Finally took some pics of the onboard Jeep shower. You can see the heat exchanger mounted just to the right of the air filter box, right above the alternator. I don't have AC so I mounted it to the engine where that usually goes. The pump is in the back drivers side corner of the engine compartment on a small shelf, opposite the battery. I didn't take a picture of it, but it's your standard RV/marine fresh water pump.
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Here's a shot of the heat exchanger from the front. The heater line and fresh water input are on the back, and you can see the outputs here.
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The intake and output hoses feed through the grill. I have quick disconnects on the hoses so they tuck behind the grill when not in use. It uses a basic camper shower head with an on/off switch to control the flow.
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