Hi, can anybody steer me towards some drawings for a hand operated boiler top up pump please. It will be mainly used for bench top work although I might put one in a boat to make it easier to refill the boiler at the lake side. Have checked my Harris book and a couple of others but they are all talking about engine driven pumps. I just need bore, stroke, lever lengths and a design for the non return valve for a manual pump. Cheers, Ian.