Tank Calibration and Transfer Pump (Aux to Main tanks)

I had not calibrated my tanks in a level attitude.  As a stop gap I put the same cal values from a tail low attitide into the level attitude column.  I needed to find a way to have the aircraft stable while doing the calibration... it takes awhile.

Qty 3 2x4's, and a cheap boat winch.

Calibration done, except the right aux tank.  The transfer pump died.  New one ordered (plus a spare).

This is when everything went wrong.  I took the pump out, verified it was dead and went to put it back in so I could fly.  Somehow I cross threaded the Swagelok fittings.  I tried to repair the threads, and was successful EXCEPT on the fuel line side.  Can't get it off.  So had to change out the right wing to flex hose.  Now everything is just standard AN fittings.

Now I have to do the left wing one day... not a hard change when required.

Header tank, venting, flow, low fuel levels

The header tank - and more specifically the header tank level indication - have been giving me problems.

On the first flight, the header tank warning went off.  Landed quickly, and tore the entire system apart and made it better.  

4 hours of trouble free flying after that.

Then the low fuel header warning started going off again - but it always cleared, usually within 30 to 60 seconds.

I am not going to live with this, so investigation into why.

I know the fuel system can keep up with the demands of the engine.

Through a bunch of smart fellas on the forum and fellow UL builders, we have been scratching our heads.

The suggestion came up to look for something on the suction side that is tight enough to not leak, but not tight enough to not let air into the pump / injectors.  He also suggested del rings (available at spruce) that provide a better seal on AN fittings.  But then I found it.

On the input to the pumps, the clamps were not tight.  And the hose barb fittings on the other side of the hose had no clamps.

Before

After:

Time will tell if this solves the problem... but the current working theory is air was coming in through the return line into the header.  The air would build up, and it would take time for there to be enough pressure for the air to make its way up the vent and 'burp' the tank.  Then everything would be fine for awhile.

Header tanks are a real head scratcher in their design, specifically the vents (in high wing aircraft).  I think I am slowly ironing out the kinks.

Update:  This did not solve the problem, and now the problem is worse.  I started putting some pieces of the puzzle together a few days ago.

I started of running ethanol free 89 octane fuel, and used boostane to bring it up to 94 octane.  Around hour 5, I switched to ethanol 94 octane, which I can get locally (have to go to Blaine, WA for ethanol free).  The problems started (again) when I switched fuels.  I did not put these two things together until about hour 19.

So the problem started again after switching to ethanol fuel, and it has been getting worse the as the outside air temps have risen.

I started googling 'ethanol fuel', 'injection systems', and 'header tank'.

And then add this (below) from the UL installation manual.

What I make from all this.

• I had 5 trouble free hours running non-ethanol fuel
• My header tank design had a flaw, in that my return was on the top of the tank.
• Ethanol fuel is more prone to frothing
• I've been having more problems since the weather started warming.

I now have a tube / stand pipe for the return that is 5" below the top of the tank.

This should fix or at least help the frothing problem.  I may be dealing with vapour as well.

The vents are capable of clearing the air... it's been doing that for 14 hours of issues.

I have replaced a section of the vent line on the A pillar with translucent tubing.

The hope is I will be able to see bubbles.  I plan on having a camera face the vent tube to capture what is going on.

I am going to go back to ethanol free fuel.  I may start off with a 2/3'rds mix as I have to get rid of the ethanol 94.  1 part ethanol, 2 parts non ethanol.

Cameras on the panel and the vent tube.

Ground run first to shake out any issues.  If that is successful, will stay over the airport for at least an hour to shake it out more. 

So fast forward months... 

I've upgraded the vent line to a 6 mm ID all the way out to the wing tips.

I moved the header vent line to be AFTER the check valve (not before).

The problem is virtually gone... it will happen every once in awhile, and you need to drop a wing and go into uncoordinated flight for 30 seconds to get the bubbles moving from the header up to the tips.  Seems to happen about every 2 hours of flight.

I think I have a bit of a P trap in a climb... but it doesnt always happen in a climb.  So I dont know.  Its FAR FAR FAR better than it was.

