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Wischful Thinking
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Overhaul
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by Jay Wischkaemper
“You made the right decision.”
The words gave me a sense of fear and of relief at the same time. Relief that we made the right decision. Fear of what might have happened had we not.
As our mechanic, Gary Bradley, said those words, I was holding in my hand a main bearing from our engine. The inside of the bearing showed severe wear. Brass was evident where brass shouldn’t be seen. Running your finger across the inside of the bearing revealed channels of wear. The outside of the bearing also showed signs of scoring, indicating that it had been turning. Not good. As I later showed the worn bearing to Robin, our attorney partner, he remarked soberly, “I was flying over the Rocky Mountains with that a few weeks ago.”
The decision to which Gary referred had been whether or not to major the engine. It’s never an easy decision. There are times when it’s obvious that a major is needed. If the engine has reached TBO, four cylinders have low compression, and it’s using a quart of oil every hour, it’s time for a major. But rarely is it that cut and dried. It would be nice if an aircraft engine ran perfectly until it reached TBO, at which point you could be assured that it would implode if it went one hour over. That isn’t the way life is. That isn’t the way aircraft engines work.
Ours was one of those multi-timed engines. The top of the engine was overhauled with rebuilt cylinders 1100 hours ago. The engine didn’t use oil. It ran good. On this particular annual, all cylinders were in the 70s except one, and it was 68. The oil analysis appeared good. There wasn’t an excessive amount of metal in the oil filter. But the bottom of the engine had reached TBO and more. About 200 hours more. What do you do? After all, they do recommend those TBOs for a reason. But what could go wrong with the bottom end of the engine? We sat down with Gary and asked him what he thought. “Well,” he said, “You might get another year out of it, but you might also spin a bearing.” He told us that if a bearing did spin, it would likely give us warning before it totally failed, but he also warned us that the bottom end of Continental engines do not like to go past TBO. We might make it another year, or it might end up costing us more to try if we ruined the case.
There are two places where the word “might” is useless. Defusing bombs, and airplane engines. None of us felt comfortable with “might.”
Other factors that made our decision easier were that the prop had to be overhauled in any event. It had been 10 years, and in the overhaul, it turned out that it had a leak in the hub. The mags were also due for overhauls. All the stars lined up. Something told us all not to wait. While there are a number of excellent engine shops around and factory remans are always an option, in the end, we decided to have it done locally to our specs, reasoning that if there were a problem, it would be nice to have the guy who put it together local to gripe at. It also helps that Gary has a reputation as one of the best engine rebuilders in existence. We needed a new crank. Ours wasn’t a VAR, not to mention the fact that the bad bearing had also scored that journal on the crank. New ECI Titan cylinders would be used. Other than the cam, case, rocker arms, and rods, everything in the engine would be new or overhauled, and those items reused would be inspected. New vacuum pump. Overhauled fuel system. Alternator. Starter. Harness. Prop. Everything from the firewall forward. We even decided to replace the old EGT gage with one that might even give us an accurate reading.
It isn’t easy giving the okay to spend 25 grand on an engine, but it has to be done. That’s why you have partners. With all of us going out to check on progress, I’m sure Gary wishes there weren’t quite so many partners. He’d probably finish the job three days earlier if it weren’t for the time he spends soothing our tensions. The plane sits now like a wounded bird whose feathers can only drag the ground. Parts are out for inspection. The new cylinders and crank aren’t here yet. The parts that will become our overhauled engine are sitting in various places, waiting to come together to serve us another seven or eight years. Craig has agreed to do the first flight to break the new engine in. Hopefully he can get Robin to go as well. If anything did happen on the first flight, it would be a shame to have a plane crash without a lawyer on board.
So in a few weeks, it’ll be back together, and the scored main bearings will sit on the desk of John Frullo, one of our partners – a reminder of his five-grand contribution to the cause. And they will be a constant reminder to us all of why recommended TBOs should be taken seriously.
Texas native Jay Wischkaemper is a successful MassMutual life insurance agent based in Lubbock, Texas. He is a long-time partner in a Bellanca Super Viking, which he uses for business and pleasure.
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