I logged 8 hours for this because of all the research and running around for stuff to make a test rig from. I realize I can't do my own transponder check, but I wanted to leak check the plumbing while I still had good access to everything in case there was a problem. For pitot, I used 3' of 1/4" rubber hose from ace hardware. I slipped one end on the pitot line where it will eventually attach to the tube and the other end to the AOA line similarly. Made them airtight with a couple of twists of safety wire and a wrap of electrical tape for good measure. I folded the rubber hose at the approximate center and then just rolled up both sides simultaneously which pressurized both the pitot and AOA sides of the GSU25 which must be done to avoid damaging the unit per Garmin guidance. once I saw 150kts, I pinched the hose with a spring clamp to trap the pressure I had, but because of a slight lack of precision in locating the clamp I ended up with an indicated airspeed of about 145. 43.13 gives a general reference that Garmin basically parThe GAP26 manual says that the standard when testing with the probe removed from teh aircraft is 150kts with no more than a 5 kt per minute leak down. I had effectively zero leak down with this setup, so thats good to see! For the static side, FAR23 says run it up to 1000 AGL with no more that a 100'/min leak rate. I accomplished this with a homemade vacuum rig. It started life as a suction cup that was meant to hang something in a shower, then I drilled a hole and inserted a cheap barbed regulator from an aquarium bubbler. I then ran enough aquarium tubing that I could operate the rig and see the altimeter, and installed a syringe on the other end that I got from the farm supply store. I taped over one static port with a small piece of electrical tape, suction cupped the other one, and slowly pulled a slight vacuum on it. When I got to 1,000 AGL I locked down the aquarium regulator. I did this test twice and got a 90' leak the first time and 70' the second time. Within tolerance both times. I suspect that the actual leak rate is actually lower, but this was with el cheapo aquarium parts and it still passed, so I'm calling it good. I've attached a some pix of the airspeed test, but I ran out of hands when doing teh static side and didn't get a picture.