AeroInjector and Throttle/Mixture Cables (3)

3 hours

I wanted to get the throttle and mixture cables figured out, since they have to penetrate the firewall and they aren't super flexible, so I didn't want to inadvertently install something that would be in their way.

The first thing was to source parts.  After some research I ended up ordering this mixture control from Aircraft Spruce:  https://www.aircraftspruce.com/catalog/appages/a7902.php

It's probably overkill for this plane, but I wanted a vernier knob and this one seems pretty nice.  I ordered the 72" length, and only ended up cutting off like a foot, so I recommend that length.

For firewall penetrations, I bought two of these cable fittings:  https://www.aircraftspruce.com/catalog/appages/cablesafe.php

They have a 1/4" ID, which fit the ACS mixture cable perfectly.  The stock AeroConversions throttle cable is a hair larger than 1/4" though.  I carefully drilled one of the fittings a tiny bit larger to fit the throttle cable, and it seems to have worked fine.

I installed the mixture control in the stock location on the left panel support bracket.  I updrilled the pre-drilled hole to the appropriate size and then installed the control housing.  The only issue with this stock location is that the bracket is a little small for this knob.  I ended up having to omit the lockwasher that came with it, and file a little bit of a chamfer on one edge of the nut so it would fit.  It might have been worth trying to drill a new hole in a different place, but I think this will work.

I located my two firewall penetrations in the upper left corner of the firewall, to give both cables as straight of a shot as possible through the fittings.

The next step was to install the throttle cable into the AeroInjector.  You have to disassemble it to install the cable, and then it just snaps in to the throttle plate.  Then I put everything back together and fed the cable back through its housing to the throttle lever.

To make a nice angle for the two cables, I installed the injector on a slight angle to the cables enter it from the front right.

Next I connected the mixture cable.  This gave me some trouble at first, because the instructions have you route the cable end through a swivel nut and then tighten the nut.  It's supposed to be tight enough to hold the cable tightly, and still allow the swivel nut to rotate within the swivel arm.  I found that tightening it at all clamped the cable against the arm, so it couldn't rotate!

I ended up buying a set screw from Home Depot, running a tap through the swivel nut so the whole length was threaded, and then installing the set screw from the opposite side.  The set screw pushed the cable away from the arm, so when I tightened the original screw it held the cable securely without locking it against the arm.  That worked well and now it moves nice and freely!

Here's my overall cable routing:

Tank Re-Installation (1)

1 hour

I want to install the throttle and mixture cables next, but I need the throttles out of the way to get the tank in and out.  I'm 99% sure I'm done riveting things to the upper firewall, so I went ahead and put the tank back in so I could reinstall the throttles.

I'm glad I did end up having to pull the tank, because while carrying it around I noticed a bunch of debris rattling around inside.  After some investigation, I discovered that the brass plug I had installed in the large fuel supply fitting (just to keep dust and stuff out) had corroded the aluminum fitting and created a bunch of flaky deposits.  I removed the bulkhead fitting and ordered a new one to replace it, and then gave the tank a real good flush with the garden hose.  Finally, before I re-installed the tank (hopefully for good), I put a few pieces of teflon anti-chafe tape along the upper front edge, where it's very close to the firewall.  Then I put it back in the plane!

Spark Plugs Wires (1)

1 hour

Next thing was the spark plug wires.  The four upper plugs are all powered by the magnetos via their built-in wires.  I routed each one through a grommet in the baffle.  The two rear ones go through the baffle all the way in the outboard corners, through pre-drilled holes.  I drilled my own holes for the forward ones.

The lower plugs are powered by the coils, which I haven't installed yet.  I popped the boots over the plugs, but I'm not sure exactly how I'm going to route the wires yet, or where I'll even mount the coils.  So I'll finish them later.

CHT Sensors (0.5)

0.5 hours

I bought 4x CHT thermocouples from Sonex when I ordered the engine.  Installation is pretty simple, you just drill a #32 hole next to each spark plug, and then screw down each ring terminal using the included self-tapping screws.  Here you can see where I installed them, and the other side is the same.  Luckily you can still access this area with the intake installed!

Oil Separator Connections (1)

1 hour

I got some more little hose fittings in the mail so I was able to run the lines to and from the oil separator.  The input is just a hose connected to the breather port on top of the engine.  The output is a braided hose that goes from the bottom of the separator back to the oil sump.  This one is important because if it leaks all the oil will leak out of the engine!

