Product Idea

Working Four-Cylinder Engine

Working four-cylinder engine

Specifications :
-Configuration : Inline
-Number of cylinders : 4
-Valves per cylinder : 4
-Valvetrain layout : DOHC (Double OverHead Camshaft)
-Bore : 12 studs
-Stroke : 12 studs
-Displacement : 5429 cubic studs
-Type of internal combustion engine : Four-stroke
-Firing order : 1-3-4-2

Having always been fascinated with cars, engines and other various mechanical contraptions, I tried my hand at designing a set that would offer the most accurate engine building experience Lego bricks could achieve at a 1:1 scale.

My main goal was to demonstrate how an engine is assembled and them how it works once the assembly is completed which is why this set has great educational potential.

In order to achieve this, I designed the model as a bare see-through skeleton housing the rotating assembly and other various parts so that every interaction could be visible and easily understood.

The assembly is done in the same way a real engine would and you follow similar steps to build it while learning about every aspect of the whole mechanism, the most interesting of which is valvetrain timing.

The relationship between the various engine components is perfectly replicated, the rotating assembly and valvetrain both work in unison with the same timing a real engine would have.

A color code was used to not only bring back the classic small-scale Lego engine look with the yellow pistons and light bluish gray engine block and rods, but also tell apart fixed parts from moving ones in order to help understand how an engine works.

The engine can either be manually operated by using the crank handle or automatically operated with the battery and motor provided in the set, both options connect to the back of the crankshaft.

A display plaque is fixed up front on the stand and is intended to show an image of the engine and to communicate its typical specifications as well as interesting information about it.

Due to software constraints, I was unable to model the timing chain connecting the crankshaft to both the camshafts correctly, but it will be included despite not being pictured.

The set includes all the following parts :
-1 X Engine block
-1 X Crankshaft
-5 X Main bearing cap (2 of which are slightly different to attach the display stands)
-4 X Piston
-4 X Wrist pin
-4 X Rod
-4 X Rod cap
-1 X Cylinder head
-2 X Camshaft
-12 X Camshaft cap
-16 X Valve spring
-8 X Intake valve
-8 X Exhaust valve
-1 X Main timing chain
-1 X Secondary timing chain
-1 X Timing gears
-18 X Rubber band
-2 X Display stand
-1 X Display plaque
-1 X Crank handle
-1 X Electric motor assembly
-1 X Battery assembly

See pictures for engine disassembly and parts list