Fuel system changes, and second test flight.

It's been 9 days since the first flight.  Been working to understand the header tank issue so I can fix it.

First was to essentially redo the fuel flow test to understand if the vents are working properly and fuel / air can move where they need to move.

For the first flight the header tank venting system went like so:

• From the header tank, two vent lines come out of the top and run horizontally towards each wing.
• Make a 90 and head aft and go up the door frame.  From there they go along the top of the door to the wing hinge just forward of the aft spar.
• Then they make 180 and go forward and are attached to the root rib.  They transition around the forward spar and then into a conduit along the leading edge of the wing.
• They exit the leading edge at the tip and are T'ed into the vents from the main and aux tanks.  
• Then into a Andair checkvalve, then to the JD airparts vent under the wing.

The problem with this... the big U from the door back to the leading edge could be a P trap.  I did it this way so you can still easily fold the wings.

So I changed all this.  The vent now exits the fuselage at the leading edge of the wing and goes straight down the leading edge.  It is now always uphill to the wingtip.  All of this was accomplished in a couple hours.

Then to test...

Ran many, many tests.  The summary of what I found.  

1. The fuel flow with the original and new vent configuration is the same.  
2. The right wing was transferring fuel averaging 30% slower than the left.
3. I separated the vents at every point possible and redid the test.  Was always within a couple percent of each other.

The focus then became why is the right wing transfering fuel slower?  It wasnt the vent.

• Folded the wings (again).  Took out the finger strainers.  Strainers were clean, but there was construction debris (what my friend Geoff calls 'sworf').  Cleaned.  Tested again, no change.
• Focused on the areas between the wing root and fuel selector.  Drained the lines, took every fitting apart and checked.  Found some shitty pipe ends that needed some filing.  
• Removed the fuel valve.  Tested from the wing to the input of the fuel valve.  Both sides where identical.
• Did a flow test on the fuel selector.  Same on both sides.
• The lines from the wing to the fuel selector are 3/8".  The output of the fuel selector to the header tank was also 3/8".  No bueno.  I had the right fittings to change that to 1/2".  Header tank removed.  Drilled and retapped the tank (luckily the boss was HUGE).  New 1/2" fitting on the header tank.
• Reassembled EVERYTHING and tested.  Now the flow is within 5% of each other.  On BOTH the fuel flow is considerably faster.

I tried to find fittings for the header vent at the wing / fuselage intersection.  Everything I tried leaked.  Finally just put in a short hose coupler with some clamps.  No leak.

Slept... tested again in the morning.  Still good.  Put the rest of the interior back in, wingtips back on, cowlings on.  Time to fly.

So I repeated the first flight.  Overhead the airport.

On the first test flight the header tank warning went off 26 min into the flight running at 13 GPH, 1500 feet.  So i did that again, but for 45 minutes.  Rock solid.  For the next 15 minutes I played with different power settings from 5 GPH to 15 GPH.  Still solid.  Landed without incident.  Airplane and pilot reusable.  Success!

No crowds this time.  No fanfare.  Just me and the Sportsman.

I put 40 lbs of stuff in the back and tied it down.  Move the CofG aft a bit.

Takeoff was great.  Climbed very quickly.  Setup an orbit at 1500 ft.  No alarms... only green LED's.

So that was flight test #1 repeat.  No audio issues.  My landing still sucked :-).

Assembly... ongoing.

Big day today (Tue, Oct 14).  Was laid off today, AND got my wings back on the Sportsman!

Such a great bunch of folks at Langley Regional Airport.  8 people showed up to help. 35 min start to finish.

And my friend flew his RV6A today for the first time.

Now I have clear runway for a TON of stuff to get done.

Fuel sender wiring underway, fuel lines connected, fuel filler necks installed, and antenna installed.

Crossover cables connected, but not yet tensioned.

Wing umbilicals fed through and connected.  Cleaned up the wiring for the inboard tank sensors.

First landing / taxi light installed.  Just need to put the pins in the connector (once I remember how I wired it... luckily I have documentation).

