yeah, has to be user added. and no. the cap on the transom plug was open. i will be removing this bastard of a set up prior to reassembly.
betcha cant guess why the heads are off :-}
as for sucking air? it is an alpha so wouldnt the suction be in the drive? i could see water shooting out of the transom plug.
depending on RPM, it could do both. If the impeller is pumping more water than the engine driven pump can move, it will shoot water, if the engine driven pump is moving more, it will suck air. Depending on your operating regime, and the water you boat on, you may want to just cap it off. Being able to flush without running the engine can be beneficial at times, especially if you are in muddy, dirty, or salty conditions. not having to push the water past the impeller can help keep crap out of the expensive bits sitting inside the hull......