hello 1975 300d will start now will only idle for a min or so if you run it faster than idle it will keep running ,but if you return to idle it will soon die and you will need to pump on primer bulb again when its going to die there is NO bubbles in the clear filter but no real flow to be seen the fuel tank screen was cleaned and all filters changed it seams to run longer if you pump the primer when the engine is running it will keep running at about 1000 or so again no bubbles does this thing have a fuel pump and if its week would it pump enough at a faster engine speed to keep it running also it shows no oil pressure the oil has been changed the valves dont clatter it has a manuel guage we took it loose from the oil filter base and blew a little air in the guage moves fine is there a bypass in the oil pump i need to clean also you can remove the oil filler cap and see lots of freash oil on top Thanks for the help