The success story of the first vehicle fitted with a direct-injection diesel engine
March 12th, 1924 – it´s a cold spring morning at the MAN plant in Augsburg and the ground is still muddy from the night´s rain. In the yard stands an old M.A.N.-Saurer tracked vehicle - its unique feature being that the truck is driven by one of the first three diesel engines to be tested by MAN in a commercial vehicle.
Although Rudolf Diesel applied for his first diesel engine patent in 1897, the engines were mostly stationary and used to power ships. This was due to one simple reason - to begin with, they were extremely large and heavy. Between 1919 and 1923, the diesel engine was then developed further at the Augsburg plant, being adapted for use in commercial vehicles and in 1924, the first three new experimental engines were constructed to drive commercial vehicles. The solution lay in dispensing with a heavy compressor and installing a fuel pump and injector nozzle instead.
The engine hood is still standing open. A works engineer has probably just done a final inspection of the new No. 2 diesel engine, for this truck with the new "heart" is about to begin its transfer journey to Nuremberg.
For the 140 kilometers between Augsburg and Nuremberg, the two engineers, Mr. Sturm and Mr. Wiebicke, will need five hours and thirty minutes. To be on the safe side, they take the original gasoline carburetor with them on the truck bed as a reserve engine – but it won´t be needed because the new diesel engine will run perfectly throughout the entire journey.
Upon arrival, the new direct-injection diesel engine for vehicles is removed from the old tracked truck and built into a more modern 3-ton Kardanwagen. The time for intensive test drives has begun. After six months and a test circuit of 2,500 kilometers, it is clear that engine No. 2 runs and runs. Next stop – its presentation at the German Motor Show in Berlin from December 10th – 18th, 1924.
MAN engineer Sturm insists on driving the car to the exhibition grounds in Berlin himself, needing two days to travel from Nuremberg in that era. And, apart from a few dirty valves, there were again no mishaps on the way. "Journey successfully completed", wrote Mr. Sturm in a telegram to his MAN colleagues shortly after reaching the River Spree.
In all, two diesel engines for vehicles are presented at the show by MAN´s engineers. While one of them can only be viewed with wonder in the form of a mounted exhibit on Stand No. 447 in Exhibition Hall II on the Kaiserdamm, "No. 2" can actually be tested by the world. For nine days, engineer Sturm and transport foreman Andreas Wittmann drive curious exhibition-goers and customers around the streets of Berlin - a service that excites both the public and the trade press. The verdict issued by 'VDI Nachrichten' reads, "In the sector of machinery for trucks and the related fuel issue, the compressorless diesel engine from MAN was probably the most important innovation to be offered throughout the entire show.“
Its success in Berlin is the starting signal for production of the new diesel engine series D 1580 A respectively B and subsequently for the series production of diesel engines for commercial vehicles at MAN – an important step. The first customers to each receive a vehicle diesel engine for test purposes are 'Kraftverkehr Bayern' (Bavarian Motor Transport) and the 'Reichspost' in Munich, Augsburg and Nuremberg. The first customer truck to be fitted with a diesel engine is a beer transporter belonging to a public limited company, the 'Zum Hasen' brewery, while the first omnibus engine was acquired by the 'Reichspost' in 1925. The beer transporter was in continuous use in Augsburg for several decades without any major breakdowns, but finally destroyed in an air raid during the Second World War in 1942.
From the outset, MAN developers saw two definite sales advantages, namely the reduced weight of the engine and the tremendous 80-percent savings in running costs compared with conventional carburetor engines. Arguments which were decisive for customers even then. By the mid-twenties, the demand from the truck department had already risen to such an extent that the manufacture of diesel engines for commercial vehicles, which was already underway, was moved to Nuremberg. And even ninety years later, this segment continues to be an important part of the overall production network. Today, the development of commercial vehicles at MAN is still focused on economic viability and efficiency – the two sales arguments of that time.