4 outboard strut attach bolts installed and torqued.  Total pain in the rear.  Using the clevis bolts inboard for tie down points.

Progress is so slow.... life is getting in the way - but I have a bunch of stuff I can work on.

Inboard delta wings installed.

Plan is the install the pins in the forward spar for good!

Flaps are connected.  Need to tweak the tension a bit, but everything works well.

Ailerons next.

Forward spar pins installed!

Lights attached and wired.

Pilot side door getting its final silpruf.

Spinner!

Lots more to come...

Fuel Tank Vents

This tasks has been on my mind for literally years.  Modifying a fuel system scares the crap out of me... 

I have a header tank... purpose of the header is to simplify the fuel system.  Fuel injection return can simply go back to the header and does not have to go all the way to the main tanks.  Can also use a simplex fuel valve, and not a duplex.  Also adds some weight up front, and 2 more gallons of fuel.

So the vents... per the manual, run the vents out the bottom of the wingtip using either aluminum tube or the plastic line.  It is well known that this vent system will leak when (1) the tanks are full, (2) parked on a slope, or (3) daytime heating when the tanks are full.

The TWTT instructions modify the vents from the original manual.  The vents are T'ed together, and you run the vent line up as high as possible under the tip.  This is better.

On the forum, many have modified the vents using a 'bleed' type check valve prior to exit.  Lets lots of air in, only lets a little bit of air out.

Lastly, the underwing / tip exit has caught many on the noggin.  The aluminum tube vent is the worst.  Some builders are now using under wing machined aluminum vents designed for RV's.  These are nice as they have a screen, 2 vent holes (1 facing forward, and a backup at the rear).

Link to JD Airparts Site Here.

So my plan is to incorporate ALL of these.  T the vents, check valve, and under wing machined vents.

My worry... the vent for the main tanks and header tank work OPPOSITE from a venting persepective.

For the main and aux tanks, the vents let air in so fuel can depart.  For the header, the vent lets air out so the header can fill.  I'm worried they will fight each other... but we will see very soon I hope.

The bleed type check valve is key.  It definitely lets some air in.

On the flip side... the pumps will create some suction and draw fuel through (I hope).

I mocked one vent assembly up last night.  Everything fits under the wingtip.

I used a 1/8" NPT male / male into the tank.  A 1/8" NPT 'T", then a 1/8" NPT to AN4 female for the check valve, and a 1/8" NPT hose barb on the other end. Going to feed the nylon line into 14" hose and clamp it to transition from the vent line to the "T".

First one (left wing) complete.

Was somewhat worried about edge clearances on the -4 fitting that holds the vent to the bottom skin.  May reinforce it... will see.

(The wings are folded currently...)

I reversed the direction of the check valve... what is shown in the picture is backwards!  That would have been disastrous...

Fuel system delivery testing and results

Spent Saturday, March 1 2025 testing the fuel system.

Bottom line:  Good new, and news.  The news is yet to be determined if good or bad.

Needs:

• Everything is going to be in Liters.  It’s just easier.
• Then UL520T needs 68 Liters / hours (based on 0.3 Liters / hour / HP)
• Using a 50% safety factor.  Gravity system needs to deliver 102 liters / hours

Test setup

• Fuel system emptied of all fuel, except anything unusable (specifically header tank).
• 20 liters added to each main wing tank
• Check valves installed in header tank vent, with directional arrows pointing away from the header

Header fill

• Took just shy of 6 min to fill header tank.

Test 1

• Drained 20 Liters into Jerry can at firewall, same level as exit.
• Fuel selector on BOTH
• Gravity only.  Tailwheel on the ground.
• Time:  8.8 min, which equals 136 Liters / hours.
• Pass (102 Liters / hour needed)

Test 2

• Drained 20 Liters into Jerry can at firewall, same as test 1
• 20 Liters added to left tank
• Fuel selector on LEFT.
• Gravity only, Tailwheel on the ground
• Time:  11.2 min.  107 liters per hour.
• Pass

Test 3

• Completely drain useable fuel from header
• Add fuel to both tanks.
• Test fuel consumption with header low
• Upon setting up for this test, with fuel selector OFF, header tank would not drain.  This is due to the check valves blocking the vent path.
• Test fail.  
• Not sure if this is a bad thing or not.

