Kingham water pump

All ready to change the pump but it started to work again. Worked fine until I filled the tank and it stopped working again. I can hear the pump running slightly louder than normal but no water out of taps not even air. I drained half a tank of water and the pump is working again. In other words pump doesn't work when tank is full but works when tank is half full. Mystery?

That sounds as though your tank breather (air intake hole on top of tank) is blocked. If your van has a hole in the wall water inlet as well as the Whale inlet then take off the cap and try again. If you don't have the hole in the wall than locate the inlet solenoid and remove the pipe from the bottom of that solenoid. Either will let air into the tank to replace the water that is being pumped. If that currs the problem then it is almost certainly the tank breather being blocked. You will probably need to drop the tank to sort that. On my van I get a puddle of water from the breather when I totally fill the tank. Do you?

inspiredron wrote:That sounds as though your tank breather (air intake hole on top of tank) is blocked. If your van has a hole in the wall water inlet as well as the Whale inlet then take off the cap and try again. If you don't have the hole in the wall than locate the inlet solenoid and remove the pipe from the bottom of that solenoid. Either will let air into the tank to replace the water that is being pumped. If that currs the problem then it is almost certainly the tank breather being blocked. You will probably need to drop the tank to sort that. On my van I get a puddle of water from the breather when I totally fill the tank. Do you?

Cheers Ron looks like you have hit the nail on the head. Filled the tank with water until it overflowed through the breather and it is now working ok. I think the breather was blocked and forcing the water into the tank cleared the blockage. I am in Portugal at the moment and was going to get a motorhome repair garage to fit a new pump. Thanks Ron you have saved me about 200€.

Excellent! Well done and thanks for feedback.