Not long ago, there was an oil leak on the right engine of a Cessna 414. The leak was significant enough to come out the louvers on the top cowling in flight. There was oil all over the rear inboard area of the engine, so the big question was, “Where is the oil leak coming from,” or “Where is the source?”
With so many possibilities, it was difficult to find the leak.
After multiple cleanings and ground runs, it was becoming more clear.
It was still however, hard to be certain. It seemed to be coming from the inboard forward base of the oil cooler. A flashlight and small mirror were somewhat helpful to see the area:
The borescope was also helpful to take a closer look:
Finally, after making the best evaluation I could without disassembling anything, I told the owner I was fairly certain the oil cooler was leaking… it seemed there might be a small crack in the oil cooler.
The annual inspection was already scheduled for this airplane, so it made a good time to verify the oil leak. The owner is an A&P, and he removed the oil cooler himself. I was hoping I had not steered him down the wrong path on this one!
He discovered it’s not an easy task to remove the oil cooler from his engine, but he persisted and got it done.
He sent me a text message and told me he had removed the oil cooler and when they first looked at it, he was not sure it was cracked. But after pressurizing it with 5 pounds of air pressure, the leak was obvious.
About the oil cooler, he told me “I tell you it was a job getting that off.”
The black circled area is where the crack was:
And here’s the really fun part… watch this video to see the bubbles confirming the source of the oil leak:
Here’s the engine after the oil cooler was removed… definitely “major surgery!”
This was the main maintenance topic in this week’s podcast, and we also talked about these items as well:
Aerostar voltage regulator adjustment.
Alternator charging system troubleshooting.
Our upcoming trip to Maui!
Thanks for listening, and we’ll see you in the next episode!
I recently removed a magneto from a Piper Cherokee, and my curiosity about why the magneto had failed got the best of me.
I took the mag home, sat down at the kitchen table, put my grandson Spencer on my lap, and took the magneto apart! It was great fun having him help me 🙂
Before long, we had the case apart, and it quickly became obvious why the magneto wasn’t working… there were 6 broken teeth on the distributor gear! And 3 of the broken teeth were together in a row, making it impossible for the distributor gear to mesh with the drive gear… this mag was completely dead.
It had been more than 600 hours since the last 500 hour magneto inspection.
I wonder how long it had been since the first tooth broke… we’ll never know.
But it does remind me of the importance of doing 500 hour magneto inspections. For Part 91 airplanes, it’s a recommendation and not a requirement, but in this case, I think the recommendation is a really good one.
You can listen to the podcast episode for more details about the troubleshooting process on the magneto, and here are some other items also included in this episode:
Some King Air flying this week (I never get tired of the “view from the office!”)
Our complex ATC clearances we received on the way to the Boston area.
The annual inspection I’m currently doing on an A36 Bonanza… here’s the overhauled alternator drive coupling I installed because the old one failed the slippage torqe test:
Our IA renewal seminar at Blue Ridge Community College… it’s always a good time to see friends, learn some things, and satisfy the FAA requirements to keep my IA certificate current.
And finally, Maria and I are getting very excited about our trip to Hawaii! We’re going to visit John and Leslie Caubble on Maui, and I’ll be working with them on the flight school airplanes at FlyMauiHI.com It’s going to be a grand adventure!
Here’s the short answer: Worn and contaminated brushes inside the alternator. Check it out:
My theory is that the excessive amount of carbon dust from brush wear was causing a short circuit situation between the brushes, and not allowing the field circuit in the alternator rotor to be properly energized for normal operation.
Here’s a comparison of the old and new brushes:
This story comes from a recent situation on the right engine of this Aerostar aircraft:
Since the alternator has externally removable brushes, it turned out to be a minimally invasive surgery to fix the problem. I cleaned the brush holder and also the slip rings inside the alternator, and after installing new brushes and reassembling everything, the alternator performed flawlessly.
Listen to the audio to hear the full story.
This episode also covers some of the email responses I received last week from some listeners, and here’s one of the highlights:
Glen sent me a photo of he and his dad in front of his Piper Cherokee… I love to see different generations enjoying aviation adventures together!
One more fun fact: Glen’s mom took her private pilot check ride years ago with Glen in the back seat of their Cessna 175 when he was 3 weeks old! What a great story!
Thanks Glen, for sharing some of your story with us!
This episode also covers a recent trip to Charlotte in another Aerostar, and the interesting routing we got from ATC on the way there… definitely some great IFR and ATC lessons to observe and learn from this one!
