LARIAT 85 Posted December 9, 2019 Share Posted December 9, 2019 I think my heater core is leaking...again. My original one lasted for almost 30 years before it soaked the passenger side floorboard. This one has only lasted a few years, but it's not leaking inside the cab? There is a small coolant drip landing on the plastic inner fender on the passenger's side and then on to my garage floor. I can't seem to find an OEM Motorcraft replacement, which leaves me no choice but to buy aftermarket. And I hate aftermarket parts. So what are we using for replacement heater cores for a factory A/C truck? Link to comment Share on other sites More sharing options...
Gary Lewis Posted December 9, 2019 Share Posted December 9, 2019 Spectra Premium. Link to comment Share on other sites More sharing options...
85lebaront2 Posted December 9, 2019 Share Posted December 9, 2019 Spectra Premium. I have had excellent luck with AutoZone Duralast lifetime, they do eventually go bad, but for the time it takes to change one of these, I'll let them keep giving me new ones. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 9, 2019 Share Posted December 9, 2019 I'm not sure how a '85's heater core is mounted but unless the neck got rubbed through by the firewall I'd think it's a hose or clamp problem. All the seams are inside the cab, aren't they? Link to comment Share on other sites More sharing options...
Rembrant Posted December 9, 2019 Share Posted December 9, 2019 I'm not sure how a '85's heater core is mounted but unless the neck got rubbed through by the firewall I'd think it's a hose or clamp problem. All the seams are inside the cab, aren't they? On my 1984, everything is in the engine bay, but it is a non-AC truck. When my heater core leaked, it too dripped down on the plastic fender liner. The AC equipped trucks are quite a bit different though, and the heater core much easier to change....from what I've read at least. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 9, 2019 Share Posted December 9, 2019 I'm not sure how a '85's heater core is mounted but unless the neck got rubbed through by the firewall I'd think it's a hose or clamp problem. All the seams are inside the cab, aren't they? On my 1984, everything is in the engine bay, but it is a non-AC truck. When my heater core leaked, it too dripped down on the plastic fender liner. The AC equipped trucks are quite a bit different though, and the heater core much easier to change....from what I've read at least. Rick said "Factory AC truck" so I assumed it was like mine. I still don't understand how you can have a heater core leak without a windshield sauna. Link to comment Share on other sites More sharing options...
Gary Lewis Posted December 9, 2019 Share Posted December 9, 2019 Rick said "Factory AC truck" so I assumed it was like mine. I still don't understand how you can have a heater core leak without a windshield sauna. Good point. Any leak of the core itself would be inside the truck. I guess it is possible the leak could be where the inlet/outlet tube hits the body and it could run down the tube and drip in the engine compartment. But that would mean the seal to the cab would have to be bad. And it would have to be a slooooow leak. More likely it is the hose/tube seal that is leaking and dripping on the fender. Link to comment Share on other sites More sharing options...
LARIAT 85 Posted December 9, 2019 Author Share Posted December 9, 2019 I'm not sure how a '85's heater core is mounted but unless the neck got rubbed through by the firewall I'd think it's a hose or clamp problem. All the seams are inside the cab, aren't they? You know, I thought all the seams are inside the cab as well. But I checked the hoses and connections, and I can't find a leak anywhere. The only place it is wet is the outside of the plastic heater case, under the hood. There is a small drip there that lands on the plastic inner fender. Link to comment Share on other sites More sharing options...
kramttocs Posted December 9, 2019 Share Posted December 9, 2019 I'm not sure how a '85's heater core is mounted but unless the neck got rubbed through by the firewall I'd think it's a hose or clamp problem. All the seams are inside the cab, aren't they? You know, I thought all the seams are inside the cab as well. But I checked the hoses and connections, and I can't find a leak anywhere. The only place it is wet is the outside of the plastic heater case, under the hood. There is a small drip there that lands on the plastic inner fender. Just installed my core a couple weeks ago and I didn't like the look of how close the tubes were to the firewall (was clearance but not much) so I wrapped the tubes with some of the silicon repair tape to provide a bit of a buffer. But I agree - I can't think of anywhere else beyond the tubes + firewall or tube + hoses that would be dripping outside the cab. I don't know how often you drive it but maybe stick some tissues in various locations and monitor? Link to comment Share on other sites More sharing options...
LARIAT 85 Posted December 9, 2019 Author Share Posted December 9, 2019 Just installed my core a couple weeks ago and I didn't like the look of how close the tubes were to the firewall (was clearance but not much) so I wrapped the tubes with some of the silicon repair tape to provide a bit of a buffer. But I agree - I can't think of anywhere else beyond the tubes + firewall or tube + hoses that would be dripping outside the cab. I don't know how often you drive it but maybe stick some tissues in various locations and monitor? Just to be clear: if my [A/C equipped] heater core were truly leaking, there should be coolant leaking *inside* the cab on the passenger's side. Right? I just checked the box from the inside again, and it is not wet with coolant - at all. Am I barking up the wrong tree? Link to comment Share on other sites More sharing options...
Recommended Posts