It won't run well until you purge it. You can't purge air out of the injector pump by hand pumping fuel through the system and opening the bleed screws. You have to crank it over until you put pure fuel through the injector pump. That is why I suggested giving the engine lots of throttle and then cranking it. If you have the rest of the system bled, cranking with the throttle wide open puts lots of fuel through the injector pump and flushes air out. Once the air is flushed out the engine will start. If you are really concerned about filling the exhaust system with water, then take the raw water pump impeller out and start her up. You can run for several minutes with no raw water without over heating. Once you get the engine running, put the impeller back and you are good to go