On-Board Fresh Water & Hot Shower (in a Jeep Wrangler JK Unlimited)

[theksmith 3,827]

i made the mistake of using a random chinese brand of faucet supply lines for the hoses that connect my heat exchanger into the system, and they started leaking recently so i replaced them with new hoses from Lowe's.

 

the chinese ones had natural colored seals inside which seem to have melted away. i'll have to see how the black rubber in the new ones holds up to the heat. if these deteriorate too, then i'll just switch to barbed adapters and hose clamps.

 

here's an end that was connected to the heat exchanger, the seal is completely gone:

 

 

the seal in the other end was starting to come apart as well:

 

 

Edited April 15, 2022 by theksmith

[wj4play 4]

On 7/5/2020 at 8:51 AM, theksmith said:

a couple minor tweaks...

 

 

leaky flush tee

 

the Dorman flush tee i had installed as a fill/bleed port at the new high-point in the system was leaking a tad. i didn't like that plastic thing when i got it and had already purchased a metal replacement from For Seasons but just not gotten around to installing it.

 

leaky part:

 

 

replacement:

 

 

 

 

too hot!

 

after idling for a long time or doing a slow 4-low rock crawl type trail and then using the water, i was still getting an initial surge of scalding water. i talked about trying to insulate the supply line to prevent this before:

 

 

that attempted solution was obviously not working out, so my new idea was to re-run the supply line from the tank out along the edge of the Jeep, away from the hot "tunnel" area.

 

 

 

then route it up inside the passenger fender as far away from the engine as i could realistically get it.

 

 

 

i'm not sure if this is the final fix for the too-hot water - i still need to test it on a hot day after a long slow crawl.

 

other than those 2 minor things, the water system has been working great so far.

 

In regards to the scalding hot water, try using a mixer valve from the plumbing department similar to what they use in restroom faucets, it takes the hot line from the heat exchanger and a cold line from the pump outlet (cold) and you can adjust the outlet temp to the hose end. 

 

like this LINK

 

 

[theksmith 3,827]

3 hours ago, wj4play said:

 

In regards to the scalding hot water, try using a mixer valve from the plumbing department similar to what they use in restroom faucets, it takes the hot line from the heat exchanger and a cold line from the pump outlet (cold) and you can adjust the outlet temp to the hose end. 

 

like this LINK

 

 

 

thanks, see earlier in the thread - already have one. the problem i was having was that the "cold" feed line to it was supplying such warm water that it couldn't effectively mix the scalding water down to a low enough temp.

Edited March 2, 2021 by theksmith

[wj4play 4]

On 3/1/2021 at 7:50 PM, theksmith said:

 

thanks, see earlier in the thread - already have one. the problem i was having was that the "cold" feed line to it was supplying such warm water that it couldn't effectively mix the scalding water down to a low enough temp.

Ah, my apologies I missed that. love the build 

[theksmith 3,827]

i had mentioned before about the Jeep needing to get up to full operating temperature before the fresh water would get hot enough for a shower, which is very slow to happen if just sitting at idle (i.e. a morning shower after the Jeep's cooled down overnight)...

 

Joe at On Point Performance let me know that coolant isn't even really flowing much through the heater core until the thermostat opens up fully. he suggested i move the heat exchanger from being in-line with the heater core to in-line with the oil cooler, which does flow coolant even before the thermostat opens. it's the hard line that T's back into the heater core return line here in the middle:

 

 

for some reason Jeep decided that the soft line attached to that one should be 3/4" instead of 5/8" like the rest of them, so this turned into a minor project. but after a trip to Autozone and O'Reillys, the change is done! i still need to test it after the Jeep sits all night and is completely "cold" to see if it really starts to heat the fresh water before the rig gets up to full temp.

 

Edited May 13, 2022 by theksmith

[theksmith 3,827]

21 hours ago, theksmith said:

i had mentioned before about the Jeep needing to get up to full operating temperature before the fresh water would get hot enough for a shower, which is very slow to happen if just sitting at idle (i.e. a morning shower after the Jeep's cooled down overnight)...

 

Joe at On Point Performance let me know that coolant isn't even really flowing much through the heater core until the thermostat opens up fully. he suggested i move the heat exchanger from being in-line with the heater core to in-line with the oil cooler, which does flow coolant even before the thermostat opens. it's the hard line that T's back into the heater core return line here in the middle:

 

 

for some reason Jeep decided that the soft line attached to that one should be 3/4" instead of 5/8" like the rest of them, so this turned into a minor project. but after a trip to Autozone and O'Reillys, the change is done! i still need to test it after the Jeep sits all night and is completely "cold" to see if it really starts to heat the fresh water before the rig gets up to full temp.

 

 

well this change did seem to get the water warming up faster on a cold start.

 

this morning the ambient temp was about 75* and the Jeep said coolant temp was 87* on startup. i filled the fresh water tank with filtered hose water (which was slightly cooler than ambient). the Jeep itself warmed up to 160* in about 5 minutes and at that point it would heat the fresh water to a tolerable lukewarm feel. 

 

before this plumbing change, the fresh water would not really heat up much at all until the Jeep hit around 190* or more  - and it usually requires driving around a little to get it up to that temp.

[curt-t 1]

On 5/11/2022 at 7:44 PM, theksmith said:

to in-line with the oil cooler, which does flow coolant even before the thermostat opens. it's the hard line that T's back into the heater core return line here in the middle:

I have never worked with tubing like that (I'm not sure which line it is in the picture). Do you need to use cutting and flaring tools?

[theksmith 3,827]

Just now, curt-t said:

I have never worked with tubing like that (I'm not sure which line it is in the picture). Do you need to use cutting and flaring tools?

 

all of those aluminum hard lines turn back into rubber hoses near the back of the engine, and they just have typical constant-tension hose clamps holding those on. there is a slight pucker/barb at the end of each hard line. i just unhooked the existing rubber hose and then re-joined to it with a double barbed connector.

[theksmith 3,827]

my existing pump and sprayer nozzle work well for showering or rinsing off muddy feet. but due to the pressure buildup from the on-demand pump, the setup wasn't great for getting just a small amount of water for something like wetting a toothbrush. it would also waste a lot of water if i locked the sprayer in the ON position for the common task of washing my hands.

 

so, i've added a rear faucet that uses an additional much smaller water pump that is activated with a switch (instead of being on-demand).

 

 

 

the swing faucet itself is meant for a wok or other commercial grill. the photo above shows it swung out to fill a kettle, and below is the "stowed" position. i use a small piece of velcro to keep it stationary so it doesn't end up rattling against the rear window.

 

 

 

it's mounted to some of my existing contraptions (the spare tire hoist and ham radio antenna bracket).

 

 

with the tailgate closed you can barely see it tucked in behind the spare.

 

 

it will also swing out past the tailgate for washing hands or to rinse something when the slide-out tailgate table is deployed.

 

 

the new tiny 12v pump was mounted inside the tailgate, behind the interior exhauster vent.

 

 

 

a 3/16" I.D. silicone hose runs down to the same water tank used for the shower and connects to the existing line with a brass tee.

 

 

the pump activation switch was placed on a new switch panel i created on the tailgate vent.

 

 

the faucet switch is a 3 position, ON/OFF/TRICKLE... "ON" runs the little pump at it's full 12v rating which is pretty low-flow but can still fill a pot quickly enough to not be a PITA. the "TRICKLE" feature drives the pump via a 5v DC voltage adapter so that it flows even less. this setting is perfect for rinsing hands without wasting water.

 

 

Edited March 27 by theksmith

[shellback91 1,731]

 

Nice set up.