Heater Core Bypass?

My heater core has had a slight leak for the past 4.5 years I've owned it. I might do the bypass until the fall when the heat is needed again.
 
TJ4Jim said:
I really think you all are overthinking this, a piece of 1/2" copper tube and 2 hose clamps will do the trick.
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True enough, but then I gotta solder it together, blah, blah, blah. If it were $20, I'd think about it, but since its $10, I'll just go with the special hose.

Next dumb question: If I'm going to abandon the core and eventually replace it, why do I need to be concerned about capping it off?
 
Zorba said:
Next dumb question: If I'm going to abandon the core and eventually replace it, why do I need to be concerned about capping it off?
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You don't.

It would just be to keep critters out, or aesthetics, or being OCD for sport, or whatever justification sounds good for what is at its core a totally unnecessary act.

Personally, I liked critters.

;)
 
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Zorba said:
True enough, but then I gotta solder it together, blah, blah, blah. If it were $20, I'd think about it, but since its $10, I'll just go with the special hose.

Next dumb question: If I'm going to abandon the core and eventually replace it, why do I need to be concerned about capping it off?
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Bend the 2 hoses for a 3" piece of straight tube, $1 at the most. Worked fine on my son's TJ
 
derekmac said:
My heater core has had a slight leak for the past 4.5 years I've owned it. I might do the bypass until the fall when the heat is needed again.
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With a slight leak, what were symptoms, other than coolant leak, how did you know it was heater core? I've been chasing a leak for a long time and it's getting worse. Good pressure tests and so on. Any info would be helpful.
 
pagrey said:
Smell, fog on the inside of the windshield, coolant dripping from the drain on the firewall behind the battery, coolant in the passenger footwell, that's all I can think of.
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It's still hot here so I'm not sure if I'd get fig or not, idk. I haven't been using ac to see if I'm getting anything from HVAC drain, nothing. I've heard that any leakage from core would go out drain rather than into passenger footwell, but again idk for certain, but it is dry.
I lost 2.5 ounces of coolant yesterday driving 27 miles. Pressure tests (several), block test, compression test, nothing in oil. Radiator and water pump have less than 10k miles and appear good.
Despite everything appearing good i think its either the cylinder head leaking directly into exhaust or the heater core. I have a bad back or I would have already pulled the head myself, having to have a shop do it, I want to be certain. I took it to a shop, they did everything I did plus put a scope in to look above pistons. They would like proof of leak too....
 
pagrey said:
Radiator cap is good, especially the little spring and disc on the inside of the cap?
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I had a new Stant cap that was sitting on my shelf for a few years, put that on couple of months ago, old cap definitely had bad spring. Stant looks good but I did just get another new Gates cap delivered from Amazon that I'm going to put on. I have the stuff to bypass core but want to do one thing at a time to isolate. I'm deciding which to do first.

Edit: Bypassed heater, taking it for a test drive to make sure no hose leaks. After this next week I'll know if that's it or not.
 
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AZSobo said:
With a slight leak, what were symptoms, other than coolant leak, how did you know it was heater core? I've been chasing a leak for a long time and it's getting worse. Good pressure tests and so on. Any info would be helpful.
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Coolant smell when the heat is on, and the very odd coolant drip out of the AC condensation drain.
 
derekmac said:
Coolant smell when the heat is on, and the very odd coolant drip out of the AC condensation drain.
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That is about what I've come to realize would be going on. I've never seen anything coming out drain but that doesn't mean anything, up until recently I've been looking for wetness inside the jeep but after reading up on it and asking questions found out that isn't necessarily the case.
To find out for sure I bypassed the heater core last weekend, I should know soon enough if that is it or not.
 
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