MESSERSCHMITT Bf 109, VENTILATED OIL FILLER CAP

The Messerschmitt BF-109’s liquid-cooled, inverted-V12 Daimler-Benz DB 601 engine featured direct fuel injection.

Direct injection significantly improved low RPM performance, delivering superior aerobatic performance in manoeuvres where early versions of carbureted engines like the British Rolls-Royce Merlin powering the the early Mk I and II Spitfires, would lose power when the carburettor float bowl ran dry.

Advanced variants of the DB 601 also powered the Bf 110 and the Heinkel He 100D - going onto become one of the most mass-produced and successful high-performance aircraft engines of WWII.

The Bf 109’s Oil Filler Cap was located under a small, flush-fitting access hatch on the port side of the aircraft's engine surround just forward of the main engine cowling.

Earlier Bf 109s had the hatch located low on the surround with later variants, repowered with the larger and more powerful DB 601AAs, moving the filler hatch further up the surround.  

Manufactured by the German Deutche Benzin-Uhrin (DBU Works), the central cap cast markings read ’SCHMER’ or 'LUBRICANT' with the wording 'Beluftungsventil' or Ventilation Valve' in raised text around the cap at the base.

Made from an Electron magnesium, the DBU produced Oil and Fuel Caps for most Luftwaffe aircraft as well as their Auxiliary Drop Tanks.

Unlike Auxiliary Drop Tanks which were pre-pressurised to power the fuel up into the aircraft and were left unvented, primary aircraft oil and fuel tanks on both the Bf109 and the Focke-Wulf Fw190 required  ventilated caps, so five small holes were drilled into the middle of the universal DBU Works casting and a small spring loaded padded washer pressed into the recessed housing beneath.

The ’S’ shaped arms of this DBU Works Oil Filler cap slide under two large wing nuts on their 8mm studs which were then screwed down tight to secure the cap.

Mounted on its 100 yr old Mango Wood stand with a highly detailed hand crafted and airbrushed model of the iconic German fighter the Messerschmitt Bf109 and informative Fact Sheet, this would make an extraordinary and highly valued, original memento of Luftwaffe air power for any aviation enthusiast.

* Note that this Bf 109G Collectable is pictured with a 1/48 scale model rather than the standard detailed, but smaller 1/72 scale. Click on the 'Model Upgrade' option at the top of this page for the larger 1/48 scale

This Bf109 collectable comes complete with detailed 1/72 or larger 1/48 Scale Model, Mango Wood Stand & Plaque plus Printed Fact Sheet featuring photo of collectable on aircraft.

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