DBU Kraft Stoff filler cap
 

Hello, long time reader. This Forum has provided me with hours of reading, and great help. I am an amateur collector of Luftwaffe history. Recently I transitioned from signatures on postal covers to aircraft artifacts. It is daunting at the beginning, but I am trying hard to expand my knowledge.
I read the hints to new members, and that is my introduction.
Now that I can post I hope to help others as well.


I recently purchased this item, and I am stumped. After hours of reading I can not re-find the information I am basing my thoughts on what this is. I remember seeing a diagram of a drop tank that had an access hatch, and the filler cap under it. So, I figured this would be a good beginning with you all.
-It only has one hole on the ears for the retention chain.
-No vents.
-A makers mark I do not recognize.*see edit


If you could please help me with a link to the information, and how you found it, that would be very helpful.
Thank you

Re: DBU Kraft Stoff filler cap
 

DBU....

Re: DBU Kraft Stoff filler cap
 

Thank you for the reply. I know about DBU as a company. I may have posed the question incorrectly. Is this off a drop tank? If it was off a planes primary fuel cells it would have to be vented?

I have continued searching, but still need some help.

Re: DBU Kraft Stoff filler cap
 

Here is a close up from one of the He219 cells at NASM Udvar-Hazy.

Tony

Re: DBU Kraft Stoff filler cap
 

Thank you for your help. The image you've referenced you can tell it is vented, the holes are drilled through the cap. My example is not drilled out, leading me to believe it is off a drop tank. I can not find a good picture or in the manuals,but I am still trying.

Re: DBU Kraft Stoff filler cap
 

Hello

Yes, your cap can come from a drop tank. Here an illustration :

http://www.detektorweb.cz/images/sto.../1397/obr3.jpg

and another one :

https://axis-militaria.com/wp-conten...23815576-7.JPG

Have a nice day !


J Schreiber

Re: DBU Kraft Stoff filler cap
 

Thank you very much, your bottom photo most definitely is DBU marked, and helps me greatly. What liter do you think that tank is?

The top photo is the "typical" drop tank filler cap, it looks slick no markings by maker.

At what point in the war did they change makers, and which example is earlier?

Re: DBU Kraft Stoff filler cap
 

This is a standard cap for a standard airplane tank, used in many airplanes during WW II

Re: DBU Kraft Stoff filler cap
 

Drawing below.

Matti

Re: DBU Kraft Stoff filler cap
 

Fuel cap (without vent) also used on Bf 109E.

ClinA-78

Re: DBU Kraft Stoff filler cap
 

Fuel cap from a bf-110 G-3 and Schmierstoffbehalter .
Is this cap for mixing oil and fuel ?
Very intressting thread and thanks for contributions.

Re: DBU Kraft Stoff filler cap
 

Thanks, that one does not look vented. It also appears to be not on a drop tank. Which book was that drawing in?

Re: DBU Kraft Stoff filler cap
 

That is a vented type oil cap, there are several type of schmierstoff caps,
I have one I will provide example.


Pg. 190 of this document has the drawing, for this example
https://www.deutscheluftwaffe.com/ar...sanleitung.pdf

Re: DBU Kraft Stoff filler cap
 

Could you please show me an example of a non vented DBU filler cap other than on a drop tank?

Re: DBU Kraft Stoff filler cap
 

The drawing is from the booklet "Kraftstoff-Armaturen" published by DBU (Deutsche Benzinuhrer-Gesellschaft m.b.H.) on 1 Okt. 1937.

Matti

Re: DBU Kraft Stoff filler cap
 

Thank you, I will look further into that this evening.

Re: DBU Kraft Stoff filler cap
 

Could you please tell me where to read more on this?

Re: DBU Kraft Stoff filler cap
 

I don't know where to search but I found the said cap on Bf 109 E-1 WNr. 3479.

ClinA-78

Re: DBU Kraft Stoff filler cap
 

Hi, The caps that I have, show a few interesting details. The DBU marked Kraftstoff caps come in vented and unvented type. The casting has the same part number 8-4520A cast into the reverse of the small attachment screw arm, despite the fact that the casting is different in detail, particularly the "air vented" cast lettering on the vented type. They are made from an Electron magnesium. It can be deduced that the vented caps were generally fitted on unpressurised fuel tanks, also generally gravity or low pressure refuelled. It is not known to me if there were specific aircraft with internal tanks that required unvented Kraftstoff caps. The common external 300 Litre droptank required air pressurisation to transfer the fuel up into the aircraft system and so, they had a sealed cap. You can see that in the photos of the droptanks in post#6. There is another point, the DBU caps have a large screw arm for a 12mm threaded stud and a small screw arm for an 8mm stud. This arrangement controlled the fitment of the cap to one orientation. You can see this on the second photo in #6 which I think shows the early standard of droptank cap with the sealed type 8-4520A DBU cap. However, later droptanks had a standardised sealed cap, that I think is shown in the first photo of #6. The standardised late cap has both arms with cutouts for 8mm studs. The late cap is made of alluminium alloy and has no words cast into it. In original condition they are painted a light green/blue. The standardised droptank cap has the following id cast into the metal of the arms: 3355.4 gyq N.9 (where 3355.4 is the alloy spec and gyq the manufacturer code) on one arm and, R-05615-39 (the part number) on the other arm. Cheers

SM

Re: DBU Kraft Stoff filler cap
 

Thank you, what an articulate post. I greatly appreciate the details. This forum has an exceptional amount of knowledge.
As other posters have pointed that possible, and known to them on an EMIL had a non vented fuel cap. You point to this, too. I would be curios then where the system is vented. That is probably for another discussion.
I think you have answered what my original search was for, and others have enjoyed it.

Re: DBU Kraft Stoff filler cap
 

Very interesting about the different size studs for orientation on the DBU caps.