Drain Pump Issue

[Cubacheski]

Replaced a couple of cartridges today in the rear ballasts. Prior pump wasn't running. Replaced and it runs fine. Filled up ballast and did just fine. Switched to drain and it just ran with no water coming out. I had it in my slip but down in the water to fill. Wouldnt drain so I lifted the boat up on the lift and half way up it started pouring out the side. Draining just fine. Any thoughts why it wouldn't drain sitting in the water but it did when I lifted it ??

[gahvey]

since they are aerator pumps it was probably a priming issue. My guess is when you lifted it that it put just enough pressure into the pump to get it to flow. I have this issue on my boat sometimes too and it often times just requires me to move the hose down a little so it primes the pump. You also mentioned replacing the pump cartridges which means that you probably ended up draining water out of the lines...Now that you have drained once I would be interested to know if it drains on the water without issue.

[Cubacheski]

Thanks gahvey. I will let you know after this weekend. In regards to your comment about replacing the cartridge... I replaced it because the hard tank below the floor in the back locker as well as the extra bag would not drain. they were full of water when I replaced the cartridge. We will see. Thanks again for the suggestion.