Without engine I could lift and sideways hoist the airplane. With the weight of the engine, I could no longer lift it with my hands. Placing a dolly under the wheels, I can move the airplane sideways.

Even with the gear through the doors, we still need the dollies to maneuver the plane. Although the tail can easily move, with the tail still inside the workshop the steering is limited.

We are going to locate the RV next to the workshop and tie the tail to a big beam.

Now we can carefully remove the dollies from the wheels and place chocks before the wheels.

The tailwheel is tied and I placed a sandbag on the tail, to prevent the tail going up. Since the wings are not attached I connected a jerrycan to the fuel lines (also the return line).

To get everything on video, I use different camera’s and angles.

With the engine running I check all the gauges on my EFIS, EMS and also on a separate laptop that I connected to the ECU. The sound of the 6-cylinder ULPower is gorgeous.

I found the whole engine start a big success, but we had to stop, because the weather got worse. We lifted the RV back on the dollies and dragged the airplane back to the workshop.

I’m really excited that both my parents were here when we started the engine.

Time: 4 Hours, Rivets:  0/0  (2021-05-23)

Time: 5 Hours, Rivets: 14/2  (2021-05-24)

Time: 4 Hours, Rivets:  0/0  (2021-05-26)

Time: 7 Hours, Rivets:  0/0  (2021-05-30)

Video

Of course I was happy to open up my cowl for ULPower to checkout my setup. I was filled with pride when Patrick and Jakob gave me compliments on my engine installation. Since they are the experts on this topic.

They check out the various possible locations for a Turbo and Intercooler and they made several photo’s, took measurements and created sketches.

They also gave me extra tips on how to improve installation and we discussed several options. For me this visit was already a big success.

Patrick also discussed the Air intake for the engine. I wasn’t sure what the best (achievable) setup would be, but together with Patrick and Jakob we figured out the best solution.

It’s really great when you can have an in-depth conversation between you as a builder, with one of the designers of the engine that you use. I realize this is very rare and treasure this opportunity.

Together with Patrick and Jakob, we did a check of my avionics and alarm lights, which checked out ok. However the CAN-BUS communications from both the MGL RDAC ULP and MGL RDAC XF to my MGL XTreme EFIS and EMS did not work correctly. When connecting the laptop and running the analysis software, the ECU was OK.

Again, I’m delighted that ULPower visited my workshop and I hope they can make a big success with the Turbo version of the UL520. If I had to select an engine at this point in time I would consider that engine, although it is considerable more expensive and heavier.

Earlier this year, when I picked up my custom cowl at ULPower, they were testing the UL520T and I must say it looked (and sounded) magnificent.

Working on the CAN-BUS, it turns out that the drawings of the connector is wrong.

I didn’t purchase a pre-built wiring harness, because those are expensive and the components are cheap. However if the plans are incorrect, it takes some time to fix it.

Here is a view of the (stock) MGL RDAC ULP. For some reason MGL does not include the RS-232 chip (which costs less then €2,-), so I had to solder this myself, including 4 minuscule capacitors. All SMD devices, so that’s just great when you’re over 50 and your eyes can hardly detect those components let alone solder them nicely.

After fixing the CAN-BUS, I continue with the Fuel system. Unfortunately I have to crawl into the forward part of the ‘cramped’ cockpit to work on it.

The most challenging part of the fuel system is the most forward tube from the Fine Fule Filter to the Bulkhead through the Firewall. I have all the ‘parts’ of the fuel system in the cockpit on the floor. I hindsight I might have improved maintenance by moving the Fine Filter to the engine side of the Firewall. This is however the most compact setup, which I’ll probably regret at the first maintenance job after 15 hours of flying.

I didn’t use the ‘standard’ ULPower Fuel system. I did use the Filters and Pumps that come with the kit, but I decided to use different connectors, to make the whole construction fit the center part of the leg space.

Time: 6 Hours, Rivets:  0/0  (2021-05-02)

Time: 5 Hours, Rivets:  0/0  (2021-05-03)

Time: 6 Hours, Rivets: 10/0  (2021-05-04)

Time: 2 Hours, Rivets:  0/0  (2021-05-06)

Time: 5 Hours, Rivets:  0/0  (2021-05-09)

Time: 7 Hours, Rivets:  0/0  (2021-05-12)

Time: 6 Hours, Rivets:  0/0  (2021-05-16)

Video

There is an extra Cowl part delivered for the Air intake of the Oil Cooler. However it took some time before I figured out how to cut the Air Intake and the Bottom Cowl to make it fit. And of course I made a noob mistake working with carbon.

The ULPower engine is delivered with the Oil filter screwed into the engine. The installation kit also holds an Oil thermostat, that opens the flow to the Oil Cooler (if necessary). So first task is to remove the Oil Filter and install the thermostat.

The thermostat has two hose connectors, just as the Oil Cooler and the goal is to connect those with the hoses included. Since setups may vary, you have cut the hose and clamp the connectors to the hose yourself.

