Thetford toilet cassette pump failure.

A couple of years ago our thetford toilet pump stopped working. I drained the tank and part filled it with hot water. Pump started and has been fine ever since. - worth a try but don’t use boiling water as the pump is only plastic.

The pumps are prone to seizing up and often all that is necessary is to access it and give the impeller a flick to start it working again.

YouTube has videos that will help.

Try reversing the polarity on the pump itself. Briefly and for three or four attempts cleared a sticky pump for us. It’s still going strong a few years later.

+1

Ours did just that, we followed a youvideo and the procedure is very easy even for a complete non technical person like me, gave the impeller a quick push and all was well.  

I suffered this. It was down to an accumulation of black gunk I think caused by pink fluid. Just used water since and it's been fine. However there is still black residue in there. Any ideas how too clear once and for all?