To overhaul or not, that is the question...

[BKlott]

Just now, KLRDMD said:

What type of engine monitoring did you have and were you doing oil analysis ?

When you look at the description of my power loss events, I think you will realize that neither an engine monitor or oil analysis would have shown early warning. The monitor would clearly show that a problem occurred when it was taking place but it would be too late at that point to do me any good. Admittedly, my experiences could be described as flukes, not likely to occur in the first place or be experienced on a widespread basis. Those flukes can kill you just the same.

I don’t want anyone who flies to mistakenly feel that there is always an early warning to these events...there isn’t...that oil analysis or engine monitors will eliminate the risk(s)...they won’t. They can certainly reduce your risk to some types of events but YOU still need to be prepared anyway, just in case.

An old timer once told me that you will never know how you will respond to an emergency like this until you actually experience it. He said that some guys will freeze in absolute denial. Some guys will pull back on the controls trying to hold the airplane up. (That won’t work.) Some guys will panic. He told me that you have to KNOW that if the engine goes on takeoff that you MUST come forward on the controls to maintain airspeed no matter what you see out the window. That is your only hope.

In my case, I recognized the problem, accepted it and dealt with it the best I could. There was not any time to panic or get scared. After the Mechanic at Kissimmee found the piece of fuel tank sealant, about the size of a booger, that caused our forced landing, fixed the plane and sent us on our way...that was when I was scared. Climbing back into the airplane for that first takeoff after the power loss...that is the one that will get your attention.

 

[Andy95W]

But I think Paul's point would be that neither engine failure would have been prevented by a pre-emptive overhaul. 

Your point is well taken, and good job handling both emergencies.

[RLCarter]

1 hour ago, BKlott said:

The first one was the result of a partial blockage of airflow into the carburetor which caused an immediate power loss and rough running engine due to the resulting “too rich” mixture condition. We managed to get to about 400ft and flew a low, tight pattern back to the runway before it quit all together.

The event at Kissimmee was the result of a small piece of fuel tank sealant that broke off, passed through the two sumps of the right wing, through the fuel strainers and into the carburetor. There it managed to get itself in the perfect position needed to hang up the needle valve, causing the power loss...once again...due to a “too rich” mixture condition. The situation deteriorated quickly as the engine flooded and quit just as we set her down on the cross runway. Awfully glad they had a cross runway there. Not sure we got much higher than 300 ft on that one.

You just cannot count on getting an early warning. My advice would be to think through your options ahead of time...while you’re at home sitting on your sofa. Have a planned course or course(s) of action programmed in your mind of what you will do if it happens to you. Then every time time you pull out on a runway, be ready to respond to any anomaly that occurs. Don’t wait until it happens to start trying to figure out what to do. You will have very little time in an actual event to respond, especially if it occurs on takeoff.

I do think about this EVERY TIME. That, I guess, is the price you pay when you want to keep flying.

 

Neither of those I would count as an Engine Failure

[cliffy]

OK back to our regular scheduled program- engine overhauls-

I did my own 1,000 hrs ago. Here are a few items to bear in mind and . I feel I have as good an engine as you could get by anyone.

Mine actually started coming apart, had aluminum flour in the oil filter.

Items to check on-

7/16 valves as mentioned, get rid of them Get new Lyc cylinders. 

There are two hollow studs that hold the mag idler gears. They came with 1/4-20 bolts to hold them into the rear of the case. That's what failed on mine and wallowed out to 3 times the hole size on one causing the aluminum flour in the oil. There is a S/B to change those to 5/16-18. Do it!

I'm going to presume your engine has complied with the oil pump AD so other than condition that should be taken care of. 

Mine also had a belly roll years before (20) but on magnafluxing the crank we found a small crack in the #1 main bearing journal that would not grind out- new crank. 

I elected for a new cam shaft and lifters.

I had the crankcase gone through by Divco, came back with a good tag. 

I used a new set of Lyc. cylinders The old ones had 3 overhauls on them. 

There is a S/B for the oil pumps that requires a hole to be drilled inside the pump for lubrication. 

Because the idler gear stud wobbled it took out all the rear end gears- all new now. 

You'll need your rods and rocker arms worked on by a good overhaul shop. 

Replace all the parts that OH manual calls for for an overhaul including the Varitherm. 

