Last weekend I had to work to deliver a product launch, so no airplane. This weekend, I had a list, and I knocked out a bunch of stuff on it. To sum up:
- Tensioned and safety-wired alternator bracket
- Removed protective plastic from aft canopy and removed tape residue
- Relabeled mag switches and made “OFF” labels for everything else
- Reconfigured quadrant for extra travel on governor
- Added a wider heat shield to protect the throttle cable
- changed out a too-short bolt on the purge valve cable bracket.
Apparently the way you do alternator belt tension is by increasing belt tension until it takes 12 ft/lbs of torque on the alternator nut to slip the belt. That’s it. That also gives you the 1/4″ deflection (on a new belt) called out by the usual procedure. This is important, because a slipping belt can cause over/under voltage problems. I did that, and safety-wired the bracket tension bolts together, like so:
When I put the aft canopy in all those many moons ago, I left the protective plastic on it, because why not? Why subject the vulnerable plexiglas to my fumbling ministrations while I’m climbing in and out of the tailcone to adjust one thing or another, swinging tools and wires about? Because once the canopy is attached, it’s difficult if not impossible to get all the plastic out from between the roll bar support and the canopy. I had to put a space heater in the cockpit and run it for a while, until it was a balmy 75 degrees and the plexi and surrounding aluminum were warm to the touch. I took out all the fasteners and removed the aft canopy section, which I put on the bench, then removed the rest of the protective plastic and cleaned off all the tape residue I couldn’t get to before. 100% better.
The magneto switches on the panel were cryptically labeled “MAG 1” and “MAG 2.” I don’t know why I thought this was a good idea, and it broke with common practices in aircraft UI/UX design. I relabeled them “L MAG” and “R MAG” because that made the most sense, and that’s how everyone else does it. While I was in a labeling mood, I made about a dozen or so “OFF” labels to describe the down position of most of my toggle switches. The double-throw switches like flaps up/down already had good labels in both directions, but there wasn’t anything labeled “OFF” anywhere. The switch pointing toward the function described seems obvious to me, but apparently it isn’t to whoever wrote that reg at the FAA, so now everything is labeled according to the AC’s.
Like I said, there were odds, ends and annoyances. Firewall forward, there was the matter of a heat shield, a too-short bolt, and the prop governor travel.
I did have a shield in place at this spot, but I remembered I had an extra double-wide one, so I put that one on in its place. On the topside of the engine, I changed out the bolt holding the purge valve cable. It was a temporary thing when I did it, and it didn’t have the required number of threads showing to meet spec, and since it’s pretty important that the purge valve remain closed in flight, it’s also important that everything connected to it is not half-assed. This is what the proper bolt length looks like:
As to the prop governor, if you’ll recall from last time, the prop didn’t cycle at the low end of the throw. The quadrant was only moving the lever arm about halfway through its arc of travel. The simple fix to that was to drill a #12 hole about 5/8″ up the quadrant lever from the original one and voila, I get me 75-80% travel instead of 50%. That story ended with a quick runup to 1800rpm and getting the prop to cycle, so that’s good enough for now. Whether or not I have the rpm set right due to the arm position relative to the governor shaft is another story, and it will be resolved on either a full power run or first flight. Even so, the engine is more responsive, now that it’s firing on all the plugs, which are now more or less synchronized in their ignition, so that’s a plus as well.
What was really awesome about this weekend was that for the most part, it was forward motion, not playing catch-up. New things got done and good fixes were made, rather than unsuccessful stabs at a persistent and difficult problem. There’s still a bunch of stuff to do to get ready for first flight, but I think if I can keep up the pace, I’ll be on track to fly it in early 2014.