[C320-list] Water Heater By Pass

[Dave Hupe]

 Christian - I assume you are talking about placing valves on the fresh water part of the water heater and leaving it drained, not on the engine-related hoses.  There should be no impact to engine cooling.  However, I do wonder if the water heater would corrode internally without fresh water in it. 
My boat's water heater had gone bad and been removed by the previous owner.  The hosing had been connected as a loop where the heater had been removed.  I had to replace my engine water pump that seized completely in my early boat ownership.  When I replaced that pump, I did not reconnect the hosing to/from the water heater.  I disconnected it completely, coiled it up if a future owner wanted to ressurect  the system, then I placed a very short loop of new heater hose on the pump in/out nipples. 
Dave Hupe
1994 C320 (#32)