[Guy]

Guy, the valves on my 8V92 are further to the rear of the coach than the photo you show. They are close to the engine mounted fuel filter on mine.

Michael, Thank you for your response. Between you and Kyle, it makes things easier for me to understand.  I have two hoses from the side of the block, and tomorrow I will see if there are valves hidden down there. Because this coach has a marine water heater added at a later date, I have a "t" in one of the lines going down the frame.  Even if there are no longer valves, just water ports in the block, I am assuming that there will be no harm in just running a hose from one port in the block to the other port.  Tom has suggested that he had by passed his dash heat this way, as he has agua hot.I can live without scalding hot water out of the marine water heater after a day on the road for  the time being. 

I did discover an under the bed water heater/ furnace during  this search. Under the bed is a 120 volt 10 amp heater that we currently use, and this newly discovered engine hot water heater.