There was a Forum about this before but I can`t find it. My Thetford cassette stopped flushing I finally got round to getting it checked out. The pump was OK and the switch housing was alright as well. Inside the tank the cable from the pump runs (amazingly) out through the bottom of the tank. The trouble is it`s not enclosed in conduit and it`s pretty loose. My theory is that I have on quite a lot of occasions travelled without draining the little tank and the movement of the `van has moved the cable to and fro and now I have a broken wire inside the tank with no idea how to replace it. It is so tight at the bottom seal that if I managed to get the cable out I would never get the new cable back through it. Next Spring I am going to try and bring the cable from the pump out through the top of the tank and somehow get it back down to the Switch gear.
So my friends let this be a lesson to you, always drain your tank when travelling.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.