Maybe this should be in the "Outdoor Gear" section???

Has anyone fabbed thier own heat exchanger for on board hot water? If so, any pics?! Doesnt seem like the most difficult thing but any pics, dimensions would help me out alot.

Or even a good link on a writeup would be great

Thanks

You got me thinking i could also build my own. Sounds to me like it is made out of a 2" brass pipe with one hot water pipe running through it and a second source water running through and coiled around the hot supply. Does that sound right. I also read that some how one could be fabed from a small trans cooler?

Sorry I am not much help. But I am going to keep searching.

RockJock

Actually what I've seen and would make sense is the rad fluid goes straight into the big pipe, and the small hot water pipe is coiled inside of it. It'd be nice to know exacty how long the coil and main pipe is - I would guess if its too big the water will get too hot <img src="/forums/images/graemlins/shiner.gif" alt="" />

I had the exact project on the bench some months ago, and have made a prototype.( I can't go too fast, the typing hurts my brain,from NYE festivities, 3.00pm 1/1 local time)
A 10mm (3/8") copper coil rolled around 2" steel pipe, has baffles in between to slow the coolant down, and is encased in a vessel made of 2"OD copper pipe. Thats the basic thing.
I made this and took some pics as I went, but this was before my digi-camera, so I'll get some scanned, and post them soon. I then encased the vessel in 90mm stormwater plastic pipe (with end caps) and filled between the two with an expanding foam sealant, for insulation.
I am a Plumber/Gasfitter, so this stuff was laying around in my garage, just waiting to be used.. <img src="/forums/images/graemlins/cheers.gif" alt="" />

You can controll the heat by fitting the heat x in the heater hose lines, after the dash control slide switch. Slide to hot, hot water will come out, over to warm, and the same thing. A 12 volt pump is also needed to push the clean water thru the heat x from the source (river, bucket,etc) Around 8 or 9 litres a minute is good.
When I actually hook mine up properly, I'll take more pics.

Well that set up would work alot better than what I was talking about.

Pics would be cool showing how you plumbed it into your system.

this is what I did. and have in my garage waiting for the final assembly of the other projects going on right now.
parts I got a radiator with the internal trans cooler built into it. when i bought my replacement radiator it was in there but plugged up. so I got some fittings and some water hose. I had a pump laying around. I got a short section of garden hose as well from an old one. I have a shower head on a collapsing rod from an old telescoping ice scraper,and some wiring. I also have a water valve just like in a sink for hot to cold adjustment. a few tees and some clamps and wiring.
parts list:
Radiator with built in transmission cooler $79 advance auto
12 volt 15gpm pump from northen hydraulics can't remebr what that cost it was purchased a long time ago.
shower head 5 bucks local hardware
valve from an old sink that had a hose connection on it freebie
old garden hose
garden hose repair kit 3 bucks
misc tees clamps and fittings from lowes 16 bucks

here is how I put it together. I have a garden hose with a filter on the end. I have this connected to the inlet side of pump
then I came out of the pump with a fitting and then teed it.
from one side of tee I went to the cold water side of sink valve that I mounted through the radiator support.
from the other side of the tee I went to the radiator trans cooler inlet then went from the tranny cooler exit to the hot water side of the sink control.
from the sink controller it has a standard garden hose connetor on it. to this I attached a short pc of garden hose approx ten feet.
to the other end of the hose I attached a connector to adapt the shower head to the garden hose.
the shower head is attached to the collapseable ice scraper handle with a u bolt.
the ice scraper handle extends out about 4 ft.
I drop it in the short section of tubing mounted to the radiator support extending the shower head about 4ft high from my radiator support.
I then mounted a small section of tubing to mount the handle to the radiator support.
my hot and cold adjustments are inside the hood so I have to lift my hood to use it but
I have to lift the hood to use it any ways because of the radiator support mounted scraper handle.
the shower head is the kind that bolts to a concrete wall with two little tabs and the pipe runs up the wall to it.
I dont have any pics of this but it looks like it will do just fine.
at 15 gpm I should have plenty of pressure and can control that with the valves.
if it gets too cold I just close the cold side increasing the flow through the hot side. and vise a versa
I can even just pump cold water if wanted.
I also was worried about water in the lines during freezes so I got another fitting to attach an air line quick connect to the system and blow all the water out of it.
I just open the vlve turn on the pump and hook up the hose.
I also have a bed mounted water tank that holds seven gallons of fresh water. I got that from a old cubby cabin boat.
when I had drum brakes in the rear I thought about running a line down to each of them to wash them out after the mud.
but went to disk brakes instead.
I hope this helps
I have electric fans on the radiator that are thermostatically controlled to kick on and off at 180 degrees. so it should stay pretty hot.

I also thought about the water not heating up fast enough to be useable, so I have plans if the first set up doesn't work, to run the hot line from the radiator to the tank in the bed and just put in a tee before the pump to pull from the tank letting it circulate until it is hot. then I have seven gallons to shower with along with the cold water flow.

and with what your talking about doing the dual lines one cold one hot teed from the pum would allow you to set it as hot as you want. even slightly warm water is better than nothing. they use what you are talking about in ski boats as well for water skier to warm up their wet suit before jumping into the cold water. they even work as a shower to warm up with after skiing in cold water.

a 12 volt pump
a switch with relay
an exchanger
two line for fresh water
two lines for radiator hook up on the hot outlet of the water pump
a shower head
and a set of valves.

now my brain is tired

Damn! I reckoned that I had put some thought into my setup, but I had to print your post out, and read it a few times to get a handle on it! Some differences in American and Australian names for various bits also did'nt help.

You say you have a sink mixing valve (known as a Flickmixer around these parts) so you mix the hot and cold water? Jesus mate, I'd end up staying at a motel!
Now if you can take a flushing toilet out in the bush, that'd be something! <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/cheers.gif" alt="" />

I'd like to see pics of both of these setups. I dont think the radiator setup would work with mine. My engine bay is packed including the the beefy AC condensor, oil cooler and trans oil cooler.

I was thinking I would put this unit inside the fender.