, but the plugs are not showing any unusual fouling. Question is, where to go to get the best value for the engine work when the time is here to do the TBO. I figure at the curent usage, I am gonna have to do this within the year.
 
DutchessFlier said:
I have about 500 hrs to TBO, and being the plane is in a flight school, the chances of going beyond TBO are slim to none.
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Why? Tony can tell you about the flight school 172 at Ames that had something like 3600 SMOH. It'd still be flying if a student hadn't plowed it into a snow bank.
 
Rotor&Wing said:
What does doing a 100 hour inspection have to do with the engine at TBO?
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Inspecting the engine more thoroughly more frequently. We don't do compression checks until the annual, now. I don't know whether we do borescope checks at all.
 
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