the plot thickens!
ok, shannon you can now sleep easier, i have removed the primer bulbs
I installed all new fuel line, and hose clamped the joints around the fuel filter (i don't/can't use in tank filters with my setup). Installed a brand new mikuni fuel pump.
Start the engine up, idles fine, mid-range fine, max power - hey cool its running. I set it at full power, clamp the throttle so it won't move and wander off to clean some stuff. Sure enough, 5 minutes later, the engine just dies altogether.
1 pull later its running again.... idles fine, mid range fine, full power fine. 4 minutes later BAM dead - one cough and dies. gas in all the lines, not fuel starvation.... now i'm really scratching my head. i fire up the other engine and run it at full power for 10 minutes and no problems, but also no fuel bubbles in the line from the pump to the carb... this gets me thinking. i fire up the bad engine, and only at full power, there are little bubbles between the pump and the carb, that get worse as the engine runs longer. sure enough, the bubbles get pretty persistent, and you can even see a little vortex of bubbles getting sucked down into the fuel bowl... then the engine dies.
So, my attention is now turning to the engine and that port that drives the diaphram. perhaps the reed valve is not up to the task at full throttle? this is new territory for me, any advice would be appreciated. if the pump wasn't pumping as fast as needed, would it output bubbles instead of gas? this is the second and brand new pump and the engine dies the same way, so perhaps the engine isn't pumping the pump hard enough?
Tyler