heater core leak?

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Matthew Sermini

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Hey everyone i need some help. So i have a 1976 Plymouth duster. It originally came with a slant six and A/C. now i have a 340 in it with no A/C. I need help because i went to go clean dirt off of my passenger side floor mat and it was soaking wet with radiator fluid. it looked like it was coming from the A/C box up under the dash even though there is no A/C hooked up. it might just be running down the side. I'll send some pictures if anyone can help. i know the heater core is bad because the defrosters do not work but the A/C blows air. Also, do i even need the A/C box? if i have to take it get to the heater core is it worth putting back in? am i allowed to take it out for good? if anyone has done this or knows I would really appreciate the help. thank you.

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BTW radiator is already drained and glovebox is already removed. if anyone knows the correct heater core replacement i would greatly appreciate that as well.
 
I am going to take a wild guess that there was some antifreeze still in the heater core, and the core finally gave up and started leaking. The heater core and a/c are all in the same place. I would get a new heater core. How else would you defrost the w/s, or get heat. I know, you live down south and don't need it!
 
I am going to take a wild guess that there was some antifreeze still in the heater core, and the core finally gave up and started leaking. The heater core and a/c are all in the same place. I would get a new heater core. How else would you defrost the w/s, or get heat. I know, you live down south and don't need it!
well last week when i first drove it in the rain i needed to use a rag to keep wiping the windshield. i think the motor is toast as well because it didn't blow at all but the A/C vent was blowing.
 
Take a deep breath and accept the fact that you need to pull the heater box and replace the heater core. I've done it on an A body several times. It is something you could easily do in one weekend, or one long day.
 
CR9120, $68. Year One. You can probably get one locally, auto. parts store
 
That HVAC box will come out in about 15 minutes. It's not a world tragedy, I promise. I tell you what I would do. If you don't plan on putting A/C back on it, I would change it over to just a heater car. You'll need the correct heater only controls and the heater only box, but it will be much easier to work on and around in the future. JMO
 
Agreed, not much to pull it oit.

I did my 64 Valiant's heater core, cleaned all the crap out and replaced the gaskets in under 45 minutes. Out and back in. With hand tools. Granted, mine is heater only and a 64, but his is really not much worse at all. It's a really simple job. Certainly nothing to fret over.
 
Not sure on a '76. One hanger in the rt vent, controls and electrical wire, ground wire, 4 motor nuts and a screw at the tubes. Its out.
 
Heater core as mentioned has to come out. Depending on how quick you want it put back in, theres 2 options. Either have a rad shop repair your original(that's what I would do) OR buy a new quality one. That doesnt mean from Year One either. They are one of the most over rated and expensive "outifts". Look for a Spectra heater core, they are quality and lots of distributors.
Year One "issues"
Anyone else have trouble with Year One?
 
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In pre 73 models the firewall is different. To put in factory ac/ you have to cut away metal and add some holes. To remove factory a/c and install a heat only box you have to add filler metal back and plug some holes. I dont know if this firewall issue applies to 73 and later or not. I do recall several years ago a member had a tough time finding the correct heater core for his 74 model with a/c. Something about the tubes was different from other models. Good luck with yours.
 
So, don't just order one off of the inerwebb.
Call and verify the appliction A /C or non.
 
So, don't just order one off of the inerwebb.
Call and verify the appliction A /C or non.
i purchased one that will be here friday. 76 duster with A/C. ill probably take the box out tomorrow and hopefully get it put back together friday or saturday.
 
On my 72 B body it was more difficult with the AC heater box because of its size than a regular heater box. I ended up damaging a corner of the box. Mine got wedged between the trans hump and the passenger side. Just take your time and have a friend help.
If nobody has suggested it I would remove the front seats or seat. You'll thank your self later.
 
i ended up doing it by myself. it took a while but it wasn't terrible. I have now two issues. 1. the heat does not blow hot, and 2. i cant slide the switch from hot to cold air. it is stuck and wont go more than half way over to the cold side. the heater core does not leak now but those are my issues. also i took decent pictures during the process of taking apart everything so if anyone knows how, we could turn this thread into a pretty good how to for A/C cars because it was much more different than threads about non a/c car heater core removals
 
i ended up doing it by myself. it took a while but it wasn't terrible. I have now two issues. 1. the heat does not blow hot, and 2. i cant slide the switch from hot to cold air. it is stuck and wont go more than half way over to the cold side. the heater core does not leak now but those are my issues. also i took decent pictures during the process of taking apart everything so if anyone knows how, we could turn this thread into a pretty good how to for A/C cars because it was much more different than threads about non a/c car heater core removals

Sounds like the cable is out of adjustment.
 
i ended up doing it by myself. it took a while but it wasn't terrible. I have now two issues. 1. the heat does not blow hot, and 2. i cant slide the switch from hot to cold air. it is stuck and wont go more than half way over to the cold side. the heater core does not leak now but those are my issues. also i took decent pictures during the process of taking apart everything so if anyone knows how, we could turn this thread into a pretty good how to for A/C cars because it was much more different than threads about non a/c car heater core removals


Sounds like the cable is out of adjustment.


Or pinched somewhere...
 
I have a question i need to change my heater core and my car has A/C is there a special one for A/C or are they all the same for my 66 Dodge Dart
 
Take it out and compare to pictures of heater cores available on web sites.
 
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