You're half right, half wrong, I found this with google,
http://www.google.fi/search?hl=fi&so...meta=&aq=f&oq=
here it says:
http://books.google.fi/books?id=SOIY...bypass&f=false
"Externally cooled units were equipped with a cooler bypass valve, that opens when cooler pressure reaches 27psi. This fluid is bypassed directly to the lubrication circuit. In the air cooled units, the bypass valve was eliminated, directing the oil directly to the lubrication circuit"
Now the question is, what kind of cooler bypass valve my oil pump has. Original, removed or blocked.