If you don't have a Lycoming Overhaul Manual, don't even think of doing this yourself. 

I have one and checked each line a paragraph off as it was done. 

Its not rocket science but you must pay attention to details. 

I came out with a new limits bottom end and all new cylinders. Runs like a dream even 1,000 hrs later. 

One last item, if you do it yourself and plan on following the LYCOMING recommended break-in run (as you should legally) by running it in your airplane, UNLESS you have all your engine gauges calibrated before you do you can't count all the engine work as an "overhaul" only as a repair. Calibrated gauges are specifically called out for in Lycomings overhaul manual for the "overhaul run-in" and you have to refer back to the Lycoming overhaul manual as your reference for overhaul when it comes to sign off time. A few A&Ps have been caught on this item by Mother FAA.

Accsssories? Your guess. I did both mags and a new harness, Stayed with my carb. and alternator. Starter was fairly new anyway. 

It can be done and you can get a great engine but its all up to how much work you put into it. 

[Guest]

7 hours ago, jetdriven said:

Whats worth knowing is if this engine has 7/16" or 1/2" valves installed. The smaller has a 1200 TBO and the larger is 2000 hours.  If it has 7/16" exhaust valves, they can snap off around 1200-1300 hours and it gets interesting after that. They are hollow and sodium-filled.  A friend of mine has an exhaust valve snap and it somehow migrated to another cylinder on the opposite side and messed it up, the engine shut down at 800'. She landed, luckily, in a field right below.

The rest of this motor is bulletproof, but 7/16" exhaust valves are not predictable and are a big deal when they break.

The 7/16” exhaust valve is a solid stem and has a shorter TBO. The 1/2” valve is sodium filled and has generally a longer TBO.

Interestingly TCM valves are solid stem and don’t suffer the same failure as Lycoming valves.

Clarence

[bob865]

Thought I would share this in case you've not seen it.  It is a talk given by Mike Busch of Savvy MX.  The opening line is "Engine TBO is a fully discredited concept."  I worked on jets in the Marines and we never overhauled anything.  The only parts that were 'overhauled' were individual components that were IRAN'd and returned as 'overhauled.'  The part I found really interesting was the part describing infant mortality and by overhauling you could be putting yourself at a greater risk of an engine related incident vs. just continuing to run the engine.

Just FWIW.  I still subscribe to the idea that there could be a reasonable time and place to overhaul.  I just don't agree that it corresponds to 2000 hrs.

 

 

[BKlott]

9 hours ago, RLCarter said:

Neither of those I would count as an Engine Failure

The posts were in response to someone who wrote that “...engines don’t just suddenly quit.”

[salty]

16 minutes ago, BKlott said:

The posts were in response to someone who wrote that “...engines don’t just suddenly quit.”

 But the statement was made with overhaul as context. 

[Bob_Belville]

1 hour ago, BKlott said:

The posts were in response to someone who wrote that “...engines don’t just suddenly quit.”

And this reply seems odd. Even if some engine somewhere were to quit suddenly without any notice it would be a very rare exception to the rule which many experts would say is "true". (The exception proves the rule" does not mean that an exception invalidates the veracity of the principle. It means that the exception "tests" the rule.)  

Before you admitted that the proximate causes of your problems, you left us with the impression that the engine just quit when In fact the engine (itself) was not at fault at all and given air and fuel would run just fine.

[cliffy]

To a pilot in command at the moment, when an engine stops operating over a short period of time at 300 or 400 feet it doesn't matter what the cause was- the engine failed. 

Now on later examination, with hindsight being 20/20, if it was found that the components of the engine were OK but that external forces caused the failure "of the engine"  in the context of the flight- the engine still failed to deliver its power.

Granted in terms of this discussion, the engine itself may not have failed the pilot and we can narrow our discussion to parsing words if we must- for this discussion. In the general scheme of things however, if I was the pilot, in general terms, the engine still failed me. This is not a court room. 

Engines don't fail suddenly? I had an IO-320 in a Twinkie swallow a valve with no warning. Sudden failure of an engine. Had it been in the Mooney I would have had to put it in the dirt.

Had a friend lose BOTH engines on a DC-3. One blew a cylinder suddenly with no warning. The other blew the master rod bearing on the same flight while at METO power trying to make an airport. Didn't make it. Went into the desert at night. Both sudden without warning. 

