I DEMAND a how-to write up on this!!! It’s mandatory lol. (Please!!!)
Ok I wish a took pictures when I was doing this but it is not to difficult to do its more like everything jeep related space is a premium.
I started out with a ten plate heat exchanger that I brought from Duda Diesel
https://www.dudadiesel.com/choose_item.php?id=HX1210
The rest is misc. plumbing fittings and hoses. I used 3/8 braided hose that I got from a Marine Store I sure you could get it from a RV store or online. I want it to be able to withstand the hot water temp and I thought that normal hose might not hold up to temps.
For those that don't know a heat exchanger works it kind of like this. If you fill a pan with cold water and put it on the stove and light the burner the flames don't heat the actual water. The flames heat the metal pan the metal pan transfers that heat to the water and heats the water. The with this type of plate heater exchangers works similar but instead of using flames it use hot water from the engine.
If you look at the picture you will see it as 4 taps,
1 is inlet for the 180 + deg hot water supply
1 is the outlet for the 180+ deg hot water.
1 is inlet for the cold water you are trying to heat (lake water)
1 is the outlet the hot water you have now created (your new shower water)
The water from the two systems do not mix, so the engine water is new depleted or crossed with your shower water.
So the system works like this.
I removed the battery and mounted the exchanger under the battery, there is a flat section of metal.
You cut the rubber hose coming from the engine that supplies hot water to the heater core in the cab and reroute it to one of the inlets of the exchanger.
You take the matching outlet and run a hose back to the heater, so you are just taking the hot water that supplies your heater and having it run through the exchanger first and than to the heater.
Than you supply the other inlet on the exchanger with fresh COLD lake, river water and then you run a hose from the matching outlet and that is now heated water and it becomes your new HOT shower water.
You will also need a pump I'm using a Flowjet 2.9 gpm RV pump to pull the lake water and pump it through the exchanger and out to your shower head.
I mounted my inlets and outlets under the hood, I bought a set of washing machine hose bibs because they were colored red (hot shower water ) and blue (cold lake water supply) so I would never get them crossed.
I carry a 20' supply hose that goes to the lake to and use a cheap garden flood outlet to act an inlet screen. I have not yet mounted my pump so I currently just use alligator clips to the battery
This is my attempt to use the cooler as a cold water supply, and then showing the pump. You can see the hose running along side the air filter box and then down next to the battery to the exchanger. At my first attempt the water was way to hot to use so I had to connect it to a tempering valve to be able to regulate the water temp. I used 2 hand held shower spray hoses and connected them together with a short 1/2" brass nipple to make it longer. My drawing is not the best but it give you the idea of plumbing.