Test 4

• Repeat of test 1
• 8.7 min, 138 liters / hours
• Pass

Test 5

• Fuel selector on both
• Fuel pumps connected to firewall bulkhead connector
• Fuel line from engine disconnected.  Fuel pumped from gascolator into Jerry can.
• 20 liters pumped
• 4.92 minutes, 244 liters / hour
• Pass
• This is an unreasonable test.  The header low warning lights came on… the first one at 2/3rds came on after 1.76 min.  The 2nd one came on after 3.73 min.  There is no scenario where this would be needed… I wanted to see where the header tank could not keep up with the demand, and I found it.
• It took 6.6 min for the header to fill back up after the pump was shut off.

So what did I learn from all this:

• The check valves on the header tank solve the problem of fuel coming in via the vents.  This also solves the cross feed problem.
• The header tank fills slower than I would like.
• In no reasonable scenario tested did the header ever show a warning.
• Even on 1 tank, there is enough fuel delivery for full power fuel consumption plus a 50% safety factor.
• All my tests were with a maximum of 20 liters / 5 gallons in each tank.  This test needs to be performed with FULL main tanks (60 liters per side).  This should add significantly more head pressure.

More testing needed, but so far the system works.  Need to change some variables and test again.

Header tank venting...

Well, I have backed myself into a corner.

Further to the last post about the header tank vent(s)... current design (T'ed into the vent for the pillar header and to each main tank) is not going to work.  This will lead to cross feed and an ineffective fuel valve.

What are the 'truths'.  Things that I know are facts:

1. The header needs to be vented to allow air out so there is room for fuel to enter
2. The vent point should be higher than the highest fuel level
3. The current configuration will allow bypassing of the fuel valve, and cross feed on the tanks

Options:

1. Check valves on the header vent between the pillar header and the main header.  This will stop fuel from the main tank / pillar header from each side entering the header.  It will allow air to escape IF the air pressure is greater than the head pressure from the fuel.
2. Mast vent on the center line with the exit above the wing level.  This presents an opportunity for fuel siphoning out the vent.  No bueno.
3. Using Paul's method run a new vent line out to one wing tip.  This is problematic, but doable.  In theory this solves all problems.

Option 1 is easy and cheap to try.

Option 2 scares me

Option 3 is more work but most likely the best solution.

4th option:  Modification on option 3... run a vent line out and T into the outboard vent on the main tank.  This is more doable, but assumes I have access through the forward spar to fish the new vent line through and T it in.  Need to look at old pictures to see if this is possible.

Yesterday (February 22) I installed a check valve on the starboard header vent.  Aircraft spruce check valve that has no spring, gravity only.  Arrow points towards the main tank to let the air out.  I was going to install the port side, and realized I only ordered enough fittings for one side (ordered 2, needed 4).  So those are now ordered.

Prior to installing, I wanted to get the fuel out of the vent lines.  After grounding the aircraft and draining all the fuel from the belly low points and header, closed the main fuel selector to OFF, and pushed compressed air into the header from the firewall fuel line fitting.  That did the trick... when cutting the vent line, there was no fuel.  WIN!

Now waiting for the other fittings to arrive to do the starboard side.

I am very concerned about fuel delivery.  This needs to work and work well.  No compromises here.

2nd check valve installed (Feb 28).  Fuel ready to go in the tanks... first will be a leak check, and then a fuel delivery check.  See how much I can actually deliver.

I am getting more stoked / positive on option 1.  In theory, when the pumps are drawing fuel from the header, it will create suction... which will pull the check valves closed... and actually draw fuel faster.  At least that is my theory.  Will see if it holds true.  Stay tuned...

More Progress... some frustrating, some not...

Well, the progress keeps coming... slowly.

Loaded all the UL520T parameters into the EFIS today.  Not hard.