A friend had a crankshaft fracture in half at a rod journal, in a Cessna 140 while in the pattern. Sudden, without warning. The cause was a crank regrind at O/H  by a car machine shop without a radius at the grind juncture causing a high stress fracture prone corner. 

Let me pose another angle on overhauls here. 

How many cars are running around made in 1965 with their same engines still running in them (and not museum pieces)?

How many S/B have come out on the effected engine since it was installed as new?

Now many times has the engine sat unused for months since it was installed and allowed rust to grow inside, over 50 years? 

I sold a brand new IO-360, still in the crate, for friend who bought it 35 years ago. It went straight to overhaul (and it was pickled properly, by the factory when new). 

Nothing lasts forever. Everything has a finite life. 

I think we all would like to see a very detailed tear down inspection report on this engine to validate claims on both sides. 

"What makes you think you know more about this engine than Lycoming does?" A question that has been asked by the FAA a time or two. 

[kpaul]

45 minutes ago, cliffy said:

How many cars are running around made in 1965 with their same engines still running in them (and not museum pieces)?

I own a 1954 Chrysler New Yorker Deluxe with a 331 Hemi.  Runs just fine, has never been overhauled, has sat at times for months without running (it is garaged in Montana).  It leaks a bit of oil, so it is probably time to crack it open and replace the seals.

[FloridaMan]

15 hours ago, BKlott said:

That was not my experience having had two power losses on takeoff back in my Grumman Cheetah days. When the engine quit at Kissimmee one morning, it had nothing to do TBO or whether or not the engine needed to be overhauled. 

These things tend to work right up to the point where they stop working properly. That can be sudden and without warning. Just my luck that it happened twice to me while climbing through about 250 to 300 ft on takeoff.

However, if it makes you feel more comfortable with the notion that you’ll have plenty of warning(s) before it happens to you, please go right on believing that. Those of us who know otherwise from firsthand experience don’t have the luxury of subscribing to such fantasies.

I sincerely hope that it never happens to you!

I had mine quit at 200ft on takeoff as well. I spotted a field and pulled power to make sure it didn't come back and landed in the field. I have an advanced engine monitor and pulled the data after the fact. Nothing could have warned me of the imminent failure which was caused by FOD through the #4 cylinder that decided to introduce itself on initial climb-out. 

[Bryan]

Wonder if you forgo insurance protection if something happens outside of TBO?

[MIm20c]

2 minutes ago, Bryan said:

Wonder if you forgo insurance protection if something happens outside of TBO?

I don’t think this has ever been the case.

The plane I trained in years ago had an engine failure (0-235) that caused it to crash badly two months after I stopped flying it.  It had 100hr inspections and was around 150% of tbo  

There is a HUGE difference between one person/group running the engine carefully and consistently to 150-200% of TBO. It is totally different to buy a plane with 2k hrs and think you can do the same. 

I think the OP made a good decision and I’m sure he will fly more peaceful knowing that things were checked over. 

Funny how everyone tells buyers to plan on an overhaul if anywhere close tbo but it appears that as long as metal chunks aren’t coming out of the exhaust you are gtg. 

[cliffy]

58 minutes ago, kpaul said:

I own a 1954 Chrysler New Yorker Deluxe with a 331 Hemi.  Runs just fine, has never been overhauled, has sat at times for months without running (it is garaged in Montana).  It leaks a bit of oil, so it is probably time to crack it open and replace the seals.

And how many 1954 Chrysler New Yorker Deluxe with a 331 Hemis are there left still running with the original engine?  1?     How many were made?   :-)

[Bartman]

Obviously you can make a case either way, but the original question "to overhaul or not" for this particular engine has already been answered, its going to be rebuilt.  Just because it runs OK and well respected people say its OK to keep on flying does not guarantee it won't fail.  Just because was hatched in 1965 does not mean it needs to be rebuilt.  And just because you rebuild it does not mean it won't fail.

Personally I do not fault the original poster or anyone else for rebuilding a 52 year old engine.  Salty's IA neighbor needs to eat too

[Marauder]

And how many 1954 Chrysler New Yorker Deluxe with a 331 Hemis are there left still running with the original engine?  1?     How many were made?   :-)

In total, there were just 1,100 Town & Country models produced for 1954. Power was from a 331 cubic-inch 'Hemispherical' engine rated at nearly 200 horsepower.

