Coolerguy1965

My 65 has been leaking ever since I bought it in October and my friend and I thought we had found the problem with the passenger vent window weather stripping and we replaced it but it still seems to be leaking and when I feel the carpet it feels really greasy maybe its because the carpet is old but I have no idea. Now I have another problem on the way home from church today the passenger side of the car on the INSIDE started leaking antifreeze underneath the dash right next to the wall I have no clue what could have happened there maybe a blown seal in the heater. Help?

mortman

check the hearter core and water lines through the firewall. Had same problem, heater core was leaking

Coolerguy1965

Ok thanks I'll do that and see what I can find.

JamesW

More than likely your heater core finally giving up the ghost. They are pretty easy to change out, and new cores are relatively cheap at Autozone.

Here's a photo of the heater box. You'll have to take it out as an assembly since the core is inside. The 4 screws holding the blower motor frame (inside the engine bay) and the cowl mount are the two attach points. The unit will slide out after that. Disconnect your heater hoses at the motor and pull them through.

1) Test your new heater core before final installation. Install one hose, plug the other port, submerge in water in the kitchen sink, and blow. Look for bubbles.
2) Replace your heater hoses to your motor at this time.
3) If you have time, order a heater box rebuild kit from one of the major mustang supply houses. It has all the seals and foam to rebuild the box and stop all the leaks.

Coolerguy1965

Thats awesome thanks for the help. Do you happen to know where I can find a diagram or a how-to on how to change out the heater core because I'm pretty new to all this and I am wondering if I should get a mechanic to do it or do it myself I am just inexperienced a little when it comes to these things and I don't really want to have the whole dash apart in front of me wondering where the heck everything goes. So if you could help it would be excellent.

65StangFB

When changing mine I didnt have to take the assembly out. If you remove the clips on the front of the assembly and remove the front of it, you can then get to the core. The only thing I had to do was remove 4 clips and disconnect hoeses. I think the core was <$20. Reconnect the hoses, place front on heater box and put clips on. This is all assuming they did it the same the entire year in 65. Let us know what happens.

Coolerguy1965

Ok thanks I will go and pick up a heater core probably on wednesday and get started on it then and I will let you guys know how it goes thanks for the help.

Just as an afterthought...could the core be leaking even if the heater is not on? It just starts leaking as soon as I fire the car up.

colostang

Try this link. Might help http://www.mustangmonthly.com/howto/5769/index.html

jlp66stang

Careful when you remove the clips, not to bust the fiberglass, pliers not screwdriver!

JamesW

That article from Mustang Monthly is great. It has all the key points. A couple of suggestions:

1) Buy a heater seal kit. They $10 from places like Texas Mustang and are well worth the effort to rebuild the box. It will seal better, be warmer in winter and cooler in summer.



2) Install a hot water shut off switch. There are two types...either lever controlled or vacuum controlled. I prefer the blastic vacuum controlled because they're less prone rust up. The great thing about these valves is that they allow you to turn the hot water off going into your passenger compartment, which will make a significant difference in cabin temp in the summer.

Here's a vacuum unit (mid 80s truck style)... you can see it in line, just before the hose goes through the firewall.


Here's a mechanical style valve:



3) Run the hoses neatly, not looped out over the fender. See photo above.