u/Able-Masterpiece5206

So, I have a 1973 Chevrolet G30 van, with an RV body attached to it that was built by a yacht company. As a result, the water heater for the RV is a combination electric or engine coolant for when you're driving. It circulates through the hot water heater and creates a 6 gallon tank of hot water for when you arrive at your destination. The engine has a heater hose running off of the bypass on the water pump that has a t-junction that splits between the heater core and running back to the water heater. I'm doing some maintenance and I'm looking at these hoses, they seem to be complicated to complete the mission. Is there any reason why I couldn't connect the bypass outlet to the heater hose that goes back to the water heater and have the outlet come back around and connect to the heater core? It seems like it would be a much simpler layout than the way it is right now. It looks like the path would be: bypass outlet to heater hose back to the water heater inlet, from the water heater outlet back to the front where it would connect with the heater core and the heater core outlet would then run to the small inlet on the radiator. Am I missing anything? Thanks!

Ok, I am seeing diesel coolant preheaters on the market. I have a 53 year old vintage RV built by a yacht company, and it has a hybrid electric/ engine coolant water heater. It still works great, but I'm curious why I couldn't use one of the coolant preheaters to put into the loop to heat the water for the RV side? I'd really like to separate the engine side from the RV side, it runs 20 feet of heater hose.

Ideas? Thanks!