Take the inlet pipe off the pump and blow back into the tank. It sounds like you got a blockage.

kenif said..
Don't blow - suck!!!!

your hull need cleaning

aus005 said..
Hull does need cleaning HG

kenif I mean with word like that
Aus005
if you have a small funnel pour some water back to the tank and quickly put your finger over it lower if below the tank it might make a siphon for you to get you up and running
It probably full of old Boag's beer cans and its blocking the out let
you dont need fridges down there in the winter months
I always wanted to put 44 gallon drums around Tassy and move it up the east coast a bit so it had a warmer winter

southace said..
Mine does the same when I run out of water. Seems to be a airlock. The only way I seem to be able to clear it is to try and suck on the tap until I get water and no air. You also might find it will pump hot water no problem. Switching from hot to cold a few times also seems to help.

well you been down in Tassy to S.A. you might boags blockage as well few empties floating around inside the tank

Thanks for the ideas guys
the pump is lower than the tank and it won't pump hot or cold water and nothing at foot pump just a lot of air noise