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LEGO TECHNIC Motorized Excavator 8043 Review



The Lego 8043 is a model released in 2010 – During its time of release, it became one of the most comprehensive, the most detailed and marvelous Lego models ever built, and has occupied a space in both the hearts – And shelves – Of longtime fans.


The box that comes with the 8043 is a pretty large one, to say the least – Probably the same size as the Lego 8421 and the Lego 8275. A flap is found on the top of the box, which, when opened up, will show you the range of functions that this build can do. Meanwhile, the backside of the box tells you more about the alternate model, as well as the instruction manual that came with the box. The alternate looks just as nice as the one found in the main model – Pretty much similar to a tracked loader. Much like the other Lego boxes released during this period, you might have to cut off the back corners to fully open it.


The 8043 contains nine types of poly bags, a bucket, three variants of instruction manuals for the main manual, the usual Lego sticker sheet, and a huge pile of Power Function components. Several of these bags do contain other tinier bags. Two of them are carbon copies of each other, while the rest contain the other parts needed for the build. According to past owners, the sticker sheet slides around in the box so it ended up becoming slightly mangled and crumpled when taken out. They could use some protection.

This build contains lots of parts – As mentioned earlier, this was one of Lego’s biggest builds during the time of its release. According to the official Lego website, the build has a total of 1123 parts.


For the 8043’s Power Functions elements, there are four M motors, 2 IR receivers, 2 IR transmitters, a battery box, and four versions of linear actuators. Compared to the Lego 8275 bulldozer build, the 8043 contains more than your usual amount of actuators in a Lego build, so there will be instances where you have to use them for other purposes. The two additional actuators can be used as gearboxes, as well as a support for their digging arm where it is connected to the superstructure. Also found here is a huge collection of panels, including ten long-angled panels 64393 and 64681 in yellow. These two parts are new and have not been seen with previously released sets.


You can find loads of studless beams with the builds along with the ones that have their own studs. The 13L beams that come with the build have a dark gray hue, and there’s a good reason for that – Most likely to help in setting them apart from the 15L beams. If that is indeed the case, then children can probably construct this build with the help of an adult. But of course older children, teenagers, and grown-ups can construct this build too. The box also contains four variants of transmission rings and four types of extensions – These are hard to find in major Lego builds nowadays. Other parts include ten new pins with cross holes in them, and eight pieces of 3L universal joints.


If we base the epicness of a set on the amount of gears it currently has, then it’s safe to say that the Lego 8043 is one of the best sets around. If we take a look at the gear collection, we’ll see that there’s a total of 71 gears which include fourteen hard-to-find ones and sixteen tooth clutch gears. This is twice the amount of gears found in other Lego builds. Also included in the build are four larger gears with an ample axle collection. These aren’t just your typical Lego axles – They are the unusual stop axles found in bigger builds. These 3L stop axles come in a darker tanned hue, compared to the other axles in 2010 builds that have a lighter shade. However, the real treasure here has got to be the 4L stop axle. This is a pretty big deal since in 2010, the 4L stop axle has only made its appearance in two sets, including this one.


As far as we know, there’s only one brand new part included inside the build. Then you have those six new brackets or gearboxes which all carry a same size and shape to the linear actuator bracelets, but are slightly stiffer. Much like the brackets found in most Lego Technic builds, these ones come in a matte black hue.

The initial part of the build is the tracked carrier. Everything in this build is completely structural without any moving parts. The next part of the build is the driving systems made for both the right and left side of the tracks. The forward sprockets are the only ones that are powered, and each of them have their own independent gear system, allowing the build to move around more. Some owners have managed to use the new parts as gearboxes for the 8043. The gears found in both the left side and the long axle are the input used for the structure. There are two brand new B-Level gearboxes which are meant to turn the torque overboard. Eight tooth pinion gears are also found right in front of the drive system.

After installing the unsprung sections in the build, the tracks can now go on. However, these parts aren’t even pendular so the complete assembly is rigid.


And now we have this technique that has been utilized in at least several sets before the 8043. If the motors initially used for driving these tracks are included in the build’s base, then these wires might have to pass through the turntable right up to the battery box. Some owners have complained that the wires would tangle up once the completed model slews. So to solve this issue, we suggest placing the motors inside the superstructure first. However, this also means that the drive system has to pass through the turntable first. To be able to pass through an axle through a rotating part first, it has to be in the axis of rotation. This is actually quite easy with the help of one axle. But how exactly do you place in two functions, as well as two axles, inside the similar axis of rotation right in the middle of the turntable? The answer is by using the coaxial drive system. The long black axle right in the middle of the build is responsible for driving one part of the tracks. Meanwhile, the other side is driven by the outside gears, which pass right through the turntables with the help of gray idler gears and its accompanying red transmission rings. The outside assembly lets the build spin around freely on the inside assembly, without having to switch the middle axle. So to sum it all up, the build now has two coaxial functions. There are also two tanned 20-tooth double gears that is responsible for driving up two sides of the build’s tracks.


Next part to assemble here is the gearboxes and motor assembly. We’re pretty confident here when we say that the 8043 contains most comprehensive gearbox assembly in any Technic build. First thing you have to do here is to install the four motors side to side, and attach them to the IR receivers. Next step is to slowly tuck away the wires, and make the entire build compact and all set to be placed inside the gearbox. Keep in mind that the three axles sticking out of the build aren’t connected to the motors.

The next step is to install the battery box and the rear cosmetic assembly. This keeps the build together and prevents it from collapsing.

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