Exhaust Wrap and EGT Probes (2.5)

2.5 hours

Next thing was to wrap the exhaust and install the EGT probes.  I drilled a hole for each probe 4" from each exhaust flange along the center of each pipe, according to the Sonex instructions.  I'm using Dynon probes, which is not exactly what Garmin recommends, but they're a lot cheaper so we'll see how they hold up.  I found that a #29 drill was the right size for these probes.

Once I had a hole drilled in each tube I went ahead and wrapped the whole exhaust.  I did the short tubes for cylinders 1 and 3 first, starting at the bottom and working toward the heads.  Then I did the tube that runs across the back of the engine up to cylinder 2.  Finally, I wrapped from the turbo all the way to #4.  I used a bunch of temporary zipties to hold everything in place as I went, and then finally a hose clamp at each end of each run once it was all wrapped.

To install the probes through the wrap, I marked where each hole was as I was wrapping, and then went back and poked around with a straight pick until I found the hole.  Then I was able to easily get the probe through the wrap and into the hole.

The 50-foot roll of wrap that came with the engine ended up being just enough to do the whole exhaust manifold plus the 2-piece turbo exhaust.  I'll probably redo the lower detachable pipe later once I see exactly where it crosses the cowl, since I won't want any wrap hanging out in beyond that.  Plus I ran out of hose clamps anyway.

Oil Separator and More Coolant Lines (3)

3 hours

Continuing on with getting the major things mounted on the firewall, next I mounted the oil separator just outboard of the radiator on the engine mount.  I used two adel clamps on top and one at the bottom.  I'm still waiting for a couple of parts before I can make the oil return hose that'll run from the bottom of this can to the oil sump on the engine, so I'll do that later.

I also ran the long coolant line from the radiator outlet to the pump inlet.  I ran it down the firewall and ziptied it to the intake tube and then the engine mount right in front of the pump.  Again, I think I will replace these zipties with something more durable before I call it done.  This used up all that was left of the hose that came with the radiator, so I'll just need to buy a little more to connect the coolant bottle to the radiator inlet.

Turbo Cooler Radiator (8)

8 hours

The next large items I needed to find space for near the firewall was the radiator and coolant bottle for the turbo cooling system.  Sonex provides a plan for cutting out and bending a little radiator plenum, which I found to actually fit pretty much perfectly.  I made it out of a chunk of scrap sheet I had from ages ago.

Next I had to figure out where and how to mount it.  There are some pictures at the bottom of the page here that I used for reference: https://www.sonexaircraft.com/aeroveeturbo_update_020618/

I ended up for the most part copying what Sonex did.  I made a piece for each end of the radiator out of 1"x1" angle, and then some small brackets out of 2"x2" angle, cut into various shapes and sizes.  The brackets on the aft side will be riveted to the firewall, and the brackets on the forward side will be attached to the engine mount with adel clamps.  I also used another piece of 2" angle to create a mounting point for the coolant bottle.  It took quite a bit of trial and error to get the geometry of each bracket figured out, but eventually I think I came to a good solution.

I put the bottle at a slight angle to help it fit between the intake side of the turbo and the cowl.

I riveted the brackets from the inside to avoid possibly interfering with the gas tank.

The manifold pressure transducer was going to interfere with one of the coolant lines to the radiator, so I installed a 90-degree street elbow to get it out of the way.

The run from the turbo coolant outlet to the bottle inlet is really short so I had to bend the hose barb on the bottle out slightly to make it fit without kinking the hose.

Oil Lines & Firewall Stuff (5)

5 hours

I needed a break from working on the baffle, so I started working on the various external oil and coolant lines next.

The first one I made was the long AN6 hose that returns oil from the bottom of the turbo back to the oil pump.

I used this silicon fusion tape to provide some abrasion resistance wherever the hose would touch the engine mount or anything else.

For now I ziptied the hose to the bottom of the engine.  I'm not sure if that's sturdy enough, so maybe I'll attach it with something more substantial later.

Next I formed the little AN4 hard line that goes from the case, aft to a bulkhead on the baffle.

An AN6 hard line will connect these two fittings, but I'll wait until the front area of the baffle is finalized before making that one.

    

Anyway from that bulkhead on the baffle, an AN4 hose goes to the oil filter, and then another one from the filter to the top of the turbo.

Once I had a spot staked out on the firewall for the oil filter, I figured I might as well place the coolant pump as well.  The short pieces of blue hose are 1/2" ID silicone heater hose as called for in the plans.  The barbs on the pump are actually 5/8", but the silicone is flexible enough that it still fits so I could still use the 1/2" to 3/8" adapters I had already bought.

The output from the coolant pump connects to the back side of the turbo.