Got this tip re pump rehab somewhere, used before and again the other day. All that Tofino sand really fouls things up. I used warm soapy water, cleaned well, dried the pump then sprayed silicone spray into the pump. Now both pumps are like new. I got the silicone spray from a dental office, where it can be bought, I 'm unsure. But I have enough for about 50 more pump rehabs if you need it and live in Nanaimo.