Motor oil in vacuum wiper lines and pump

[ZGjethro]

I just removed the mechanical fuel pump from my 52 truck. It has not been pumping gas for years since I have an electrical unit, but I developed an oil leak in the area and traced it to the old pump. I have not taken the pump apart yet, but I did take the cover off of the vacuum pump side, and it was full to the top with motor oil. I am not concerned about the pump since I am blocking off the pump opening, but I am curious if this is a common thing with these pumps. I have heard of the fuel pump diaphrams letting gas into the crankcase, but not oil into the vacuum wipers. Anyone have a take on this?

[Tuko]

my seal was shot between the cam lever area and the vac pump allowing engine oil down into the vacuum chamber. the rebuild kit gives you all new seals if ya rebuild it for the 70 bucks they sell the kit for you can probably make a little profit!