[HawgRyder]

The oil tank to pump should be all downhill (gravity feed) unless you got inventive and change the feed line (I found one on one car that looked beautiful...but had an upward kink in it) and had an air lock.
I vote with Flat6pac .... the rubber Oring (gasket) is the most likely.
As Andrew suggested...perhaps priming it might solve the problem...if it doesn't and oil pours out of the oil drain as you are priming ... then the gasket IS the problem.
Bob