The Oil hoses have a steel braided sleeve and I tried the hand saw, but my results were not suitable for getting the connectors installed after sawing. Here I use the Dremel and I have the hose taped with Duct-tape on both sides to prevent the sleeve from ‘unwinding’.

The connector consists of two parts, the outside nut and the inside connector. You have to push the hose in the Nut and then screw in the connector. After several tries I found that the best way is to:

• tape the hose end before cutting
• gently insert the hose end in the nut (with all the steel threads in the nut)
• push the nut with the hose against the workbench
• remove the tape
• twist the nut with a wrench to make the hose slide into the nut

For inserting the connector in the nut, apply some oil or grease, this makes it way easier to screw the connector in the nut.

According to the installation guide of ULPower, the hoses should be routed ‘around’ the propeller flange. I don’t see why I can’t directly connect them, but it’s probably a space issue. We have to be careful though, the hoses are routed very near to the arm with the electronic connections of the propeller.

I’m checking the (interactive) installation manual of ULPower, which is exceptionally well structured. I’m wandering what is worse, greasy fingers on a paper manual or an a tablet.

Making the last connection to the Oil Cooler and adding some protective rubber to prevent ‘chafing’ the hose.

Here’s the result. You can see the thermostat between the engine and the oil filter.

Next is the Air Intake for the Oil Cooler. As you can see the mold it came of, allows for many variations. At this point in time I’m still clueless on how to cut these parts.
At least it should not stick ‘over’ the nose of the Cowl. Also the forward top side fits pretty good on the bottom cowl.
A lot of trimming to do, so many opportunities to screw things up.

Here is the first ‘rough’ cut in the Bottom Cowl, which looks horrible and considering the costs of the Cowl made me shiver.

But I finally figured out that I need to cut a wedge type of hole into the Cowl to slide the Air Intake in. Note the wooden beam in the back, clamped to the cowl to keep the shape steady.

Now we have to center the parts and drill holes for cleco’s.

The fit is getting better and better and now I can use sand paper for the last edges. However this is also the point where I make a mistake. I did all the fitting while the Cowl rests on the workbench. Turns out it slightly deforms due to gravity. After gluing the parts together with resin, it didn’t fit the fuselage anymore. So I had to cut again and do it all over.

While the resin and carbon are drying, I work on the Air Boxes that guide the cooling air around the engine. Making these two fit the Cowl is a whole other story.

Time: 7 Hours, Rivets:  0/0  (2021-03-31)

Time: 8 Hours, Rivets:  0/0  (2021-04-04)

Time: 4 Hours, Rivets:  0/0  (2021-04-07)

Time: 6 Hours, Rivets:  0/0  (2021-04-14)

Time: 5 Hours, Rivets: 25/0  (2021-04-17)

Time: 5 Hours, Rivets:  0/0  (2021-04-18)

Time: 6 Hours, Rivets:  0/0  (2021-04-20)

Video

Before installing the engine, I checked all the bolts of the engine mount on the correct torque.

To prepare, I dragged the engine under the ladder and removed the engine guard beams. The ULPower engine is transported in a crate with all the installation parts in there.
The wire harness on top of the engine is the connector between the engine and the ECU.

The ULPower 520 iSA engine looks great. It has a yellow lifting hook. You should NOT lift the engine only with this hook. The hoist method is to attach a strap between the hook and the crankshaft.

Ready to lift the 6 cylinder engine out of the crate. I installed the two straps between the lifting hook and the crankshaft. The second one is just a backup in the very unlikely case the first would snap.

I’m eye-balling the distance between the engine mount and the ladder. Also I connected both bottom ladder rungs with a strap to prevent the ladder from collapsing.

Lifting time. While my dad is controlling the trolley, I guide the engine between the legs of the ladder. We lifted the tail wheel of the airplane, so the engine mount is level with the engine itself.

I made a big error here, with the engine mount extension. The grey powder coated steel part extents the (white powder coated) engine mount, in order to shift the engine 8″ to the front. This is necessary, because the ULPower engine is much lighter than the Lycoming engine, that is used in the design of the RV-7.

To get the CG in the right range, I had to extent the engine mount. However, I’ve accidentally attached the extension unit upside down. This shows by the angle of the extension going up. This resulted in the engine being located too high. So high that the cowl would never fit. Because we were focused on installing the engine (and most notably the rubber attach points), we completely missed this error.

Fortunately my wife saw the issue immediately when she entered the workshop to see the progress. When she said that we installed it wrongly, I thought, what does she know. Well shame is on me.

Done, the engine is attached to the (upside-down) engine mount (sigh). Now we can remove the ladder and all the transport and lift accessories.

Still laughing, because We didn’t figure out we screwed up. Now we can continue the installation.

First we have to replace the exhaust rings that were used by the test rig in the factory. The factory provides new (copper) rings that we need to install.

Some bolts are really hard to reach. With some little grease (AeroShell 22) we insert the new rings and they stick. Now we can insert the exhaust pipe.