Downloaded the checklist file... that will be left for cold days to come.  The checklist will be interesting... looking forward to that.

Brake leak appears to be fixed... but ANOTHER fuel leak.  Traced it to the fuel selector.  Everything cleaned, now waiting to see if it reappears.  I fixed it late morning, and there was nothing by dinner time... 

Lots of visitors today... lots of airplane talk.

Then I decided to tackle the hatch covers.  Watching the videos, those just need to get done.  I have had a mental block on these... I started fitting the port side cover ages ago, became frustrated and left them.  More frustration today... they just do not want to fit nicely.  Call to Zach in order for tomorrow morning.

Looking at the forum, this sounds like a common issue...

Post First Engine Start - Review

The day after the first engine start I took a detailed look at everything firewall forward to see what I could see.  Overall, results were positive.

• Slight fuel leak on the banjo fittings going into the pre filters (before the fuel pumps).  This leak has soaked the firesleeve on the line between the inlet and the firewall.  Will replace that firesleeve.
• Everything prop related looks good.  Nothing untoward on the slip ring.
• No chaffing on any wires
• 3D printed inlets attached to the plenum show no signs of heat distortion.
• Exhaust looks good
• The engine puked its preservative.  This primarily came out of the slip joints on the exhaust and appears easily cleanable.
• Oil level is good, and no discolouration at all.
• Oil cooler appears good
• Overall, everything survived AOK.
• Downloaded the logs from the EFIS and loaded into Savvy.  EGT's 2, 3, 5 and 6 show 0.  Need to check configuration and/or wiring connections.  CHT's 3 and 5 also show 0.  Same check.
• Note:  Advanced has added functionality that every engine parameter can be picked up off the CANBUS or discrete sensors.  Everything in my configuration is coming off the CANBUS EXCEPT the EGT's and CHT's.  I may have not flipped the ones showing 0 to discrete sensors through the EMS.
• Talked to Tracy who has the same engine / prop and is flying.  He noted my MP is higher than his.  I had some of his logs and checked, and yes - about 2" higher.  But it was far colder (density altitude -980 feet the day the engine was fired) and very close to sea level.  This is something to watch.
• Fuel flow at idle 1.6 GPH.  Fuel flow at 1500 RPM 4.1 GPH.
• Weeping at the fuel drains on the main tanks.  Not surprised as I did not seal them as they are coming out for paint.
• The header tank has 2 ultrasonic sensors to show fuel level.  The 1/3rd sensor warning goes off when the pumps are running.  Guessing this is due to turbulence at the tank due to suction from the pumps.  The 2/3rds is rock solid.  Tested this with the engine not running and behavior is the same as when the engine is running.
• Fuel pressure consistent in the mid 30's.
• I have two current sensors.  One shunt that shows everything to / from the batteries, and one on the engine bus (hall effect sensor).  At idle, the engine bus (ECU, coils, pumps, etc) was pulling 9 amps.  At 1500 RPM, 11 amps.

Overall, the only thing that needs to be 'fixed' is the leak, and the problematic EGT's and CHT's.

Getting ready to awaken the beast...

Getting ready to start the engine.  So today was all of the little things leading up to that.

Checked all the fuel fittings, then put fuel in one side to test fuel delivery to the header.  I forgot to tighten up the banjo fittings on the fuel selector, so it pissed fuel all inside the fuselage.  Took me a minute to get it tightened once I realized where it was leaking.

But the big problem...  The fuel selector was in the OFF position, and I could hear fuel going into the header.  I immediately thought it was a problem with the selector.  After some head scratching, we pinched the fuel vent line, and it stopped.

I have the pillar headers, which are vented to the mains.  I T'ed the vent off the pillars and ran down to the firewall header.  Fuel is going into the header via the vents.

In hindsight, this makes perfect sense.  But this is not a flyable configuration.

My first thought is to put a check valve on the vent line between the pillar header T and the firewall header.  But I don't think this is ideal either.

But it is a place to start, and I will learn something.

We did accomplish cleaning out any 'sworth' in the tanks, which was minimal.  Inboards only.  Will do the outboards another day.

