Heater Core Lifespan

[BMosely]

In most cars it is the external corrosion not the internal corrosion that kills the heater cores. Leaves, bugs, nuts, chipmunks, and water. Let copper stew in that mess long enough and you get a new air freshener along with wet carpet. Just pulled down our 68’ Coronet original air box. Semi disaster as expected but prior to pull down the core and evaporator passed pressure tests. The design of the Mopar box drives the primary air flow in front of the evaporator first, flowing thru the heater core for discharge to the cab. Hence the reason for that little fire wall valve to bypass the core. Now I get it. The good news is all the trash, nuts, straw, etc loads up on the evaporator. I mentioned water. The evaporator has a drain pan so moisture discharges vs standing and stewing. The heater core stays dry and trash free. That is how it makes it 50 years.

 

[BMosely]

A couple of my trucks we cleaned preemptively while still in the trucks. Not possible with the Mopar design. As a matter of fact, I may hardware cloth a patch inside the box just outside of the blower so that heavy debris can be cleared,

 

[Kilrbee]

In most cars it is the external corrosion not the internal corrosion that kills the heater cores. Leaves, bugs, nuts, chipmunks, and water. Let copper stew in that mess long enough and you get a new air freshener along with wet carpet. Just pulled down our 68’ Coronet original air box. Semi disaster as expected but prior to pull down the core and evaporator passed pressure tests. The design of the Mopar box drives the primary air flow in front of the evaporator first, flowing thru the heater core for discharge to the cab. Hence the reason for that little fire wall valve to bypass the core. Now I get it. The good news is all the trash, nuts, straw, etc loads up on the evaporator. I mentioned water. The evaporator has a drain pan so moisture discharges vs standing and stewing. The heater core stays dry and trash free. That is how it makes it 50 years.

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While I may disagree with your heater core theory, ( 99% of the time the corrosion is from the inside out) if the heater core in the pic was mine I would for sure re-core it before it went back into anything! while it may have passed a pressure test right now I do believe that the white corrosion showing means that it is short for this world, and being an A/C car it is a royal pain to do it again later...just my 2 cents...