In my fourth quarter at South Seattle's Aerospace Maintenance Technology school, I just finished giving an ancient motor a makeover, rebuilding everything around the engine except the engine itself, and I learned quite a bit.
In my second quarter I learned circuit analysis and electronics, and in my third quarter I "overhauled" a Lycoming GSO-480 (which will never run again) and various sections of various jet engines (which also will never run again). This quarter, we took a perfectly good Continental C-85 (also known as an O-190), rebuilt its magnetos and carburetor, and assessed it for Stuff That Could Be Done Better.
The primer pump is marked "WIND SHIELD WASHER." Of course we kept it.
On an engine that hasn't left the ground for decades, and has only been serviced by students for the last forty years, you can find quite a bit of shoddy work. My instructor tasked me with repairing the ugly work, as well as installing new instruments and controls.
The barrel for the starter handle is the casing of an 18mm spark plug. We kept that, too.
The first thing we assessed was where to put the new controls and instruments on our old control panel, or whether they would fit at all. Of course they wouldn't, so I got to build a new dashboard that would accommodate the new gear.
Every other engine's console looked like it was made by Thembrians.
The next step was to start stuffing new gear in and finding the routes that all the wires and hoses would go. We learned some hard lessons during this part, especially when it came to working tired and practicing new procedures on things you don't love before you work on parts you can't afford to foul up.
Two weeks learning new fabrication skills and applying them to a fever dream of trigonometry and—oh god, I have to cut holes in it now?
What followed was too fast, and too much work, to stop and get many process pictures, but it involved a lot of bold decisions and bravery tests—for a perfectionist, anyway. We installed the new instruments, new probes, new fuel lines, and plumbed all the leads that would run between them, and planned a layout for the electrical system that hopefully wouldn't make future students curse "the jackasses that made it this way."
With everything test-fitted, and all design and layout decisions finalized, it was time to remove the panel and paint it. I want to say we did a better job than two tired students should be able to do with a rattle can of wrinkle coat and a too-small paint booth, but we set the bar rather low, I'm afraid. Painters we are not.
It's wrinkle coat—another layer should just cover up the runs on the first layer, right?
At long last, we were able to get everything installed and tidied up. The wires all found their permanent homes, safely snugged away in fire sleeves and cushion clamps, and all the flexible hoses were secured to the frame with much improved access to the magnetos (for future students to remove and reinstall, and definitely not curse our names).
Yeah, it could have been packaged with more attention to keeping it compact, but in the end it is a teaching tool, and I wanted to make the wiring very clear and understandable.
For more pictures of the finished work, and the riveting tale of the "smoke test," check out my Flickr album. Don't worry, the engine is running fine, now. Promise. I hope you enjoyed this tale, and seeing the transformation and preservation of a classic aviation engine. See you in the comments!