Heating water under the hood

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Aequitas1916

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Hey everyone,

New to the forum, and I’ve got kind of an odd question. It’s *kinda* kitchen/cooking related, or at least it’s closer to that than anything else. Pretty much a variation of the engine grilling idea, only no food.

I’m looking for a way to heat the water for my coffee using the engine compartment. That way I can just hit the road/trail/whatnot in the morning and stop for a coffee break once the water’s good and hot.

I was thinking of suspending a tea kettle over the exhaust manifold with some wire, but I can’t seem to find any that seal tight to prevent exhaust fumes or whatever else getting into the kettle. Otherwise it would be perfect, since they usually have a pressure relief valve so it won’t blow up if it boils.

Any ideas?
 

jim lee

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Heat exchanger with coolant water? Just like your car's heater but liquid to liquid as opposed to liquid to air. Boats sometimes use this kind of setup.

-jim lee
 
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Logan_Gibson

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Water to Water heat exchange, I use one for my camp shower. It gets boiling hot if you don't have a mixing valve.
You don't need to wait long to get some hot water, It takes just two or three minutes for the Heat exchange to get to 140°
 
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Kent R

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Im with the Jet Boil idea, I leave mine in the jeep all time. If you want a good heat exchanger we have a club member who put the Glind heat exchanger under his hood and loves it.
 

Dustin03

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Hey everyone,

New to the forum, and I’ve got kind of an odd question. It’s *kinda* kitchen/cooking related, or at least it’s closer to that than anything else. Pretty much a variation of the engine grilling idea, only no food.

I’m looking for a way to heat the water for my coffee using the engine compartment. That way I can just hit the road/trail/whatnot in the morning and stop for a coffee break once the water’s good and hot.

I was thinking of suspending a tea kettle over the exhaust manifold with some wire, but I can’t seem to find any that seal tight to prevent exhaust fumes or whatever else getting into the kettle. Otherwise it would be perfect, since they usually have a pressure relief valve so it won’t blow up if it boils.

Any ideas?
Digging up an old discussion here, but this made me chuckle. I was never alive to see it, but legend has it that my great grandmother rigged up a dutch oven under the hood of their old GMC, to cook dinner on the long trek from Phoenix to Flagstaff. Before the days of I-17, it could take all day. But by the time they got to the top of "the hill" (as some of us locals call it), the smell of perfectly-done pot roast was wafting in from the engine bay.

On a more serious note, if you don't have an older rig, I think you'll be hard-pressed to find the room for anything like what you're talking about. And as a general rule, attaching anything with wire is probably not the best solution. If you manage to find the space in your engine bay, find a few existing attachment points to mount a bracket. If it's bolted in place, there's no chance of something rattling loose and falling into someplace it can cause serious damage.

Good luck in your project! I salute your pursuit of thermal efficiency.
 

Temudjin

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We have a heat exchanger system here in Aus that is normally used to heat water for a shower, you'll find it at this link. https://glind.com.au/store/heat-exchangers/glind-auto-marine-heat-exchanger/. These are plumbed into the engine cooling system and do not mix coolant with the water they heat. But to be honest you'd be better off to keep a Jetboil and the necessary makings in the vehicle.
 
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ArmyofMike

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I've always thought of putting a water container under my Jeep hood to get hot from the engine compartment. Not boiling, but hot enough to take a quick cleaning of the hot spots. I figure a water container under the hood could reach up to 80-100 degrees on a warm day. Not a hot bath, but a warm bath.

The issue is how/where to mount it especially since the JK doesn't have a lot of room under the hood....
 

TSnider

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I have a heater exchanger setup I built so i have a shower when hunting. It will in fact get water up to engine temp and its awesome. I use an RV water pump so I have some real water pressure. I do not having a mixing valve, so I just monitor the bucket of water until its at the temp I want, and then I shut the truck off. It works awesome, but if you pull water out of rivers like I do here in Colorado, you might not mix the water since it would technically be contaminated. (though I have read water above 135 for 10 minutes kills giardia, which is my main concern)

But I will say this, if your intentions are to wake up, start the truck and let it warm up, get the water hot and make coffee, you are going to be a lot faster using a JetBoil as mentioned above. I will forever have on demand hot water in any rig I build because its awesome, but I personally wouldn't use it for coffee because its more of a hassle. An inverter and a drip coffee maker might suit you better.

Having hot pressured water is amazing for blasting off the skottle, dishes and traction boards if you have used them. I have even dropped the water pickup hose into the creek and blaster the camp fire from 30 feet away to put it out before I continued on after a shower. Lots of little useful perks.
 
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Eric the Eric

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I love the idea, it had never occurred to me before. Though I did watch my grandfather fry an egg on a hub cap (cleaned off) on top of our '82 Toyota truck. That little 22re ran way too hot for it's own good.
 

DBAR

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We used to heat food up in the engine bay of our humvees. Guys would get very creative with stuff like that in the field. In my experience though, it wasn't worth doing over just using the MRE heaters for the same task.
 

Boostpowered

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Some wood stoves hve water heaters its just copper tube wrapped around the stove pipe with a resivor on top and a spigot on the bottom. Im sure you could do the same on your headers or further down the exhaust pipe. You can have the resivor below the coiled copper if you prime the tubing with water first and it will work as a thermo siphion and pull water upwards using the vaccum from the steam rising to pull more water in the tubes.
 

grubworm

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i'm thinking about doing an engine swap on my wife's jeep sahara... better performance AND a hot shower

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VI Overlander

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I saw this the other day and immediately thought of this thread:

Boom, gotcha covered! :D
we would use these on our snowmobiles all the time. I would put in day old hot wings and they could be piping hot for lunch. One day we brought buttered bread and cheese. At lunch we would make runs, using the EGT gauge to dial in our cooking heat for grilled cheese sandwiches.41D96691-FC3F-4FBD-8689-A3CEBF8C2275.png