Next is to come up with a plan to correct the vent situation.  In parallel pressurize the engine fuel system and check for leaks.  I can start it with the vents as is.

Wing to Fuselage Fuel Lines

The whole purpose in folding the wings (and getting the folding mechanism complete) is to get teh fuel lines from the wing tanks to the pillar header.

Installed the fittings in the wing tanks last night.  For some reason I have had this block... Did not want to cut the fuselage, and just wasnt sure how it would all go together.  Well after really looking at it, its pretty simple.

My only complication is I need to tie the header vents into the wing vents.  I hope this does not bite me in the ass (it WON'T - being positive... it WILL do the job).

Port side cut last night.  Need help on the weekend to fold the wings and check clearance.  I measured everything, so it should be fine.  No, it WILL be fine :-)

Port side fuel and vent connected temporarily.  No clamps yet.  Used a T just above the pillar header to connect the header tank vent.  Next is to swing the wing and see what happens.  Fingers crossed.

Well, had to remake all the fuel lines... they were all to short when unfolding the wings.  Finally got them right.  Working in the space above the header tank is a royal pain in the ass.  The left side is all clamped, still need to do the right side.  Waiting for a TEE fitting which will arrive on Tuesday.

Port side done...

Fuel lines done... now to unfold the wings and start putting some fuel in, and do some fuel system testing.  And to clean any 'swarf' out of the tanks!

Firewall Forward Fuel System

The last two lines for fuel are from the gascolator to the engine, and from the engine back to the firewall for return to the header.

I started working on this months ago as I wanted to extend the return line that came with the engine and could not get it off.  Rather than fight it, I am leaving it as is.

I really wanted the return line secured and decided to use the starter as a mount.  I had a -36 adel clamp which was too big.  It also wouldnt fit with the rubber on, so I modified it a bit.

These are all done (many months later). All lines were tested and fire sleeved.

Firewall penetrations, Final Firewall, Engine back in the crate

Need to go backward to move forward.  

Because I used a plexiglass firewall for mock up, it needs to come out.  Which means the engine, engine mount, firewall frame, coils, regulator, pumps filters, batteries, ground block, relays, shunt, etc, etc all has to come off.  The good news, this is the last time (fingers crossed - hopefully I didnt just jinx myself).

Couple things to do before it all comes apart.

• Determine final location of fuel return line through firewall, and make hose back to top of header.
• Cabin heat pass through
• Alternate air pass through
• Throttle pass through

Ready for removal

Few things to do, then the firewall gets completely disassembled.

One of the challenges is how to cut the big 2" holes (one for the umbilical, and one for the cabin heat duct).  Cutting holes is easy, as long as its not stainless.  My hole saws are of a fine 'Princess Auto' variety (think Harbor Freight).

Looking at the Glasair forum, there are so many opinions on how to cut them.  The TWTT instructions say use a hole saw over 1", and a unibit under 1".  My el cheapo hole saws made a lot of smoke and just dinted the material.

After consulting the forum, I decided to try a carbide tip hole saw and a punch.

Pretty much immediately, the punch started to warp the stainless - and it never fully went all the way through.  So those are going back to the store...

As a side note, I bought a new unibit... Millwaukee 'no jam' unibit.  Cuts stainless like butter.

Piece of cake.  Cut the 2" hole in about 4 seconds.

From there I used a drum sander to clean it up a bit.  The carbide hole saw is the solution...

Firewall disassembly begins...

Completely naked... I had to pull all the wires / hoses, etc back through the firewall.  This will be an awesome opportunity to clean up the wires, etc I could not reach.

Firewall in place (thanks John!).  I just hope it will fit once the blanket is adhered to it.  Fingers crossed.

Firewall blank with the plexi kinda laying in front of it.  I need to finish disassembling everything on the plexi.

Next is drilling.  As a test I tried the carbide bit with a hand drill today on a test piece.  Oh no, bad idea.  On the flip side, I did some 1" holes with the Millwaukee unibit in the drill press.  Super nice.  I think I have it all worked out now (fingers crossed).