The Charlotte trip also sparked some conversation about twin engine charging systems, and paralleling issues that can happen… this situation is still in process, and I’ll try to give an update sometime in the future.
Finally, I had the privilege of joining Carl Valeri, Tom Frick, and Bill English on episode 301 “What is Your Most Challenging Approach” of the Stuck Mic AvCast. It was great fun talking about challenging approaches, both instrument and visual approaches.
Clark and his family came to Virginia to visit his mom recently, and on the way up from Florida, the right vacuum pump quit working… as often happens when a vacuum pump quits, the drive shaft had sheared off, saving the engine from catastrophic damage.
In times like these, a good question to ask is, “What does this make possible?”
In this case, it made it possible to tackle a maintenance project with a good friend!
You can listen to the audio in this week’s podcast to hear about how I got to know Clark, and how he became the kind of friend I would want to go the extra mile for, whenever I can.
We changed the broken vacuum pump, installed new filters, and got him all set for the trip back home. (Ask him if he got to fly much on the trip… the answer would be no, because his wife is learning to fly and she took over the controls for most of the trip 🙂
It’s always fun when you can get an airline captain turning wrenches! Clark is very mechanically inclined, and I think the whole experience put a big smile on his face.
Another highlight recently on a Saturday morning was when I took my mom for an airplane ride… she’s 86 years old and still very happy to get in a little airplane and go flying! We had a great time flying around the beautiful Shenandoah Valley. You’ll hear about this story in this episode as well.
And finally, my wife Maria and I have an exciting trip planned in just over a month from now… we’re going to Hawaii for the first time! Our friends, John and Leslie Caubble, operate a flight school on Maui, so we’re going to visit them and I get to help work on the flight school airplanes… we’re super excited about this adventure!
You can learn A LOT more about John and Leslie through their two podcasts, The Aloha 360, and Fly Maui. They are simply GREAT people!
This is a good looking exhaust valve with a nice concentric appearance. However, the compression was very low at 8/80.
I lapped the valve, hoping it would improve the compression test result… it only came up to 10/80, and that was after running the engine again and getting it nice and hot.
Although the valve face showed a healthy appearance, the seating area was telling a different story. Check out the following borescope photo of the seating area showing a possible leaking area:
It appeared there was abnormal wear on the valve seat, and the valve was not able to seal well, causing an unacceptably low compression result.
Listen to the audio for more details on this one.
I asked the question, “Borescope or compression tester… which one is better?”
Let me know what you think after listening. I’m curious to hear your thoughts.
Just click the button over to the right and record a brief audio message for me.
Thanks!
We ended up sending cylinder #5 out for repair, and then reinstalling it.
We did a test flight today, and everything went very well… ready to go for another year!
Here are some links to information on cylinder / engine break-in procedures:
Have you started flight training, but stalled out along the way?
Did you finish that instrument rating?
How about the commercial certificate, or CFI, or even CFII?
Ever dream about getting your A&P?
Have you wanted to be an airline pilot for years and years?
Did you give up along the way when you ran out of money?
Maybe you want to be a fighter pilot.
Maybe you want to ferry airplanes around the world.
Or some other crazy, wonderful dream!
If you resonate with any of the above, you just might be an excellent candidate for aviation career coaching with Carl Valeri.
Last year in 2022, when I was feeling grumpy and restless in my full time A&P/IA job (and longing to fly more,) I signed up for a career coaching session with Carl Valeri.
It was one of the best decisions I made in that time of transition.
Now, I have a pilot position flying for a local company in their King Air 350, and I work part time in my previous A&P job, and I’m loving it so much more!
As I’ve shared about my work transition, I’ve heard from a fair number of people who have also thought about pursuing a flying job, or getting their A&P, etc.
My encouragement it this: If it’s in your heart to do it, and you can’t stop thinking about it, then go for it!
I know there are all kinds of obstacles to get past like fear, doubt, money, nay-sayers, etc.
But you don’t want to look back years from now and regret not going for it and at least trying to reach your dream.
Carl is uniquely suited to give wise counsel to people pursuing an aviation career.
He’s an airline captain and airline training instructor, aviation podcaster, and aviation career coach, with such a wide variety of experience in aviation. He certainly has his finger on the pulse of aviation at this current time.
Carl helped me sort through my ideas, put me in touch with some key people for me to talk with, and gave excellent recommendations for how I could move forward.
I’m super grateful for his wise counsel.
How about you?
Could you benefit from talking with Carl about your aviation dreams?
If yes, then sign up here: (Be aware, you may need to sign up weeks in advance since Carl’s schedule fills up quickly.)
