foil load

Hello.
The text is about the diesel engine. And one sentence is not clear to me:
When started the diesel engine carries its foil load in a few minutes.
Would you please explain what foil load is and what the meaning of the sentence is.
Thanks a lot.

Where did you see this? Can you give us a little more of the original context, please, and the source?

To me, it seems that this should read "full load." What, exactly, is your source? If it's online, can you provide a link? Could this be an error?

In searching for diesel engine "full load", I found several instances where "foil load" occurred in the description, but when I opened the PDFs, I found full load in the document (example). I know nothing about diesel engines, but it would appear to be a misprint.

I found the same document at about the same time. The paragraph with the quoted sentence begins "The diesel engine is one of ,me most efficient heat-engines..." Clearly, ",me" should be "the." There are several other errors in the document as well. The sentence "If used for any vehicle the engine has to have the reduced weight per horse power of the engine" is nonsense. This is unfortunate in a document that is intended to be used for learning English, but sadly it's common.

To answer the original question: I am certain that "foil" should be "full." That is also consistent with my understanding of diesel engines.

Almost seems as if it was a hand written document scanned using OCR then converted into a PDF.