Gas and Oil

RFC Pilot · 14 April 2006, 08:57 AM

Does anyone know what the marking on the gas and oil caps on the German aircraft would of been?

What symbols or words would of been used? Photos would be great.

Thanks!

Pat Daily · 15 April 2006, 11:32 AM

On the Pfalz DIII and DIIIa there is a circular panel cover on the lower left side of the fuselage with a stencil above it that says Hauptbenzenetank. I assume that is the oil tank for a conventional 4 stroke internal combustion aircraft engine. I always thought the rotary engines used oil in the petrol or gasoline, but I am not sure if they had a separate tank or not.

Pat

Dan_San_Abbott · 15 April 2006, 09:45 PM

Pat Daily:
Hauptbenzenetank means main fuel tank. Benzene was the fuel that the Germans used, some form of gasoline. Oel is oil in German. Inline and Vtype engines used regular petroleum for lubrication. Rotary engines used castor oil, made from the castor bean. It is not soluble in gasoline (petrol or benzene.), consequently it does not loose its lubricity.
Blue skies,
Dan-San

Pat Daily · 16 April 2006, 05:06 AM

Dan-San

Thanks--I should have remembered oel--my 356B coupe has a decal that says oel on the oil filler. Duh?

Did they mix the caster oil in the gas or was it held in a separte tank?

Pat

jellytwig · 16 April 2006, 11:10 AM

Hi Pat, I believe that the castor oil used in rotary engines was supplied from a separate tank, unlike two-stroke engines where it is mixed in the fuel. Castor oil doesn't mix well with fuel. Rotary engines used a total loss system, that is, the lubricant was constantly fed to the engine and was blasted out in the exhaust and chucked out peripherally by the whirling engine, hence the liberal staining on airframes with only a few hours of airtime. According to an elderly relative, Harry Foreman, whom I had the privilege to meet some forty years ago as a child, the fumes from rotary engines also had an unfortunate laxative effect on aircrew, which they attempted to remedy through liberal doses of plum brandy! I know little of Harry's RFC and RAF service except that he was on BE's and finally on Harry Tates. He came home with a half-spent bullet lodged between his skull and flying helmet and kept it on his watch chain.
Best regards, Tony.

baldeagle · 16 April 2006, 11:31 AM

Use the "Search" function above and search "Castor Oil" and you'll come up with a number of threads about these questions, like:

rotary enigine questions