Skip to main content

Good news and... not so good news

My plane is in for its annual inspection and I just got off the phone with the shop manager. The good news is that they're making good progress on the plane, and both the landing light and trim tab piece arrived in time. I do need to take the books out to the shop, which I will do tomorrow afternoon.

The not so good news is that they found some metal in the oil. When I had the pre-buy inspection performed back in January, I had them change the oil as well. The note in the engine log book states that no metal was found in the filter. If metal is in the filter now, that indicates that some unexpected wear has occurred.

As far as I know, the engine has been running fine. So I have no real idea what might be causing this. Thinking about it, though, there is one potential cause, though it seems strange to me that it might be related.

Several flights ago, when I was performing the magneto check during the run-up, I accidentally turned the ignition switch one step too far and turned it completely off briefly. I immediately turned it back on and the engine restarted, but it seemed to, for lack of a better phrase, hit "hard". I suspect there was a bit of extra fuel in one or more cylinders due to fact that the mixture was not at lean cut-off like it would be during a normal shut-down. I suppose it's possible that there was an unusual amount of pressure in the cylinder for one cycle, and that may have caused some damage to the rings or the piston. I don't think it's likely but, while I have an excellent understanding of the operating principles of an internal combustion engine, I'm not an expert on this kind of thing.

The plan is to finish the inspection, and then run the engine for around five hours. Then we'll do another inspection of the oil filter to see if any more metal is ending up in it. If it looks okay, we'll do it again at around 25 hours, than again at 50.

The engine has close to 1600 hours since it was overhauled. It *should* be good for at least another 400 hours or more, but sometimes things happen and it doesn't last as long. We'll have to see how it goes. Obviously I hope that no major repair will be required, let alone an overhaul or replacement. That's when you start talking real money. If it comes to that, though, well, I knew that there was some risk in purchasing an airplane of this vintage, regardless of how well-maintained it's been and how good a condition it's in. I'll just have to deal with it as it comes.

Comments

Post a Comment

Popular posts from this blog

Predicting the weather is hard

At least, it's hard for this region of the country. I like to say that predicting the weather for the Puget Sound region is far more an art than it is a science. Early last week, the weather forecast was for pretty much crappy weather for the foreseeable future. However, because of the chaotic nature of the atmosphere around here, especially at this time of year, the forecast is always subject to change. As it turns out, the weather was actually nice enough last Friday afternoon (December 17) that I was able to go up for about an hour and a half. One of the reasons I went up was because I had filled the tanks after the previous flight, and I wanted to burn off some fuel in case I was able to take my father flying while we visiting from Arizona. As I'm sure I've mentioned, the weight and balance of my plane is such that I'd be over maximum weight if I had a passenger in the front seat, the required ballast in the baggage compartment to stay within the forward CG limit, a...
1 comment
Read more

A digression, if I may...

The other night, after almost 50 years, the Saturn V was dethroned as the most powerful rocket ever successfully launched by humanity. I use the word "successfully" because the Soviet N1 rocket actually generated more thrust at liftoff, but all four launch attempts ended in failure. For the first time since Apollo 17, a true moon rocket lifted off from Kennedy Space Center in Florida, carrying a spacecraft capable of carrying humans back to the moon. This Artemis mission is a test flight, so no astronauts are on board the Orion spacecraft. Despite that, it was a spectacular launch. Because the SLS launch vehicle has a higher thrust-to-weight ratio than the Saturn V, it rose from the launch pad much more quickly than it's predecessor. I think it's a bit heavier than the Space Shuttle, but it has more thrust due to an additional RS-25 engine, and more powerful solid rocket boosters. Watching it rise into the night sky, I was excited, but also a bit melancholy. This was ...
1 comment
Read more

Approaching the annual

I know I haven't been posting much, but that's mainly because nothing much of note has been happening. I've been flying, but not really going anywhere in particular. The engine continues to run very well, and the plane is still solid. I was hoping to do more "destination" flying this year but, for whatever reason(s), it didn't really happen. Next year, hopefully.... On the horizon, though, is the annual inspection. It's already scheduled for mid-December, since the last annual is good to the end of that month. I've also arranged for it to be an owner-assisted annual. I'm told that every airplane owner should do this at least once and I can certainly understand why that is the case, even before I do it. I will be learning about my airplane in a way that nothing else will match and, incidentally, save some money at the same time. I'm looking forward to it. Leading up to the annual, I have been compiling a list of squawks that I want to take care ...
Post a Comment
Read more