The cramped space and the angle of the exhaust, makes it really hard to torque the bolts to the right value.

While my dad keeps working on the exhaust, I start installing the throttle cable. As per the manual, you do need to make the throttle cable curve, while installing it. The reason is that a straight cable could be actuated by vibrations (movements) in the engine.

Time to connect the huge starter engine cables. As you can see I still didn’t figure out the wrong installation.
And this is the point where my wife told me the engine is too high. After my short period of denial, going through possible screw-ups, I realized that the extension did NOT have a ‘this side up’ sticker.

We are deciding how to fix this. Later that day I decided to hang the engine back in the ladder and unscrew the nuts of the extension on both sides. Turns out it is much easier to attach the engine with the extension loose from the engine mount.

Only one hour later I had the extension turned around. So now it fits.
A little strange is the position of the exhaust spring clamp rings. They look wrong, but I have to modify the exhaust anyway.

It’s after dark, but I was really determined to fix the extension that day.

Time: 7 Hours, Rivets:  0/0  (2021-02-14)

Time: 7 Hours, Rivets: 74/0  (2021-02-17)

Time: 3 Hours, Rivets:  0/0  (2021-02-18)

Time: 7 Hours, Rivets:  0/0  (2021-02-21)

Video

I used Kicad to make the schematics. The Avionics schematic was rather easy, as it’s just browsing through the manuals of the various Avionics and merge the schematics.

The Console is almost completely designed by myself. The Lights are integrated with the Flyleds board. Although the space between the seats of the RV-7 is small, I really wanted a console with a Throttle quadrant, seat heaters, Lights and Flaps.

The last schematic is the one for the Engine, which is loosely based on Figure Z-19 of the AeroElectric Connection from Bob Nuckolls and the manual of ULPower.

Some of the standard electronics do not have a proper brackets to attach the to the panels. To solve this I use my 3D printer to crate brackets. This one is for the (internal) USB power supplies.

The Panel only has the bare minimum of Avionics and Switches. The two big spaces in the middle are preserved for two ‘standard’ tablets.

Now I can start wiring up all the components. I created several power bars (and a ground bar) to distribute the power of the battery via the fuses to all the Avionics.

The ECU of ULPower comes with two wiring harnesses, one from the Engine to the ECU and one from the ECU to the Avionics. The wires are all color-coded and bundled with colored heat shrink sleeves.

It took me almost 60 hours to complete all the Avionics and Wiring.

Time: 4 Hours, Rivets:  6/2  (2020-12-21)

Time: 7 Hours, Rivets: 10/0  (2020-12-22)

Time: 6 Hours, Rivets:  8/0  (2020-12-24)

Time: 4 Hours, Rivets:  0/0  (2020-12-26)

Time: 8 Hours, Rivets:  0/0  (2020-12-29)

Time: 8 Hours, Rivets:  0/0  (2021-01-01)

Time: 8 Hours, Rivets: 16/0  (2021-01-06)

Time: 5 Hours, Rivets:  0/0  (2021-01-08)

Time: 5 Hours, Rivets:  0/0  (2021-01-09)

We were invited (as potential buyers) for one of their ‘familiarization classes’ at the factory. The reception was very friendly and Evelyne and Patrick made us feel very welcome. After an hour of history and overview on the engines, Patrick showed all attendees around in the factory itself. Stunningly this factory is operated by a single engineer and a completely automated CNC-robot.

At the entrance there where palits with blocks of Aluminum. The robot runs 24/7 and picks Aluminum blocks, places them in the CNC-machine and returns the finished pieces. On the right you can see finished parts, on the left there are different tools for the CNC-machine that are placed in the machine by the robot if it requires to execute a different process.

On regular intervals the engineer requests the robot to pick finished parts and deliver then to him for inspection and measurements. All parts are logged including their measurements and deviations.

The core of the engine is created out of two blocks of Aluminum. You can see a six cylinder in the front and a four cylinder on the back of the palit.

The robot works day and night and the engineer makes sure that before he heads home, all the slots are filled with Aluminum blocks, so the machine can work all night. Obviously the robot is surrounded by storage racks, so no one can reach the robot (or actually the other way around, because I think it won’t even sense it when it decapitates you.

The finished cylinder walls with the cool-fins are stored in a rack with engine serial numbers on them. Besides the CNC production of parts in Ieper, ULPower also has a aircraft engine assembly factory in Oostende (Belgium). This assembly facility takes the parts created in Ieper and build the actual ULPower engines.

The rest of the factory is empty, except for some manual tools and auxiliary parts. However I guess the manual tools are obsolete, because they didn’t run at all.

Meet the ULPower 520iSA. It’s a six-cylinder, 108kg, 200hp Lycoming alternative.It has both air and oil cooling and a ECU controlled injection system.

It is the engine I choose for my RV-7 and it looks great.

Time: 5 Hours, Rivets:  0/0 (2020-02-21)

Video