F -Head Oil Pump Design

[JW1954WAGON]

Hey Folks,

So pulled this oil pump out of F-head in my 1954 Wagon. Trying to figure out why the design is different with the double drive gear vs. everything else I have seen showing 1 gear behind the drive plate. Thanks for any advice!


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[LarrBeard]

I'll make a guess - subject to correction/clarification.

What you are seeing there are the rotors in a positive displacement, "external gear" pump - not actually drive gears.

https://www.michael-smith-engineers.co.uk/resources/useful-info/positive-displacement-pumps

[JW1954WAGON]

Ok thanks for that info! I was really more curious if this was an OEM oil pump used on the f-head. There is probably nothing wrong with it, just doesnt look like the replacement version.