Heater core problems.

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good times

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lorne
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85
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k10
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I just bought an 85 k10 a couple weeks ago. When i tried to use the defroster my window fogged up even worse and wouldn't clear. It got to the point that i had drops of water running on the inside of the window and i had to use a rag to clear it off enough to see. I am pretty sure it is a leak in the heater core but I cant smell coolant. Any ideas?

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MadOgre

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I would say it is a leaky heater core. I think I picked mine up for $60 just like new rebuilt.

Plan for a whole day to do it. Its not difficult but can take a bit to figure out. Also wash up all the plastic with soap and water.
 

datto62073

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i did mine in just a few hours but i have no AC either. its not to hard just time consuming. a core from O'reillys isn't to terrible and they work pretty damn good. i have one, because i work there, and although a touch smaller than the OE one, works excellent now that i have burped the system.
 

highdesertrange

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have you guys that have replace your heater cores notice the ones everybody wants to sell you don't fit right. I had to do mine last year. I couldn't find one that fit correctly, they were all loose. they were all slightly smaller and I tried everyone. so I finally took mine to my radiator guy and he built me one. it fit perfect. just wondering. highdesertranger
 

350runner

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I got a 4 seasons core cut the box open from inside and was done in an hour...

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highdesertrange

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yeah but did it fit right? is it loose? the four season one I got was like all the others, didn't fit right. highdesertranger
 

350runner

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yeah but did it fit right? is it loose? the four season one I got was like all the others, didn't fit right. highdesertranger
Yea mine fits good.

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highdesertrange

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so it wasn't loose once the straps were all tight. do you have ac? mine doesn't maybe that's were the problem lies. highdesertranger
 

350runner

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Yes I do have AC. :)

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Casper

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I have an '84 3/4 ton and it had a leaky heater core from the day I bought it. I can't remember how long it took, but it wasn't that tough of a job. I remember it being tight, but not difficult. Check your padding up under the dash and see if it's damp. That will tell you quite a bit.

ETA: Yes, it has A/C.
 

towjoe

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I have used a few 4 season ones. they fit decent. It is less than a hr job if the bolts stay in housing when removing nuts on outside of firewall. Ac heater core is not much different to change than a non ac on, just have to hunt alittle harder for the nuts on engine side of firewall.
 

MadOgre

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I have A/C and it fit really good but it was a rebuilt core which in my opinion is just as good as a brand new one. Same goes for rads I will always just have the old one refurbed its just as good as new but cheaper and no fitment issues.
 

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