T&T: re Holding Tank

[H-J'S]

> I've now come up with a
> problem on my nearly new, to me trawler. The holding tank hasn't been
> pumping out properly. 
> This came to light on a three day trip where the toilet seemly blocked but
> was actually indicating the holding tank was full....

Hi Peggy and all those that answered. My thanks to you all. 
The problem was (I think as I still have to buy it) the impeller was
spinning in its bush. Enough to pump some but it started slipping under
load. After taking the outlet pipe off and prodding around with a bar the
contents proved to be liquid not solidified as I previously thought.

The vents were also 3/4+ blocked, rectified with a screw driver on the tank
vents and the hoses with air from the dinghy pump (good suggestion) finished
off with water from a hose on everything. One vent hose was also looping per
Peggie's suggestion so that was shortened.

The issue now is how (without a gauge) does one know when you've pumped the
tank before running the pump dry which obviously is what has caused the
problem in the first place, although I think it's been like this for some
time.

Rob Harrington-Johnson
Mariner 30
Sydney