One showed up at auction last year and didn’t sell for the reserve ($50k).



Sent from my iPhone using Tapatalk Pro

[kpaul]

19 minutes ago, cliffy said:

And how many 1954 Chrysler New Yorker Deluxe with a 331 Hemis are there left still running with the original engine?  1?     How many were made?   :-)

In 1954 Chrysler built 2079 New Yorkers.  How many are still running and with their original engine? Probably impossible to know, however I guarantee it is higher than the number of 1954 Mooneys flying with their original non-overhauled engine, even if it is just one.

[rpcc]

my cousin vinny flash back....

[cliffy]

Yes but he drove a Caddy  IIRC

[N601RX]

I had a friend who is an IA help me overhaul my engine a few years ago. A few months later we overhauled his engine as well as another mutual friends engine. All three of them turned out well. In addition to the stuff Cliff mentioned above the other big miss is the lycoming overhaul manual. It is lacking and rather than update it lycoming releases service bulletins and instructions . The only way to get all of these is to buy a subscription to them. There are several hundred of them and you will spend a lot of time looking through them deciding which ones apply to your engine and organize them in a sequence that follows your assembly order. During assembly you will have to repeatly go back and fourth between the overhaul manual and sb/si. Sometimes the manual will tell you to look at a particular sb, other times it does not like they just expect you to know that one exist. Also if you are using pma parts they may have their own sb which may or may not be the same as the lycoming ones. 

[BKlott]

Salty, are you going to pull the engine mount and send it out for inspection? 

 

[salty]

10 minutes ago, BKlott said:

Salty, are you going to pull the engine mount and send it out for inspection? 

 

Wasnt planning on it. I might pull it and repaint it. 

[gsxrpilot]

5 hours ago, cliffy said:

Granted in terms of this discussion, the engine itself may not have failed the pilot and we can narrow our discussion to parsing words if we must- for this discussion. In the general scheme of things however, if I was the pilot, in general terms, the engine still failed me. This is not a court room. 

Engines don't fail suddenly? I had an IO-320 in a Twinkie swallow a valve with no warning. Sudden failure of an engine. Had it been in the Mooney I would have had to put it in the dirt.

Had a friend lose BOTH engines on a DC-3. One blew a cylinder suddenly with no warning. The other blew the master rod bearing on the same flight while at METO power trying to make an airport. Didn't make it. Went into the desert at night. Both sudden without warning. 

A friend had a crankshaft fracture in half at a rod journal, in a Cessna 140 while in the pattern. Sudden, without warning. The cause was a crank regrind at O/H  by a car machine shop without a radius at the grind juncture causing a high stress fracture prone corner. 

Well since I was responding to "this" discussion and not making a general statement about airplanes that quit making power, I still stand by my statement. 

The context here is whether an overhaul would prevent the failure of the engine. And while running out of gas might be just as disastrous as blowing a cylinder off from the perspective of the poor guy in the left seat, it wouldn't apply for this discussion as there's nothing about an engine overhaul that would have prevented that "engine failure."

There are plenty of examples of freshly overhauled engines that have failed as well. And it's also very unlikely that Lycoming or Continentals TBO calculations assume the best of modern engine monitoring, oil analysis, or borescope technology either. 

Everyone is entitled to their opinion on this topic and I don't think any opinions are wrong. All I was stating, and I still believe that with PROPER usage of a modern engine monitor with data logging, and with regular oil analysis, and with regular borescoping of valves, an engine such as this that has been running problem free for a thousand hours, will not just suddenly fail but rather will give advance indications. So without any regard for cost and only thinking of safety, I would continue to run the engine until it shows signs of failure.

[BKlott]

14 minutes ago, salty said:

Wasnt planning on it. I might pull it and repaint it. 

As a suggestion, you should have it pulled and sent off for an x-ray type inspection. This way any cracks or other issues can be identified and properly repaired. My IA told me that all but one of the mounts that he has sent off for inspection over the course of his career needed some repairs. 

Remember, that mount has been supporting that engine weight for some 52 years and some 2,600 hours of flying time, during which it was exposed to heat, vibration and G forces along with some significant temperature changes. How confident are you that the structure has no cracks in it?

Something to consider.