In my opinion, Carl Valeri is one of the best aviation career coaches in the world… he really helped me last year when I paid for an hour of his coaching. It’s a super valuable resource, and I highly recommend him… it is money very well spent if you are trying to decide the best way to reach your aviation career goals.
If you want to get to know Carl before you sign up for coaching, the best way to do that is by listening to both of his podcasts:
How long should the battery last in a small, piston-powered airplane?
That’s a great question, and we are talking about it in this week’s podcast episode.
Tune in to hear the story behind this 24 volt battery in the photo, as well as the story of another battery, a 12 volt one in a Citabria owned by our good friends, Leon and Wynne Johenning. (Find out what prompted him to replace the battery.)
I had an opportunity to fly in an Aerostar the other day… it was going to be a fairly long trip to the destination, with one fuel stop along the way.
As we climbed out of the Shenandoah Valley in Virginia toward the mountains to the West, we discovered the combustion heater for keeping the cabin warm was not working. After a brief conversation about what to do, we decided to keep going. Our two passengers seemed willing to tolerate the cold if they could still get to their destination. Thankfully, it was not as cold as it could have been for a January day.
We arrived at the destination on schedule and although we were at a small town airport, there was a small general aviation maintenance shop there, and one of the guys agreed to take a look at our heater.
As he removed the spark plug from the heater, the ignition lead came apart and a piece of it stayed down in the spark plug. Amazingly, he had the necessary part to fix the ignition lead, and the heater lit right up, no problem.
The trip home was wonderfully smooth and uneventful… and the heater worked!
Although we don’t hope to repeat that experience any time soon, we certainly made a memory that day.
I wish I had the freedom to tell you about the town we were at… it’s a cool name, and the AvGas price was great ($5.00 per gallon!)
Also in this episode, I talked about our recent trip to Greensboro NC for a service center update to our avionics system. Since the weather cleared up quicker than I expected, I managed to snag a few photos of the King Air the morning we dropped it off.
Here are the highlights you’ll find in this podcast episode:
My latest assignment at Classic Aviation – Installing the freshly overhauled engine in a Cessna 172 that is almost complete after an extensive rebuild process.
Some emails I’ve received from listeners with fun feedback of multiple types.
Some listener thoughts about home simulator systems.
Some resources I’ve found helpful in sharpening up ATC communication skills.
Here are some of those fantastic resources:
Live ATC: Choose an ATC facility somewhere in the country, and listen in! LiveATC.net
Opposing Bases Podcast – 2 guys who are both air traffic controllers AND pilots, and they laugh a lot! This is a great resource to hear about real world situations between ATC and pilots, and how to deal with weird or out of the ordinary situations. OpposingBases.com
A big thank you to all the listeners who have sent information and thoughts about home simulators! This is a great way to practice instrument approaches without burning any gas 🙂
But first… My friend and podcast listener, Chris Wieczorek, flew into SHD recently and we ate burgers for lunch. It was a win-win. I provided the ground transportation, and he bought lunch!
The conversation was very inspiring to me, and Chris was kind enough to send more feedback later in an email, with some thoughts about the future of this podcast among other things.
Go ahead and listen to the audio for more of Chris’ thoughts.
Thank you Chris!
Oh, and he decided to go with the burger that is my wife’s favorite… the “Bacon ‘N Blue.” I stuck with my ‘ol favorite, the “Philly Cheeseburger.”
This episode also includes some concluding thoughts about this Bonanza:
Since I’m still working part time at Classic Aviation LLC, I’m able to continue with some selected maintenance like the annual inspection on this Bonanza.
I rolled it out of the shop the other day and did the post-annual engine runup. Here are some specific things I needed to check and why:
Check propeller for proper operation and no leaks (it was overhauled.)
Check prop heat for proper operation (new deice brushes and new heating elements on prop blades.)
Check alternator for proper operation (new alternator and drive coupling.)
Check analog RPM gauge (repaired broken ground wire connection.)
Check for no leaks at crankshaft seal (new seal was installed.)
Check the #2 EGT (a new probe was installed.)
Everything worked well, and the airplane is finished including the paperwork. Listen to the audio for more details.
In the second part of this episode, I shared the responses I received after sending out an email about the approach we flew into JFK recently. There were some really fun ones in there, including some airline pilots who have flown that very approach, the RNAV Z 13L approach into JFK. Thanks to everyone who sent feedback on that one!
Among the responses, Troy sent me a link for a great video to see what the “lead-in lights look like at night for that approach. Check it out:
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