Today I had a visit from Rob Hickman, Founder and CEO of Advanced Flight Systems, and Travis, his lead tech troubleshooter. They flew in from Canby, OR, just to fix my problem with the tach sensor. Wow. And fix it they did, in short order, with various instruments, and the latest version of their RPM board. It's great to have the tach working properly now, and to experience such fine service from such fine folks. Thanks Rob and Travis!

With the tach working, the plane now meets all technical requirements for airworthiness.

With things getting finalized in and around the cowl area, it was time to tune up the SCAT hose mounting clamps. The first photo shows MS21919 "Adel" clamps securing the bottom of the cabin heat valve's overboard heat dump hose. When the cabin heat is off, heat from the heat muff on the engine muffler flows down through this hose to be dumped overboard via the cowl plenum exit at the bottom, keeping as much heat as possible out of the lower cowl area. In the middle left you can see a blue tie wrap that's been holding the heat-muff-to-cabin-heat-valve hose temporariliy.

The second photo shows clamping of the carb heat SCAT hose in a curious shape that will keep it from chafing against control cables, wires, and the engine mount.

It was a big day, beginning with the oil change. The factory installed pickle (preservative) oil, which has been in the engine since its factory test runs were complete a little over four years ago was drained and new Aeroshell W 80 straight mineral non-dispersant oil was installed for break-in. The oil cooler was primed with new oil by slowly filling one of the two hoses and waiting for the other to overflow. Took 1/2 quart. Then both oil cooler hoses were finally attached to the AN6 flare fittings on the oil cooler adapter under the oil filter. The first photo shows attention to the task.

I also installed a two part Curtis drain adapter made for the Jabiru engine. It consists of a right angle "T" fitting, and a spring loaded valve going into a hose barb. For future oil changes, I won't have to take out a plug and manage oil drips. Just put a hose on the hose barb, put the other end in a drain pail, twist the valve, and the oil will go wherever I want it to go, no fuss, no muss, no oil flooding the bottom of the cowl.

After the adapter was in place, the plane was returned to level attitude (tail up) and the oil  sump was carefully filled to the mid point of the dipstick. Then the tail was lowered again in an attempt to "calibrate" the dipstick at the tail down ground attitude, however, in the latter position the oil didn't even read on the dipstick. The dipstick calibration process will have to be continued at a later time. Some builders with taildraggers have modified the dip stick to be longer so it will read the oil when  the tail is down, others haven't had to do that, depending on the type of plane and gear that it has. Even tricycle gear planes can vary in the degree to which the engine is or isn't level when on the ground.

Picking up on the last few little details at the engine, including a small bracket for a stabilizing clamp for the right side oil cooler hose. Some people don't bother with this, but the hose makes a turn around the front of the engine, which leaves a significant mass of the hose hanging out on a corner, subject to vibration and potentially worse, oscillation. As shown in the first photo, although the clamp is snug enough it's not going to slip at all on the hose, the clamp isn't really designed to hold the hose very tight, just to support it a bit and dampen any possible oscillation. After priming the oil cooler with fresh, break-in oil, both hoses will be attached to the fittings on the oil cooler adapter plate.

The second photo is a closeup of the somewhat complex mounting screw arrangment for the small angle bracket. The engine comes with an 8-32 tapped hole at this location, which is also being used to secure the top right corner of the oil sump fin cooling plenum. The #8 stainless machine screw is threaded into the tapped hole in the first (right most) fin. However, because the aluminum fin is soft metal in which fine threads may not last forever, the screw is also long enough to extend just enough into the space before the next fin to fit a high temp locking nut. Because of the different metals involved, and the risk of galvanic corrosion, the screw, washers, and threads have all been liberally coated with Tef-GEL anti-corrosion paste. A good hemostat is a big help when placing all these little parts onto the screw in the correct sequence, and tight spaces. The alert reader may notice the small angle is not a structural radiiused angle. Although I don't normally like to use unradiused angle stock, in this case an inside radiused angle would interfere with seating the washers under the screw head a bit, thus forcing the screw hole closer to the edge than it probably should be. As built, the screw hole has good edge distance, the washers have a full bearing surface and perhaps most important, the loads on this part are very light anyway. With this little (2-hr.) bracket completed, the engine is ready for its first oil change -- swapping the factory preservative oil in favor of running break-in oil.

The coarse threaded AeroCarb throttle rod, with nut removed.

Attacked two items that I've been procrastinating about, 'cause they're re-do's and not much fun to boot. The first was the cutting and fitting of a replacement stainless steel heat muff. Alert readers may recall that long ago I jumped the gun by setting the takeoff angles for the SCAT tube outlet pipe stubs before all the other FWF parts and accessories where in place. Cutting slots for the exhaust pipes in stainless is not my favorite job. It actually went a little better this time because I was able to use a "burr" or "cutter" bit mounted in the drill press. The new heat muff has already been sent out for welding of the stainless pipe stubs at their new takeoff angles, which are carefully marked by reference lines, this time taking into account all the other hardware that's now in the vicinity.

