Novak Conversions Jeep Wrangler TJ engine mounts

Heater Core Advice

KC_Jeep

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Hi all, newbie and not someone who has spent time under the hood so please be gentle. recently got a 2005 Wrangler X, noticed heater was not working, live in Texas so not a biggie but went online and viewed some videos about flushing the heater core. Opened the hood and found this? I "think" this is where my input and return hoses should be connected BUT cannot find anywhere near the radiator that there are also open attachments.
thoughts or advice ?

IMG_9820.jpg
 
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Hi all, newbie and not someone who has spent time under the hood so please be gentle. recently got a 2005 Wrangler X, noticed heater was not working, live in Texas so not a biggie but went online and viewed some videos about flushing the heater core. Opened the hood and found this? I "think" this is where my input and return hoses should be connected BUT cannot find anywhere near the radiator that there are also open attachments.
thoughts or advice ?

View attachment 623426
I should add that I was getting an evap code, not sure if related
 
Much like yours, my 2005 Rubicon purchased a few weeks ago has no heater hoses connected to the HVAC core. Perhaps a cheap "fix" to avoid a costly leak repair or replacement. Since mine is highly modded and will be used strictly as a dedicated trail rig, no heater function isn't an end-all, however there is a side purpose of that which mine can't perform, i.e., modulating air conditioning temps from max cold to something less, since there is no warm radiated water to "blend" temps coming out of the registers.

I'm thinking I'll try backflushing the core through those disconnected hose fittings to determine if that results in leaks onto the passenger floorboard area. If not, I'll likely restore the hoses and functionality of the heater.
 
Much like yours, my 2005 Rubicon purchased a few weeks ago has no heater hoses connected to the HVAC core. Perhaps a cheap "fix" to avoid a costly leak repair or replacement. Since mine is highly modded and will be used strictly as a dedicated trail rig, no heater function isn't an end-all, however there is a side purpose of that which mine can't perform, i.e., modulating air conditioning temps from max cold to something less, since there is no warm radiated water to "blend" temps coming out of the registers.

I'm thinking I'll try backflushing the core through those disconnected hose fittings to determine if that results in leaks onto the passenger floorboard area. If not, I'll likely restore the hoses and functionality of the heater.

Mine will have the resistor replaced ASAP, as mentioned Texas and now summer. Only have the highest setting but it does blow cold thank goodness. May have to replace the blower motor as well as it does not sound happy to be only blowing at the highest setting.
 
When purchased 3 wks ago, my A/C was blowing barely colder than ambient, so I scheduled a freon evacuation and leak test, which revealed a leaking Schrader valve which was replaced along with fresh freon. Subsequently, it wasn't correctly cycling between vent modes, so investigation revealed a loosely fitting (expanded from heat cycles) vacuum hose/check valve at the intake manifold fitting. Its now cycling correctly and blowing cold enough to uncomfortably chill fingers on the steering wheel from the outboard dash vent. My fan on highest speed seems make more noise than pushes air, so position #3 is what I'm using, along with directing max cold temp away from my hands and face, once cabin temps drop to a comfortable level...
 
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however there is a side purpose of that which mine can't perform, i.e., modulating air conditioning temps from max cold to something less, since there is no warm radiated water to "blend" temps coming out of the registers.

It doesn't need hot air from the heater core to do that, the ambient air temperature will be warm enough.
 
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Hi all, newbie and not someone who has spent time under the hood so please be gentle. recently got a 2005 Wrangler X, noticed heater was not working, live in Texas so not a biggie but went online and viewed some videos about flushing the heater core. Opened the hood and found this? I "think" this is where my input and return hoses should be connected BUT cannot find anywhere near the radiator that there are also open attachments.
thoughts or advice ?

View attachment 623426

So, going back to my dilemma, I think this hose coming out of the radiator should go to the input in the first pic and then the outbound hose should then connect where this one is. Looks like a bypass was done at some point. My question is whether I am correct in the above and whether this has been causing any damage or issues (and could this be why I am getting an evap code?

IMG_9824.jpg
 
Hi all, newbie and not someone who has spent time under the hood so please be gentle. recently got a 2005 Wrangler X, noticed heater was not working, live in Texas so not a biggie but went online and viewed some videos about flushing the heater core. Opened the hood and found this? I "think" this is where my input and return hoses should be connected BUT cannot find anywhere near the radiator that there are also open attachments.
thoughts or advice ?

View attachment 623426

99% of the time if it’s bypassed it is leaking. Look for the heater hoses that have been connected together. The previous owner may have removed on hose and then connected the other hose to the fitting, so you may need one hose.
Evap codes are not related
 
From your most recent pic, it shows the heater core hose coming off the thermostat housing and routed to the radiator. This tells me your core is shot and needs replacing.

You may not think you need it operational in the summer, but you do. The extra volume it carries helps to cool it down a little.

Get on YT and watch some videos on how to replace it. It is not hard, just very time consuming and appears you are stripping your jeep. You can do it. Find a good video and follow it along pausing for you to keep in step.
 
For the evap code, make sure your gas cap is tight. It probably is so then I’d replace it. It’s a cheap test and may fix it
 
I've had mine for maybe a month and I just noticed the same thing. The hose to the heater core is just looped back to the thermostat housing. Like you in Texas, I am in NW Mexico and winters here are like spring in other places I have lived. I assumed that the heater core was compromised at some point and the P.O. just circumvented it. I don't think I'll miss it.

It's kind of embarrassing that I missed something like that in my initial inspections. Don't know that it would have been a deal-killer, but still.

Then, again, a too-close inspection on any 20 year old vehicle with 100,000 miles would probably scare anybody with good sense. Still, she's in good shape, considering.
 
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You may not think you need it operational in the summer, but you do. The extra volume it carries helps to cool it down a little.
....

I understand your reasoning, but in any but extreme circumstances, I can't see that that bit of extra volume would be that critical.
 
Around here the outside temperature is 110-118 through the summer, so even with no heater core any setting other than AC and Cold means hot air comes out the vents.

Same here. Even winter temps are moderate. Summers are brutal. This is why I am planning to have my hard top painted from black to light gray.
 
Many years ago on the local AZVJC there was a lot of discussion about a white heat reflective paint made specifically for that. Similar to how the FJ Cruiser tops are.
 
After the Second Performance radiator core (2 in 3 years) I ordered a Brass works core, hefty price tag but who wants to be pulling the dash every year and a half? The Brassworks core is a tank compared to the aluminum and plastic core.
Just installed it yesterday and still need to drain some coolant and re attach the heater hoses but I'm hopeful I'll never have to do another heater core
 
Novak Conversions Jeep Wrangler TJ engine mounts