Over the course of a couple of evenings this week I checked out the lights and installed the pitot tube, checking the heater function. I’m trying to fully test the electrical system so I can start troubleshooting and addressing any issues.
The pitot tube installation went mostly according to plan. The Vans plans include a simple, unheated pitot tube, and a lot of builders opt for an upgraded pitot tube with AOA and heat, as I have done with the Garmin pitot tube. One of the considerations for the builder is how to bend the pitot and AOA aluminum tubes coming out of the top of the pitot unit to avoid interference with the aileron push tube. My bends were good, and no changes were needed. Installing the 90 degree aluminum fluid fittings was a bit challenging as access is somewhat limited. I was able to torque them sufficiently so hopefully they won’t leak.
The wiring was where I ran into a problem. I had previously set everything up, and all I needed to do was insert the crimped pins into a molex connector, then plugging it in. Unfortunately, the pins were slightly too large for the molex connector, and in the process of trying to make it work, one of the pins pulled off the wire. I’m going to need to redo the wiring, so I’ll be looking into other options. I may just use butt splices and ditch the molex connector. I was able to rig it temporarily so I could test the heater unit using the panel switch, and everything worked as expected.
The rest of the aircraft lighting mostly worked as expected, although I had a list of squawks to troubleshoot and resolve. The first issue was the FlyLED Combo spotlights on the right wing were not illuminating. This was a lost connection, and fully seating the molex connector resolved the issue.
The second problem was the tail light not working. This turned out to be an inadvertent switching of the wiring polarity, and switching the pins in the tail fixed the issue. I had previously wired up a small molex connector and successfully tested the tail light. What I hadn’t considered at the time was that the wires need to pass through a small hole in the Vertical Stabilizer, and I had to remove the molex connector. Rather than messing with a molex connector (just another possible point of failure), I used d-sub pins and insulated the pins with heat shrink. This is when I had switched the wires and introduced the issue. The biggest pain was the lack of access to wiring. With the tail spring right under the forward end of the tail fairing, the fairing can only be moved about half an inch, and I had to flex the side of the fairing to reach in and grab hold of the service loop and then remedy the issue.
That leaves two lighting issues to troubleshoot, 1. One row of red LED position lights isn’t illuminating and 2. The wing tip strobe lights are very dim.
I reached out to Paul at FlyLED and he has pointed me in the right direction to start troubleshooting to isolate the problem. Hopefully some investigation will identify the issue and I can get these problems resolved.
Next I’ll be testing the trim system, and eventually the magnetos.
I also heard back from Vans about an interference issue I’m seeing between the fuel tank bracket and the fuselage side skin. I’m planning to trim the corner off the bracket, which I hope to do with some careful use of a small cutoff wheel.
