Like almost all twelve cylinders, this engine also has a bank-angle of 60°. However, unlike the motor vehicle engine it is upside down, i.e., with the crankshaft on top then down to the propeller with a ratio of just under 2 : 1. Thus the propeller is mounted roughly in the center in front of the engine.
If you turn the engine over, the cylinder-numbering can be seen, almost the same as is common in the motor vehicle field. Only the first and seventh cylinder are facing the propeller. Seen from there, the numbering begins on the left. Of course, the twelve-piston-serial pump to the petrol injection is also mounted as a suspended unit.
Performance specifications must be looked at in a different way because the boost pressure depends on the altitude. The nominal power is given at a height of 5700 m above sea-level. The performance adaption is achieved by a turbine which is driven by the engine, through a hydraulically adjustable clutch. The clutch, on the other hand, is controlled by a barometer membrane box. .
An engine as big as this one probably does not allow itself to be fairly evenly air-cooled. Therefore, there is a coolant made up of 50 liters of water, 50 liters of glycol and 5 liters of protective oil. The instructions when repairing are interesting: the coolant should be removed, then the engine is to be rinsed out with warm water and once any sludge has settled, the coolant can again be re-used. .
The 0,2 variation in compression between the two cylinder banks can probably be led back to the varying cooling from the outside. All together, the charging pressure varies between 1,05 and 1,4 bar, this is how the difference in performance comes about. Each cylinder by the way, has two intake- and two exhaust valves. .
The crankshaft is quite common with 7 journal bearings and 6 cranks, which each carry two con rods. This is why the two cylinder banks are slightly offset to each other, around which the two halves of the aluminium crankcase are bolted. The pistons run in wet-sleeves. Apart from the four valves, the injectors are also accomodated in the cylinder head. .
The path that the fuel takes in an aircraft, where all possible directional conditions must be considered, is very interesting. Inside the fuel-tank there is an immersion pump, to which the mechanical feed-pump is joined. Before the fuel enters into the injection pump it runs through a bleeder. .
In a direct injecting engine, not only must the ignition take place at a precisely defined point. Thus the fuel is injected at 65° after TDC into the intake stroke. Then apparently, a good swirling in the compression stroke is guaranteed. At least the path of the regulating rod is electrically determined, so that, together with the tachometer sensor, the momentary consumption can be indicated to the pilot. 11/12