The small holes - less than 1" were pretty simple.  the 2 big 2" holes were a bit more challenging.  The engine umbilical (which is up high on the firewall) was pretty easy, as I could do it in the drill press.  The 2" cabin heat hole was more challenging, as it would not fit in the drill press.  So I ended up essentially scoring it with the 2" hole saw with a hand drill, and then drilling a series of 1/8" holes around the perimiter, joining them with the dremmel and a cut off wheel, then smoothing them out with a carbide bit in a die grinder, then finishing with a drum sander.

Next problem(s)...

• I had planned on using the cable safe and cable safe II fittings for cabin heat, alternate air, and throttle.  Well, they are aluminum and won't pass inspection.  Need another solution.  However, after talking to my inspector the cable safe fittings are acceptable.... so..???

The above is the firewall closeout for the UL umbilical (described in previous post).  I ended up making an aluminum ring for the back that will be riveted to the firewall.  The stainless C shaped disks will be screwed through the firewall to the aluminum disk (with captive fasteners).  Hopefully this all works out.

Firewall flanges riveted.

The rivets supplied with the kit are Monel (aka stainless), and are SUPER HARD.  Definitely a 2 man bucking requirement.  Of the 54 rivets for the firewall, we had 2 bad ones that needed to be drilled / replaced, and 1 smiley.

Finishing up all the firewall aft brackets for the relays, cabin heat box, and engine umbilical pass through.  Then I can finish them (IE clean, alodyne, paint, rivet fasteners).  Then its onto the firewall blanket.

Test fit of the frame.  There was a couple holes I forgot to drill in the stainless and needed the pattern.

Then I had a nightmare... I could not remember if I had fit the air deflector with the frame and gascolator on.

Thankfully it fits.

Insulation blanket cut in half and taped both sides.  The TWTT instructions do not say much other than 'cut in half, tape the two halves together'.  The manufactured edge of the material does not have insulation (see below pic).

The solution is to overlap the manufactured edge and butt the insulation up against each other, and then tape both sides.

Insulation initially cut to fit.  Supposed to trim to 2", but I did slightly more, so need to correct.

I did the bulk of my wiring with the temporary firewall in place and the engine hung.  Now that all of that is out, now is the right time to clean up the mess and finish the last few connections.  I am actually rewiring all of the power connections through the firewall.  All of the new wires are extra long so I can route them nicely and terminate appropriately.  Its only about 10 wires... a few of them I had not done yet, but those are in progress.

Insulation adhered to the firewall, and orcotek tape in place.  I am about 4' short (ordered 10' from Glasair for $40).  The kit came with 16', but if doing 2 lines of tape from top to bottom on both sides when joining that is just not enough.  If you only do one side (which the TWTT instruction indicate), 16' would be enough.  I probably messed up about 1' of it where it folded over on me and I could not recover it.  The best method is DEFINITELY to do it in short strips and not try to wrap the entire ~12' of firewall in one piece (this tip came from the forum).

Top side...

Bottom side

There are a few puckers here and there, but once it is pressured up against the cage I am hoping they will come out.  Not that much will be visible when all is said and done done.

I've made back plates for the captive fasteners for the relays, engine umbilical, and cabin heat box.  These have all been alodyned and primed / painted.  Next is to rivet the fasteners in place, then rivet them in.  Also have large washers for the throttle pass through, UL pressure lines, main fuel line / return line.

Time to put all the fasteners in.... luckily they can all be squeezed and no bucking required.

Only 1 plate to go, then its onto ground blocks, pass through fittings, etc.

Good day today.  Everything is mounted except the -6 fuel return line and -8 fuel delivery line (ordered the wrong stupid fittings).

Everything has loctite applied to the fasteners that will be inaccessible after installation.

Rear view

There is a bit of slack in the insulation (which is a good thing).  Once it is pressed up against the cage, the slack should be taken up nicely (fingers crossed).  There are 8 cage attach points, plus 5 for the engine mount, etc.  Plus, you wont really see much of this anyway.

I think that is enough for one post...