Worked on Heater Box and Forward Cover

I clamped some scrap angle with a radius on it to the heater box cover so that I could bend out all of the vents.

This will direct hot air from the engine down into the left and right footwells.

I also needed a notch on the right side to clear the heater box control cable where it passes through one of the firewall stiffeners.

I also cut a notch in the forward cover for the throttle cable.  I’ll clean this up and install a grommet to protect the cable.

Wrapped Up Baffles

With the baffles installed for good, I wanted to wrap up everything that attaches to them.  Here’s the heater air supply duct.  You can also see that I put torque seal on all of the screws that attach the baffles.  I had to remove and reinstall the oil filler tube to get to one of the screws.

I then installed all of the baffle connecting rods.  The rear nut on the left, inner rod was a real pain in the ass with all of the stuff in the way, but I eventually got it.

I hooked up the alternator cooling duct to the bottom of the baffles.

After torquing both ends of the propeller oil line, I reinstalled the support on the bottom of the engine (the shiny clamp on the left here).  I also installed the alternator cooling duct support for good and torqued everything down.

I also reinstalled the butterfly valve and 4″ duct feeding it and hooked up the control cable for good.  I need to order one more worm clamp for the top and this will be done.

Finally, I installed the magneto blast duct to the back of the baffles.  I still need to seal up all of the gaps in the baffles with RTV, but other than that, the baffles are done.

Painted and Prepped Baffles

I stopped by the Tech Shop and used their spray booth to prime and paint the baffles so that they will match the engine mount.  I also primed all of the mounting brackets and the oil cooler butterfly valve components.

After I got home, I used some RTV to seal up all of the gaps where air could leak through and wouldn’t help with engine cooling.

Installed Air Filter Retainer

In order to be able to remove the air filter without removing the snorkel, I trimmed the inboard edge of the ramp back about 1/4″ so that the filter can be lifted and twisted out (as long as all of the surrounding screws are loosened.

I then used a piece of 0.032″ aluminum sheet to fabricate a filter retainer that will get screwed down when the snorkel is screwed to the ramp.  I may trim this back a little further as this is more than long enough to prevent the filter from lifting.

Resumed Work on Baffles and Plenum

I riveted all of the plenum mounting angles to the baffles over the past couple of days then reinstalled them on the engine and drilled the plenum mounting holes out for #8 screws.

I’m installing nutplates that span all of the corners, so I installed them on the outside in order to drill the rivet holes.

After countersinking the holes, I riveted the nutplates on.  I only did the corners while the baffles were mounted on the engine since there is some relative movement when the baffles are off the engine.  I still have to install nutplates on all of the other holes, but that can happen when the baffles come off the engine for the last time.

Secured Mag Wires Along Back of Engine

The right side mag wires were unsupported all the way from the engine mount on the right side to the magneto and were hanging just below the oil filter where they will be in the way during oil changes.  I used a couple of adel clamps to secure the wires to the fitting on the lower oil cooler line to keep them forward of the oil cooler.  This will also keep them from rubbing on anything as they pass under the oil filter.

The wires on the left side and the mixture cable were running against the oil cooler flange, so I needed to secure them to prevent them from rubbing.  The angle is wrong for an adel clamp without using a bracket, so I just used a large tefzel zip tie.  I added a small piece of spiral wrap around the mixture cable to provide a little cushion.

Updated Transponder to Full ADS-B Out Compliance

Included with the SkyView 5.0 software update is an update to the transponder that moves it from TSO C166a to TSO C166b compliance.  This means it’s fully compliant with the 2020 ADS-B mandate for 1090ES.  Installing the software update requires that the transponder be simultaneously labeled to indicate TSO C166b approval.  Apparently, not applying the label renders the transponder unairworthy according to the FAA.

Finished Installing ADS-B Receiver

Jenn came out and helped me rivet the UAT antenna doubler and install the antenna.

I fabricated the antenna cable and installed it.  It routes along the bulkhead and then…

up to the stringer and forward to the receiver.  I also installed the power, ground and serial lines.

Finally, I fired it up and was able to get weather even sitting in my garage.  I only waited long enough to let the regional weather load, but you can see the storms out to the north 100-200 miles away.  You can see in the lower left corner that the regional weather is 4 minutes old and it’s still receiving.  With this done, I’m finished with the avionics (for now at least).

Mounted ADS-B Receiver

I installed the nutplates on the mounting bracket and then put a coat of self-etching primer on it.  I had to fabricate a little spacer to be able to set the LP4-3 rivets since the flange of the stringers prevent the nose of the hand riveter from fitting down flush against the top of the rivet.

I fabricated a small antenna doubler for the UAT antenna, then drilled it to the bottom of the fuselage.  I mounted this 2′ aft of the transponder antenna, just behind the next bulkhead and right on the aircraft centerline.