I recently removed my hot water tank. there are connections that sent cooling fluid into the tank,, I assume that it created hot water when the engine was on, also there is a hose am addition hose coming off the cooling hose to a ,, I suppose a overflow tank . when I started the engine nothing came out. I plan on connecting the “in” and “out” of the cooling hose together and reconnecting to the over flow tank.. any suggestions ? the boat used to have a 3K gen set in the stern, which has been taken out. I believe the overflow tank was part of the gen set