Boot Cowl and Instrument Panel Final Install

After numerous fitup iterations (trim, retrim), the boot cowling was painted.  Here is the cowling in the paint booth before priming.

Here is the primed and painted cowl with fine line tape demarcating where the stripe will be located.

Here is masking in preparation of the gray stripe.

Here is the boot cowl painted and riveted to the fuselage.  Overall, pretty happy with the painting results.  Had some run issues on the bottom when it was hanging vertical.  Runs seem more prevalent on second pass.  Seems like 25% reducing of topcoat is optimum.  I applied high temp RTV silicone at the flange forward of the firewall to seal off engine fluid and fume leakage.

The instrument panel is fastened to the boot cowl through a dozen screws with rubber grommets to insulate instruments from vibration.

Avionics and Electrical Wiring Completion and Startup

I can't believe I've finally got a fully functional avionics instrument panel.  I put the juice to the system recently and, instead of sparks flying, all of the components operated beautifully without a hitch.  The biggest surprise was that the combination VHF radio, stick mounted controls and microphone/headphone jacks worked flawlessly: voice-activated intercom, stick-mounted PTT, frequency flip-flop and streaming music from a jack I wired in to play Pandora through my Iphone.  Still need to verify transmission quality.  Lots of micro-soldering work from a complete novice.  The Dynon Skyview required a little configuration identifying the engine sensors and took a little research to get the Garmin 496 to talk to the Skyview, but all works great.  The synthetic vision PFD is awesome.  It is with great relief that this phase of the project is done.  There was no Rans guidance to follow, therefore, independent consultation with component vendors was required.  Following are a collection of install pics over last few months, first off the as-built functioning panel.

Here is the firewall, which shows a blue capacitor I installed to filter engine electrical noise and hence reduce radio noise.  Buss bars nearly full.

I really like the DB connectors, as the crimped pins result in a really solid connection on the wire and snap into the connectors firmly and stay put.  I have used them exclusively in constructing wiring harnesses and in places where quick disconnects are required like near the wing roots where the strobe/nav lights connect.

Front headphone jack and wiring from stick harnessed into DB9 connectors; soldering jacks.  

Music jack

ELT-function tested

Dynon remote compass installed in battery compartment for primary flight display on Skyview

Radio wiring diagram

Constructing radio wiring harness with shielded wire

Transponder wiring diagram

Constructing transponder wiring harness with pins, wire and crimper

Soft start module for ease of starting in cold weather and reduce of strain on Rotax

Electrical Wiring

Been quite awhile since my last post.  I heard a rumor that the electrical part of the project can take the longest, and I'm a believer.  Seems like every operation requires a phone call, as this stuff is just so new.  I started with the battery and worked downstream from there to the starter solenoid.  The engine compartment is completely wired.  I've got the Dynon Skyview engine monitoring module installed and all of the engine sensors wired to the wiring harness provided.  I'm currently working on wiring the gps and transponder to the Dynon display.  Here are some pics of the mess of wiring...

Rotax Carb Mechanical Synch

I adjusted each carb so that each has the same power setting at high and low throttle.  This is important because each carb independently operates 2 cylinders and, if not in synch, excessive vibration will occur.  Procedure:  Advance throttle levers to full, then back off so that you can insert a snug feeler gage into one, then adjust ferrule on the other throttle cable such that the same feeler gage is snug.  Next pull throttle all the way back to idle.  Ensure that at the idle stop, no gap exists between carbs.  If so, adjust idle screw so that they are the same with no gap. 

I've got them set and will go with these settings at start up.  If excessive idle, I will back off each idle screw same amount, e.g. 1/4 turn.  If vibration still occurs, there is a way to synch carbs pneumatically by hooking up pressure gage and making sure differential pressures in intake manifolds are the same. 

Rotax Engine Mod: 2000 TBO

Found service bulletin SB-912-057UL for the engine which increases the time between overhaul (TBO) from 1,500 hours to 2,000 hours.  All it entailed was switching out an oil pump plug screw and pressure spring.  A metal ball was reused.  Following are some pics.  New unit on right. 

Control Cables Install: Throttle, Parking Brake

Here is a pic of all of the push-pull knob control cables installed.  Still have to finish up the choke cable.

 

Next pic shows the control cables behind the instrument panel.

Next pic shows the throttle control cables installed to the throttle lever.  Set screws were loctited into the lever to hold the cables.

Here is the throttle cable installed to the throttle lever on the carb.

Finally, here is the control cable configured to the parking brake assembly...

Fuel System Install: Firewall Forward

The fuel system is complete forward of the firewall.  The pics below are sequenced in the order that the fuel flows.  The first component installed was the gascolator, which acts as a fuel sediment trap and screen.  The fuel flows into the bowl from the top elbow and then out through a screen near the top and out through an elbow on the other side.   Note the spring-loaded valve on the bottom.  The unit is mounted on the firewall.

The auxiliary electric fuel pump is mounted on cushioned clamps to the engine mount.  I'm told it's a diaphragm type pump which offers little restriction to flow when not used.  Note the black fuel lines housed within firesleeve.  The firesleeve is capable of withstanding direct flame for up to 15 minutes.  The fit was snug between fuel line and sleeve, so I clamped both hose/sleeve via single clamp to the hose-barb fittings.

Next component installed was an in-line fuel flow sensor from Dynon.  This was installed where a fuel filter would normally go; however, I did not install the filter based on recommendation from Rans that there are issues with it being compromised by ethanol fuel additive.  First pic looking down and then up.

Next a connection is made at the rotax supplied line...

...And the that line runs to the mechanical fuel pump.  First an overview shot and pump housing closeup...

From here fuel is pumped to the bottom of the banjo junction fitting, mounted on the compensating tube.  Following pic also shows return line on top running to the gascolator.  A fuel pressure sensor from Dynon was installed where a plug was located in the fitting.  Rans indicated their supplied sensor has been shown to be erratic. 

Here is view from top, which also show the smaller two lines running left and right to each carb.

ADDENDUM:  After talking to Rans and spending several days in deliberation, I decided to redo all of the fuel line connections and clamp the fuel lines directly to the hose barb fittings.  I then safety wired the fire sleeve to the fuel lines.   Here is a pic showing the revised fuel lines in the firewall area.

ADDENDUM 2:

After further investigation and, yes deliberation, I ended up sealing the ends of all of the fuel line firesleeve with RTK high temperature silicone.  Ed at Rans had a great tip to use Formula 409 on your fingers.  This allowed you to form the silicone without it sticking to your fingers.   I've got these lines as fireproof as I'll ever get them now.