I’m pretty sure that the fuel metering is off since the fuel flow is a bit high and I can’t keep the engine running below 1,000RPM. But in order to adjust the fuel metering, I need to verify that the tach is reading accurately.  So I borrowed an optical tach and did another engine run.

So with Malcolm holding the optical tach, I ran the engine at a couple power settings and the panel was showing the exact same RPM as the optical tach.

While I was doing that I also tested both alternators. The primary alternator was working fine but the secondary alternator was not producing power. While troubleshooting, I discovered that the co-pilot side EFIS didn’t even show the secondary alternator.

EFIS-1 on the left and EFIS-2 on the right

After a bit of research, I discovered that there is a software update for the EFIS that fixes this issue. So that will get done of the next trip down.  I doubt that is the reason for the inoperative secondary alternator but I’ll tackle that after the software update.

So at this point, the wheels have been aligned, the fuel tanks have fuel in them, the electrical system is complete. In short, there’s nothing that needs to be done to start the engine.

So I drained the oil down to 8 quarts (I had overfilled it as part of the long-term storage), pulled the upper (desiccant) plugs and removed the covers from the exhaust and intake.

Malcolm came over to act as a pair of eye watching the engine for any problems (with the engine in back, you can’t see it from the cockpit). We pushed the airplane out of the hangar and with the mags off, I cranked the engine for about 5 seconds to get oil circulated.

Then I installed and connected the upper spark plugs, looked things over one last time and hopped in. Malcolm was positioned just by the left wing with the fire extinguisher (just in case). I primed the engine and Malcolm say fuel coming from the bottom of the engine. We looked things over and discovered the fuel supply fitting at the forward baffle was loose. Considering all the fuel fittings, I’m surprised that I only missed one.

I tightened it and tried priming the engine again. No leaks this time.

Then I turned the left mag on a cranked the engine. It tried to catch but never really started. Malcolm noticed that only one side seemed to be firing. Tried a couple more times and it finally caught and started. But it was rough. And it stalled out after about 10 seconds.  I noticed that the EGT for the #4 cylinder was non-existent. So I guessed that the bottom plug had gotten fouled due to oil getting into the cylinder from being overfilled.  When I went to remove the ignition wire, I discovered it was loose. When I checked the other lower plugs, they were all loose. However long ago that I had built the baffling and removed and reinstalled the ignition wires to route them through the baffle, I never tightened them.

So a few minutes later, they were all tight.

Back in the cockpit, and it started right up.

Run #1

I ran the engine for about 10 minutes until the oil got up to about 320 degrees and the EGTs all came up. I noticed that the #4 EGT was still reading zero. The CHT was reading about the same as the other 5 cylinders so I knew it was making power. Once I shut down the engine, a quick check with the IR thermometer showed the same temp and the other cylinders. So it had to be a loose connection or a bad EGT probe.

But it was late and it’s always good to leave on a high note. So we put the plane back in the hangar.

The next morning, I replaced the connectors for the #4 EGT probe and we pushed it back out for run #2.

Run #2

Engine started right up.  But it’s still not quite right. I called my A&P/IA friend and he said that it was probably going to need to adjust the fuel injection system. Even though the engine shop ran the engine after rebuilding it and would have adjusted it, he said that it’s not unusual to have to do again. So that will happen on the next trip down.

This turned out to be a real pain.

I was expecting a relatively straight-forward process.  Something along the lines of add 5 gallons, press a button, repeat, etc.  That’s why I added the shut-off valves on the last trip.

Then I discovered that my fuel probes have five “setpoints” (Empty, 1/4, 1/2, 3/4 and Full). Which means that I have to fill the tanks to determine how much they hold, empty them, then refill while defining the setpoints.

So I removed the lines between the strake tanks and the sump, attached four feet of flexible line to the strake tank, ran the line out the main gear opening and attached the valve at the end. This way I can drain the tanks without too much fuss.

I borrowed eight 5 gallon fuel cans and had them filled at the FBO (I’ve been hoping for 45 gallons per side, but I didn’t want to get more fuel than necessary so I started with 40 gallons) Then carted them over to the hangar.

Then I started filling the tank and checking the level after each 5 gallons with my 12″ scale.

