Engine re-hang, firewall layout

Well, not a ton of shop time today thanks to other stuff going on (including unexpected mower maintenance), but I still got some stuff done. I decided it was high time to move the engine back to the fuselage so I could finalize things like the battery box location. Moving the engine took a bit more time than I expected…but still better than the initial hack getting it bolted to the mount.

The next bit of fun was playing with the battery box. I already knew that I wanted to mount it low on the right side of the firewall, but there were a couple questions still to answer, mainly 1) exactly how low to mount it and 2) whether to orient it with the top of the battery up or sideways. There’s also the consideration of being able to tie the backer plate I’ll be making for the box into the firewall angles.

To make a long story short, I’m going to mount the box sideways. With the top up, the upper left engine mount tubes become problematic for getting the battery in and out, unless the battery either goes so far to the center as to make the backing plate a problem, or so low that tying into the lower angle is also a challenge.

The downside to this position is that the firewall flange will be in the way of removing the battery, which means that I’ll have to loosen the mount bolts to the firewall for battery service. This will be mildly annoying, but not horribly so; with the box so close to the edge, access should be very good here.

The other thing I wanted to verify was the fuel hose routing from the firewall to the mechanical pump. This was to verify that the fittings I had would allow for suitable routing – I was pretty sure I could make it work, but definitely wanted to verify. And I’m happy to say that it looks just fine:

I suppose next steps will be to draw the final location of the battery box, the start looking at where I want to put the master/starter contractors, the battery bus fuse block, and the E-bus relay. Once I get the layout finalized…I get to remove the engine yet again and start working out actual mount hardware and such.

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