17
Well the pump is all back together again now, and reinstalled on the boat yesterday. Turning it the other way up was slightly more involved than it should be on other boats as I have my fridge compressor mounted on the bulkhead and it gets in the way of the inlet hose. Without the compressor in the way you should be able to just turn it 180 degrees upside down and screw it back in the same holes. I had to glue another pad on a bit higher up, and it's also angled to give a better run for the hoses - see photo. When you turn it the other way up you will need to change the direction of pumping. You can either just switch the 12v wires round so the motor runs the other way, or you can turn the pump head 180 degrees. Switching the wires might sound easier, particularly as you may need to add more wire with the motor being further away, but it could cause confusion in future with the black supply wire connected to the red motor wire. Turning the pump head is just a matter of removing two nuts, turning it round and putting it back on again, so pretty simple.
One thing that I've noticed over time is that the system leaks air, so I have to prime the pump using the hand pump first otherwise it fails to suck the water up high enough to get to the pump. I think some air is getting in via the ballast/bilge changeover valve as you can see bubbles in the pipe, and also air is being drawn backwards through the Whale hand pump, and this is in spite of me installing a non-return valve in the line. Once it's sucking water it's ok, but it still slowly sucks the water back from the hand pump until after about 5 minutes it's just sucking air again and needs another few pumps on the handle. It takes about 20-25 minutes to empty the tank, but I seem to remember when new it took 15-20.
If you want any info about refurbishing the motor then let me know.
(For some reason the thumbnail photo is rotated 90 but it's the right way up when you click on it for full size?)