Long crank before start

[allen00e350]

Let vehicle sit for 8 hours in a level position, vehicle will start with no problems, but if vehicle sits with nose up for less than 1 hour - vehicle will not start. Have to spray ether in the engine to help engine to start, while spraying ether noticed oil pressure gauge does not move until about 30 seconds after cranking with ether that pressure begins to come up and then will stay running a little rough at first but then smooths out.
Can any one tell me why I am losing oil from my upper high pressure reservior on '00 E350 7.3L.