I have a 76 Trojan 30' Sportfisher. The head was installed by the previous owner. He connected the discharge hose of the holding tank directly to the massarator pump then the pump to the selector valve. The pump will not run and the tank is full. My question is, will a pump out station pull through the pump impellers and suck out the holding tank? I'M fearfull that it will not and now I will have to figure out a way to empty the tank. Help Please!!!