Heater core replacement?

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FRANKENTRUCK

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How hard is it to replace the heater core in these trucks? Every mechanic I try will not touch it.
 

crazy4offroad

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Replacing a heater core on anything is not fun so I dont blame them lol but these can be hard if you have factory air and all the ductwork/plumbing in place. Older trucks tend to have brittle plastic parts and if they broke something and couldnt fix it parts may be hard to find/expensive. A regular non-a/c truck it would be a 2-3 hour job if you take your time and be careful not to break anything.
 

FRANKENTRUCK

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My truck has an AFTERMARKET AC unit in it that (of course) no longer works. Someone even reconfigured the glove box to accodomate it. I HATE it because it interferes with my original GM AC DELCO radio that I installed. I suppose the heater core will accompany a new AC unit someday too.
 

oneluckypops

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Replacing a heater core on anything is not fun so I dont blame them lol but these can be hard if you have factory air and all the ductwork/plumbing in place. Older trucks tend to have brittle plastic parts and if they broke something and couldnt fix it parts may be hard to find/expensive. A regular non-a/c truck it would be a 2-3 hour job if you take your time and be careful not to break anything.
Was there a difference on how they where constructed from 73-80 versus 81-87? I ask cause when i changed it on my 79 i was done start to finish in like 15 minutes. But my 85 was a PITA.

My truck has an AFTERMARKET AC unit in it that (of course) no longer works. Someone even reconfigured the glove box to accodomate it. I HATE it because it interferes with my original GM AC DELCO radio that I installed. I suppose the heater core will accompany a new AC unit someday too.

If you need any parts for that aftermarket a/c let me know i have a complete system that i removed from another truck
 

FRANKENTRUCK

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I was hoping to put in a OEM AC unit. Is yours all aftermarket? Is it functional? ACs are always the first thing to go in vehicles!
 

oneluckypops

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Mine uses an aftermarket compressor, Bracketry, Hoses, Condensor, and Evaporator. The evaporator box is right behind the glovebox, all the ducting ties into the OEM ducting for dash vents.

In theory the aftermarket A/C system SHOULD out perform the factory a/c system simply because the evaporator is located INSIDE the cab NOT under the hood in the engine compartment.

A/c is simply heat exchanging, which means when the evaporator collects the engine compartment heat aswell as the cabs heat, when in MAX position.

I was told the system was operational when i bought the truck, but all i can verify is that it had pressure, and the compressor does turn. I blocked off all the connections to keep dirt out of everything when I removed it.
attachment.php
 

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Stroked

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I think it took me around an hour and a half to replace the heater core in my old '86. And that was only because the blend door was broke and I had to take it out to fix it.

Everyone kept telling me it was going to be horrible, but it really wasn't bad at all. :shrug:
 

jake wells

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i got a 12 volt 5 amp aux heater in my truck mounted under the seat. it is in the middle. it comes in handy in the winter when i need a little extra heat i replaced the heater core in my truck it is a non a/c model and it only took me about 2 1/2 hrs and it wasn't that bad.
in my vent box i added a small square box with a door so i could place a drink or a food item inside to keep it warm in the winter.

works great for coffee
 

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Mine uses an aftermarket compressor, Bracketry, Hoses, Condensor, and Evaporator. The evaporator box is right behind the glovebox, all the ducting ties into the OEM ducting for dash vents.

In theory the aftermarket A/C system SHOULD out perform the factory a/c system simply because the evaporator is located INSIDE the cab NOT under the hood in the engine compartment.

A/c is simply heat exchanging, which means when the evaporator collects the engine compartment heat aswell as the cabs heat, when in MAX position.

I was told the system was operational when i bought the truck, but all i can verify is that it had pressure, and the compressor does turn. I blocked off all the connections to keep dirt out of everything when I removed it.
attachment.php


That system right there looks like it install to look OEM in the dash rather than an underdash unit. But by the ductwork and that blower motor, looks like it'll freeze your ass out of the truck too.
 

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I need to put a heater core in the 85 K1500 too. Maybe when I do it, I'll take pics and post up a write up. I'm not sure of the 73-80's are different from the 81 ups or not. We just might need to tech write ups on heater core replacement. Maybe even 4 cuz I know they are different for AC and Non AC trucks. I think the NON AC trucks are much easier to do.
 

89Suburban

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Whoever put one in mine left the heater box housing dangling off the firewall. Leaks hot air into the cab in the summer and cold air in the winter. Can't wait to crawl under there and fix that ****, yah right.

You can stick your whole hand in the gap. :shitsweak:
 

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***UPDATE***
Turns out that WAS a pain in the butt, even for my seasoned mechanic who does all my work. He had a devil of a time just loosening the bolts. It took him nearly 2.5 hours, but it is finally done.
 

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So what did he do? Just install the heater core? And that's for a NON AC truck. Imagine if it were an AC truck. Mega Bitch is all I can say. Fuggin Mega Bitch. Of course being broke from my neck to my ass doesn't help.

So what are you doing to your truck as far as HVAC? Installing OEM AC unit? Fixing the Retrofit AC or What? I noticed you're looking for an OEM AC/Heat/Defrost Controller? When I find that thread.....
 

FRANKENTRUCK

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So what did he do? Just install the heater core? And that's for a NON AC truck. Imagine if it were an AC truck. Mega Bitch is all I can say. Fuggin Mega Bitch. Of course being broke from my neck to my ass doesn't help.

So what are you doing to your truck as far as HVAC? Installing OEM AC unit? Fixing the Retrofit AC or What? I noticed you're looking for an OEM AC/Heat/Defrost Controller? When I find that thread.....

He simply installed the new one after practically having to Jaws-Of-Life the old one out (frozen bolts). I am looking for the equivilent of the heater controller in the picture MINUS the A/C option. I used that picture because the pictured controller seems close to the old unreadable one that was in my donor cab. I remember the old one having three options on the top lever but I have no idea what they were. Maybe they were OFF HEATER DEFROST, I am not really sure. My truck did not originally come with A/C so I am taking out the nonfunctional AFTERMARKET one first chance I get.
 

HotRodPC

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OK, I found your other thread that I meant to post in last night but went to check my supply and wasn't what you needed then forgot to post in it. Bummer, all my trucks are Silverado, all AC, AUTO, with PL and PW. All 5 of them are almost equipped just a like.
 

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