Phantom coolant leak/heater core question

[89VertLX]

Hey all, my 89 5.0 has developed a mystery coolant leak. After I've driven the car and park it, I can smell coolant. It will leave a few drops on the pavement that seem to be about where the firewall is. I figured that it was the heater core, because this morning the windshield steamed up after I parked the car. But the passenger side carpet is dry as a bone. When a fox-body heater core takes a dump, doesn't it soak the carpet on the passenger side? I turned the heater control all the way to "cool" drove it again, parked it, and another puddle appeared. I put the car on a rack @ work and there isn't any place obvious that it is leaking from.

Any info is much appreciated!!!!!

--Sam in Denver
89 'vert LX 5.0 69k original miles. Bone stock.
99 SVT Contour. Not stock. <eg>

 

[87gtconv]

First signs is what U have followed by a soaked carpet in a few weeks. Good Luck!!

 

[newbee90gt]

i had a coolant leak but it was comming from the little hole in water pump it leaked but dried up from heat, spent a week chaseing it down...my.02 cents

 

[ALMOST STOCK]

I'm in the process of doing mine right now, believe me it's your heater core that's leaking.
AS 87gtconv give it a couple of weeks and it will be leaking on the foor.

 

[HISSIN50]

when heater cores go, do they leak outside the car? not being an jerk, just never seen/heard that. if the core leaking soaks the carpet, how does it also leak outside the car or in the engine compartment?

if its leaking on the pavement, i would check heater hose clamps and hoses and the TB (EGR) lines and clamps.
just my two cents worth.
good luck

 

[89VertLX]

Thanks for the input. I just bought the car last week from a local dealer. When I first test-drove the car, I noticed the A/C wasn't working, so the dealership had the A/C converted to R-134A before I bought the car. The dealer told me that when the A/C was converted (new evaporator, condenser, & compressor -- the full $600 job) the shop had to pull the dash out. I've been reading in the forums that having A/C makes the heater core swap a lot more difficult. Is there any way the shop might've damaged the heater core while they were working on the A/C? What do y'all think?

--Sam in Denver
89 LX 'vert 5.0 69k miles. Bone stock
99 SVT Contour. Not stock <g>

 

[lgil351]

there is a drain tube that runs from the heater core box to the outside of the firewall....if the core is bad and leaks it can drain out this tube which exits the firewall on the passenger side almost directly above the exhaust. hope this helps you out

 

[Michael Yount]

I think lgil351 nailed it - if the leak is small, the same tray that catches condensate off the a/c coil will catch it, and the tube that drains condensate will take it outside the car -- the same spot where the car drips when the a/c's on in the summer. As the leak gets worse, it can overflow the condensate catch tray, and that's when it soaks the carpet -- just like the a/c condensate does if the drain tube gets clogged up. Best to either replace it now (have fun - big job); or bypass it under the hood. If you go the bypass route of course you have no heat or windshield defrost capability - not sure that's gonna work if it's a daily driver with a good 2 or 3 more months of winter in Denver.

 

[87gtconv]

BTW, once it soaks the carpet good luck in getting that smell out or the stain it makes. After 4 years I just put in a new carpet and pad in when I redid my leathers!

 

[HISSIN50]

Igil and Herr Yount, thanks so much. i knew there was a tray but didnt know there was a drain for it (doesnt make sense to have a tray and not have a drain now, does it [i just said to myself]). thanks for the info.

for the time being, it might not be a bad idea to line the pass floor well in plastic or something along those lines. toss some Micro fiber towels on top of the plastic to try to catch/ soak up fluid.

89 Vert, you might have some luck talking to the dealer where you bought it. a bud just got a used stang from one of the Ford dealers in town. since buying it, he has made them eat a few repairs (new starter, and some other stuff). he did this weeks after he had bought it. worth a shot.
i have capped a few systems, as it is a pain on many cars to do the core. but, as Michael said, that isnt gonna fly too long in Denver. Harbor Freight sells ceramic heaters that plug into a lighter outlet (if it comes to that. hope not).
good luck and thanks for setting me straight guys.

 

[89VertLX]

Thanks for all the advice. I'm going to talk to the dealer where I bought the car and see if they'll do anything. I don't expect much -- I know they didn't make much $$$ on the car (convertible in Colorado in February = not much demand). Fortunately, I have a 4x4 that I use as daily transport so the mustang is basically going to be a fair-weather cruiser. I restored and drove a 1970 1/2 RS/Z-28 for a couple winters in Laramie back when I was in college. Even with snow tires mounted, it was a scary ride when the roads got nasty. I'm sure the mustang isn't going to be much better in the snow.

Again, thanks for all the info.

Sam in Denver
89 LX 'vert 5.0 69k miles. Bone stock
99 SVT Contour. Not stock

 

[cavallonero]

Hi ya Sam,
I live in Aurora and just did a heater core swap about a month or so ago.
Its not as bad as it seems. Ive heard it can be done leaving the dash in but I took mine out to do some other work. The whole dash comes out with simple hand tools and took me about an hour or so to remove it. The heatercore swap is straightforward and putting the dash back in took me a little longer (maybe 1.5-2 hours). Either way, it can be done in an afternoon.
Good luck,
Dave