270 outdrive not moving water on muffs.

I have a 79 Bayliner with an AQ120B and a 270 outrdrive. I just replaced the impeller. The old was demolished Im assuming on initial start up after winter storage. I cleaned all the debris out of the raw pump and associated lines. I also ran a rod up from the hole on the of the outdrive and down from the elbow where the z hose connects. All intake line appear to unobstructed. I plugged the hole on the lower unit and attempted to just run water up to the raw pump without the engine running.......no water to the raw pump and alot of water exiting around the muffs. Is there a better or more appropriate set of muffs for volvo outdrives? What is best for plugging the hole below the intake vents when running engine out of the water?

Update.....I changed the orientation of the cups on the muffs they were horizontal made them vertical putting the hose output right over the intake gills, used a couple long zip to make the seal a little better then plugged the hole below the gills now it pumps like a champ.