Red Cube HOBBS 1617.0 hrs

Ok guys and gals, I'm back! I have bit the bullet and bought the added storage capacity. I think I will start my own website once the plane is finished to document my ongoing adventures flying Wablosa. At that point in time, I will just leave this build site up as an inactive archive of the build process. But until then, I needed to purchase this storage to keep it active and keep on trucking!

 

Turkey day was wonderful, hopefully you all had a good time with family/friends and ate some good grub! I put in a strong week in the factory over the holiday weekend...not great, but strong...pushing me to 1617.0 hrs on the HOBBS. I am hoping with my month long holiday break from school in Dec/Jan to be knocking on the door of the 1700 hr threshold by the first week of the new year.

 

If you remember back to my post when I received my engine and its contents, I didn't know what this wiring harness was for? Well, turns out it attaches to my Plane Power 60A alternator...mystery solved with a little help from the Internet and my trusty iPhone I was able to confirm this....technology is great. I will hook this up soon now that I know what it is.

Adding a wire from the ANL current limiter up to the battery.

Starting to lay out my Aveo switches for wiring. This is the lineup I am looking for to occupy the ten switch locations on my Aerosport carbon fiber panel. I will probably add a couple more (boost pump, pitot heat) but they will be mounted in my center console. Again, notice, I am following the Vertical Power pinout chart....so handy!

Here I have started to add wires to the connector for the switches. This connector (cant remember if its J1 or J2?) will plug directly into the Vertical Power box.

Cant have power without ground...in this pic, you can see I am doing my ground wires for the switches. These will all go to my "forest of tabs" ground block on the firewall. Even though it is just a common ground, I am still labeling it. If I have to troubleshoot any wiring later...I want my ground wires labeled as well. Some will argue its not important, a ground is a ground...I disagree, there could be good reasons for knowing exactly "which" ground you are dealing with...i.e., intermittent connections, ground loops, etc.

After agonizing for what seemed like forever...actually I think it was months...I finally made a decision for my fuel flow transducer, aka the "red cube". I was considering a few options. #1, mount it after the boost pump in the cockpit. #2, mount it downstream from the fuel injection servo and before the distribution spider...or #3, after the mechanical fuel pump on the firewall. They all had pluses and minuses. This location is what I settled on, it is option #3. I think it is a good compromise.

Here is my info dump of each option listed above from my research on this pesky little red cube. I advise you start thinking about this ahead of time and come up with a plan.

1. Pros: Inside the cockpit, less potential for fire. It is recommended to firesleeve the cube if it is mounted FWF. It is an aluminum cube, alum doesn't play well with hot FWF fires. Cons: reports are that your fuel flow readings will spike while the boost pump is on. The mfg recommendations say to put it downstream from both the boost pump and the engine driven fuel pump. This was my first choice...most feedback from other builders is that the spike is hardly noticeable. Even though ultimately I didn't go this route, I wouldn't have a problem with this mounting strategy...I think a lot of the RV10 guys put it here.
2. Pros: This is technically where they recommend you put it...after both pumps and the servo. Many builders go this route with good results. Cons: With a crossover exhaust, the space is limited and the location puts the cube in close proximity to my hot exhaust, which they don't recommend...and I didn't feel good about either. Hot fuel and vapor lock is constantly in the back of my mind as I plan fuel flow routing FWF. This was a location I preferred and consumed a lot of brain cells thinking about. I looked and looked and played around with many different mounting schemes to try and come up with something I felt comfortable with...and I never got there.
3. Pros: Downstream of both fuel pumps, mounted on the firewall so there will be no engine vibration imparted on the cube, and easy access for maintenance/mounting. Cons: Its mounted FWF, which isn't ideal in my mind, I still don't like the idea of putting this puppy in the engine compartment but its a risk I am willing to accept in the event of a fire. At this time, I don't plan to wrap it in firesleeve.

 

Lastly, now that you've seen my mounting location...let me add, DON'T mount it with this ORIENTATION!! After I made my nice little bracket and got it mounted, and really felt good about my decision, I noticed I mounted it BACKWARDS! The flow direction is wrong in this pic...I need to make a new bracket and flip it around 180 degs. D'oh!! Mistakes will happen...just glad I caught it now, rather than later.