And 40 gallons just barely fit.  A bit disappointing since I was hoping for more capacity.  So I drained the fuel out… Which took about 7 minutes per 5 gallon can (so about 45 minutes to drain a tank). And that’s when I realized that the plane wasn’t level.  I had neglected to tighten the collar on the right jack and it leaked down so that the right wing was low. I raised the jack until the plane was level and then moved over to the left side. After putting in all 40 gallons, I still had about 1/2″ left. So back to the factory to borrow another 5 gallon can, over to the FBO to get it filled, back to the hangar and poured it in the left tank. It didn’t take much before it was full but it looks like just shy of 42 gallons.

Then I drained out the fuel and refilled defining the fuel probe setpoints with “Empty” at 2 gallons, 1/4 at 10 gallons, 1/2 at 20 gallons, 3/4 at 30 gallons and “Full” at 41 gallons (although the probe looks at anything over about 35 or so as full).

Then I drained the left tank and refilled the right defining the setpoints the same as the left side. When I was finished, I determined the right tank holds just a little more than 41 gallons.  So I decided to call the fuel tanks at 41 gallons.

Then I drained the right tank (for the last time), reconnected the strake to sump fuel lines and dumped the fuel back in. After a short period the fuel equalized between the two tanks and I was done with th  at task.

Vortilons are small tabs which extend forward from the leading edge of the wings. The word actually comes from two words: Vortex and Pylon. Here’s some aerodynamic science for you:

Vortilons officially first appeared when Douglas was developing the DC-9.  As is typically the case, rather than re-invent the wheel, previous technology and parts are used to speed up development.  In the case of the DC-9, Douglas engineers, decided to use the same wing design as the DC-8. The difference between the two is that the DC-8 had four engines under the wing (on pylons) where the DC-9 had them on the tail.

When they started testing, the engineers discovered that the wing had significantly less lift at low speeds (landing and takeoff) than the DC-8 wing. Since the only difference in the wing design (other than the engine location) were the pylons, they installed just the engine pylons under the wing.  And the lift returned! So the engineers made the pylons shorter and shorter until the lift diminished.

The result became what is now known as a vortilon.

What happens is with swept wing designs (although similar behavior can also occur on non-swept wings), as the angle of attach increases, the flow of air begins to move span-wise (toward the side) as opposed to chord-wise (front to rear).  One of the solutions is to install a fence.

Mig-17 with stall fences.

This prevents the air from moving towards the wingtip. The down-side to stall fences is that while they are only needed during high angles of attach (landing and takeoff), they incur a permanent drag penalty.  Anything sticking out creates drag.  And drag reduces speed.

Vortilons create a rotating spiral of air (vortex) that acts as a stall fence. But they are only doing this at high angles of attack. During low angles of attack, the vortilons aren’t doing much of anything.  Think of vortilons as stall fences that mostly retract when not in use.

Here’s a Starship (because, you know, they’re cool) where you can see four vortilons on the lower, leading edge of the wing.

The vortilons which come with the kit are rough fiberglass and about the same size. Because this is a highly visible, finish type part, I deferred it to the guru of all things finish (Malcolm).

Here is a picture of a set of vortilons (from Jorge Bujanda’s site) after being trimmed down.  The size goes from large to small as they go inboard to outboard.

Then they have to be filled, primed, sanded, filled, primed and painted.

Now they do stick out a ways, so it would be real easy while working on the plane to run into one and break it off. So I’m not going to install them until I’m ready to fly. But the positioning is rather important. The location is easy to measure. Just measure out from the wingroot 18″, then 36″ more and then another 36″.  Getting them aligned is another story. For that Malcolm has a template he created.

First a mark is made on the leading edge. To get it perfectly on the leading edge, I kinda made a tool.

Then I placed the pencil against the leading edge with a level. While keeping the level/pencil perfectly plumb, I moved everything across the leading edge of the wing. The result is a perfectly straight line which is exactly on the leading edge of the wing.  Now I probably didn’t have to be that precise, but it wasn’t that hard.

Next the template is aligned with the mark on the leading edge and rolled under the wing.  Then simply mark the wing on that line.

Now when it’s time to install the vortilons, I just have to line them up with the mark.

All finished for this trip. Got a lot accomplished.  Battery installed, electrical systems tested, control systems connected, fuel shutoffs installed. Malcolm is finishing up the priming and painting of the sparrow strainer, vortilons and cowling.

Some final pictures as I was leaving.

And because I’m supposed to have pictures of me with the airplane…