Heater core leak? 89Crown Vic

[mfmagicmike]

Hi everyone,

I recently noticed liquid dripping from beneath the firewall where the heater core is installed, especially when I turn on the heat/fan. Off course, coolant has been disappearing mysteryously since then, needing quite frequent refills...

So here are my questions:
. Could the dripping simply be condensation from the AC?
. Is the AC hooked up to the heater core, which would make it impossible to service by myself?
. Are these leaks more likely to be core- or hose-damage related?

By the way, when I turn on the fan inside the car, the windows gets instantly fogged (lasts only a few seconds), no smell, no smoke.

One last thing: this (most likely) leak appeared after I flushed the coolant system with a chemical cleaner (well done), might have caused all the trouble. So think twice if You intend to do pour anything else than coolant into Your radiator!

Thanks for Your advices,


mfmagicmke

[gadget73]

The core is actually inside the car, so more than likely if it was leaking to that extent your carpet would be soaked. You'd also smell the coolant really strongly inside. I'd bet more on a leaking hose at the heater core connections than a blown core. If you're seeing leakage under the AC box, then that would likely be condensation. Condensation dripping is perfectly normal but only when the AC is running. Easy test, see what color the fluid is. Green and sticky/slimy is coolant. Clear is condensation.

No the AC is not plumbed through the core. Changing the core yourself is possible, its just a pain in the ass.

[86VickyLX]

I actually have a long ass write up for this too, if it is a heater core. If it's coming from under the hood, I'd listen to Thain, and check your heater lines mang, that chemical stuff might have eaten away at on of the lines. Run the car and check for dripping.

[mfmagicmike]

The core is actually inside the car, so more than likely if it was leaking to that extent your carpet would be soaked. You'd also smell the coolant really strongly inside. I'd bet more on a leaking hose at the heater core connections than a blown core. If you're seeing leakage under the AC box, then that would likely be condensation. Condensation dripping is perfectly normal but only when the AC is running. Easy test, see what color the fluid is. Green and sticky/slimy is coolant. Clear is condensation.

No the AC is not plumbed through the core. Changing the core yourself is possible, its just a pain in the ass.

Yeah it seems like a shit job, and I hope I won´t have to do it. I remember changing the temperature sensor, wasn´t so much fun (and that was only the tip of the ice(berg)core).

Are the hoses easy to reach from the outside, through the firewall?

[mfmagicmike]

86VLx is around here too!
Listen up, Masterclass is about to begin.

[86VickyLX]

Master I am not lol. It's just some stuff that I've dealt with in the past with my own car. The hoses are to the left of the upper intake, if you were standing in front of the car, looking under the hood. Check to see if they're leaking coolant. Mine sprung a leak once. What was funny, it would only leak when the engine was revved. At idle, the hoses wouldn't leak.

[mfmagicmike]

I actually have a long ass write up for this too, if it is a heater core. If it's coming from under the hood, I'd listen to Thain, and check your heater lines mang, that chemical stuff might have eaten away at on of the lines. Run the car and check for dripping.

I hope I didn´t blow my whole cooling system/hose connections. When the engine is hot, it smells like grilled coolant, and there is a yellowish residue on the right valve cover rim. Might be a second leak, I´ll have to check it out when the engine is hot&running.

[mfmagicmike]

The funny thing about the panthers is that once You´ve finished a job, another one is coming up - yet they (almost) never leave You stranded on the side of the road or break down.

[86VickyLX]

I hope I didn´t blow my whole cooling system/hose connections. When the engine is hot, it smells like grilled coolant, and there is a yellowish residue on the right valve cover rim. Might be a second leak, I´ll have to check it out when the engine is hot&running.

If your hoses are old, I'd replace all of them anyway.
No, that actually sounds like my problem with my hose. It didn't matter if it was hot or cold. When I revved it it shot out a small stream of coolant. You should try having someone rev it and you look and see if it's leaking any where when it's being revved. Stay your distance so your car doesn't spit at you.

Oh, when you say right, you mean the passenger side right?

[91waggin]

The funny thing about the panthers is that once You´ve finished a job, another one is coming up - yet they (almost) never leave You stranded on the side of the road or break down.

I definitely have noticed this. I was wondering if I was just lucky. (Knock wood)

[RunUoveR]

i used to have a TC that blew its core

the windshield foged up and green antifreez was dripping on the carpet.

[gadget73]

Are the hoses easy to reach from the outside, through the firewall?

Yes. The heater core connections are directly above the passenger side valve cover. Not sure what year you have, but you either have one S shaped hose that goes to a pipe running along the intake and one rubber hose up to the front, or two S shaped hoses to pipes along the lower intake. The bottom end of that S hose is a little awkward to reach but its not that terrible.


The endless cycle of repairs thing is just part of owning an old car. Eventually you'll have fixed most of the stuff thats going to break, and you'll be left with wierd random problems.

[86VickyLX]

Yes. The heater core connections are directly above the passenger side valve cover. Not sure what year you have, but you either have one S shaped hose that goes to a pipe running along the intake and one rubber hose up to the front, or two S shaped hoses to pipes along the lower intake. The bottom end of that S hose is a little awkward to reach but its not that terrible.

'89 Vic I remember the original hose clamps that Ford used. I hated those things. I think I had to cut them off, because they would not loosen.

[mfmagicmike]

I passed the last 48 hours on the coolant system. The hose clamps are a pain indeed. Especially the upper hose going to the heater core. Just too unreachable. Everything is hard to reach on the right (passenger) side. I tried to take the plenum out : merely impossible (for a day job) because of all the hoses coming out of it.
Getting the valve cover out: impossible because of the engine coolant line passing over it (steel). Well ingenieered! No nice & neat valve cover gasket swap today.
At least I think I found the coolant leak: the heater control valve was broken. I will order a new one.
Swapped the coolant hoses in the meantime. One day I will have to take care of the thermostat too (another gynecologists job: deep, narrow and with a lot of obstacles (hoses) on the way to it.

[gadget73]

The steel line doesn't need to come out to remove the valve cover. Pull the upper intake, and you can wiggle the valve cover out. Its not fitting out of there with the upper in place though. Upper has 6 bolts and only a couple vacuum lines involved. There are also the two small coolant hoses to the egr spacer.

The stock hose clamps are crap, and very difficult to work with. I'd strongly suggest replacing them with normal worm drive clamps. Use a 5/16 socket on them and a small ratchet instead of a screwdriver and you'll have a much easier time accessing them. The socket trick works on stock type clamps too, not sure what size they are.

Only 2 hoses on the thermostat, both of which you remove. Replace the small one while you're in there, you'll never get it to seal properly again if its original. Just cut the little one and get it out of the way. The upper rad hose should also get replaced if its original, just due to age. Ratcheting wrenches will help a lot to pull the thermostat loose.