Hi, I have a mercruiser alpha 1 gen 2 1998 4.3 vortex . When I put the muffs on I am not getting water to come up from outdrive through engine and back out !! I replaced impeller with quicksilver / mercruiser kit, everything included in kit, still no water, replaced circulating pump on front of motor, still no water, replaced thermostat, still no water, replaced water tube between upper & lower section of outdrive, still no water !! When i pull hoses off thermostat and ran garden hose through hoses (engine not running) water comes out as it should, so nothing is blocked !! HELP !!!!