The second, related job was to remove the muffler itself and deepen the two dimples on its top that, in a Jabiru-sanctioned fix, were created with a ball peen hammer for clearance between the muffler and the two forward intake manifold bolt heads. The first photo below shows the reinstalled muffler and clearance issue clearly, as does the second closeup shot. There is a flat plate heat shield above the muffler, but it's held in place by the same intake manifold bolts, of course. It's good to finally have these two jobs out of the way. Onward.

Life has been taxing, in more ways than two. Finally got started on cutting and fitting the 3/32" thick blue silicon rubber baffle strips that go between the fiberglass cylinder baffes, the nose bowl. Because I want the forward edge of the baffle strip to describe a smaller circle than the aft edge that's on the cylinder baffe, in the first photo I'm just getting started trying to make a compound shape that can be visualized as two overlapping circles, one higher than the other, with the higher circle having a smaller radius.

Without more time (and ideas) that's not easy to do, but it turns out that it needn't be quite that complex after all. I ended up with an irregular shape, narrower at one end of the strip than the other. To my surprise, because the fore and aft distance the strip needs to cover varies so much, as do the angles coming off the cylinder baffle, that worked quite well. I just rotated my irregular width strip around the fiberglass until it worked, or I should say, will probably work. The photo below shows the test fitting I'll try to go with. The idea is to get the forward edge in a quite regular vertical plane to match the nose bowl, and get adequate and uniform overlap to assure a good connection (epoxy and rivets) to the fiberglass cylinder baffle. In addition to the reference marks drawn on the cylinder baffle that are visible here, the overlap has been drawn onto the cylinder baffle as well. Hopefully, that will allow me to reconstruct this exact positioning with the cylinder baffle taken off the engine.

The unknown factor is how this will line up with the top half of the nose bowl. No way to know except try. The right side, shown here, is a lot easier than the left, where the match up of cylinder baffle to nose bowl inlet is not nearly as close and concentric all the way around as this right side is.

Here's the left cylinder baffle air dam, sitting on top of the engine. Its function is to force incoming cooling air to go to the top of the cylinder heads first, and then pass downward through the cooling fins. Without them, there would be no vertical flow through the cooling fins. Only the first cylinder would get cooling, and even that would be barely adequate. There's a little finish work left to do, but it's a beautiful piece of work, credit for which must go mostly to my generous neighbor, Mike Payne, from whom I am privileged to be learning a bit more about fiberglass. Mike was one of a select few Peugeot Master Mechanics in North America for many years, and is widely known for precision craftsmanship in any material, especially fine paint work. He's now an A&P who works restoring vintage airplanes for the Port Townsend Aero Museum. All of his work, whether in metal, engines, fiberglass, or paint -- to name a few -- is always a joy to see.

We will build 2 or 3 of these air dams for each side from a plug, each one of which will have a different height, or other shaping. As shown in the next photo, they will be attached to the inner baffle circumference with nutplates. A relatively high air dam will be used in cold winter conditions, when the engine needs considerably less cooling air, sometimes a lot less just to keep engine temps hot enough. Because each of the multiple air dams can be shaped quite a bit, they should provide quite a bit of flexibility in tuning up the critical intake end of the engine cooling. This picture also clearly shows the extension made to the oil filter "nook" at the bottom left of the baffle, which will allow the oil filter to be unscrewed and removed from the engine block horizontally -- from underneath after opening the lower left cowl door -- without having to remove the baffle.

Final work continues on the cylinder baffles. In the photo, showing the baffles upside down, the final shape and position of the intake ports has been permanently set by glassing the circle of fiberglass that forms the intake port, to close the original adjustment slit in the intake ports, as they came from Jabiru. On the right is the left cylinder baffle, the bottom of which has a special offset horizontal well or nook, to accomodate the oil filter. As originally built, the nook was right on the oil filter horizontally, tight enough that the filter could not be easily removed without first removing the baffle, which was suboptimal (not good.) Because baffle removal involves a bit of work with the plug wires, which I don't want to do just to change oil, I've moved the position of the oil filter nook roughly 3/4" (to the left, in this photo) to allow room to unscrew and drop the oil filter without having to remove the baffle.

The only items left now on the cowl are 1) right side NACA vent for carb  heat and cabin heat intake, 2) a radiant heat reflector on the inside of the nose bowl near cylinder #1 exhaust, and 3) some minor fairing work on the nose bowl. Wow! Then it will be done!.