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Heater Core Question

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Old 12-15-2015, 08:47 PM
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Originally Posted by cruiser54
Awesome, that's the same exact one I got from O'Reilly's
Old 12-15-2015, 09:14 PM
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So, what are you gonna do for instructions? Got a factory service manual?
Old 12-16-2015, 10:08 AM
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I have one downloaded on my computer, otherwise the haynes manual seems to have a pretty good write up on it.
Old 12-17-2015, 06:20 AM
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Originally Posted by austinjoe13
I have one downloaded on my computer, otherwise the haynes manual seems to have a pretty good write up on it.
Factory manual on your computer?

It leaves out 2 things. As it shows 3 retaining bolts on the inside, there are actually 4. One kinda in the rear with the threads facing you.

Something they don't address is the fact you're gonna have to do a little surgery on the foam pad at the firewall where the heater core pipes go through.
Old 12-17-2015, 08:53 AM
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I found a big bundle of PDFs a few years ago that had parts of the FSM in it. I'll have to find them.

What kind of surgery are we talking here?
Old 12-17-2015, 09:52 PM
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Originally Posted by austinjoe13
I found a big bundle of PDFs a few years ago that had parts of the FSM in it. I'll have to find them.

What kind of surgery are we talking here?
Razor blade to cut the foam piece so the heater core tubes can be removed while leaving the evaporator tubes in place.
Old 12-18-2015, 12:06 AM
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Originally Posted by cruiser54
Razor blade to cut the foam piece so the heater core tubes can be removed while leaving the evaporator tubes in place.
Can this job be done without opening the AC? It works really well; I'd hate to mess with it.
Old 12-18-2015, 06:03 AM
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Originally Posted by austinjoe13
Can this job be done without opening the AC? It works really well; I'd hate to mess with it.
No.
Old 12-18-2015, 09:45 AM
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Originally Posted by BlueRidgeMark
  1. It's a bad heater core. The hoses are outside.
  2. It's ugly. Full dashboard removal. Schedule a weekend.
a friend and I replaced his heater core and ac evaporator in about 3 hours never having done this before. I think saying it takes a weekend is a bit much. we even disassembled and cleaned the hvac box. it's really not a terrible job. we dropped the steering column and swung the entire dash out of the way enough to pull the box.

op: you might consider changing the ac evap too since you'll be in there.
Old 12-18-2015, 09:59 AM
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Have you checked this? It's the Heater and AC valve. It's plastic and gets brittle after a while and mine broke yesterday when my mechanic tried to tighten the clamp around the hose that goes to it because he saw a leak. When he took it out it was filled with gunk and wouldn't open the whole way to allow the heat to pass through. He replaced it 45 minutes later and the heater works at least 5-7x better than before and it blows more hot air than before. I don't know if it was brought up earlier on in the thread though. Cruiser54, input? (It's the black piece with the arrow that is on the passenger side of the engine block close to the heater core hoses.Attachment 280750 Attachment 280751 Attachment 280752
Old 12-18-2015, 10:48 AM
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Originally Posted by LiamLikeNeeson
Have you checked this? It's the Heater and AC valve. It's plastic and gets brittle after a while and mine broke yesterday when my mechanic tried to tighten the clamp around the hose that goes to it because he saw a leak. When he took it out it was filled with gunk and wouldn't open the whole way to allow the heat to pass through. He replaced it 45 minutes later and the heater works at least 5-7x better than before and it blows more hot air than before. I don't know if it was brought up earlier on in the thread though. Cruiser54, input? (It's the black piece with the arrow that is on the passenger side of the engine block close to the heater core hoses.Attachment 280750 Attachment 280751 Attachment 280752
Your pictures aren't working for me. If you mean the valve on the heater hoses, I replaced it last year after I broke it lol

I called pretty much every shop in town, I found two with an R12 machine, one had it in the shop lol. I'll be up there later today.
Old 12-18-2015, 11:08 AM
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Heater Core Question-photo949.jpgHeater Core Question-photo4294966309.jpgHeater Core Question-photo4294966732.jpgHeater Core Question-photo25.jpg hopefully they work this time. And these are the best pics I could take of it. Forgot to snap a pic of the one that broke and was removed. But a little (red?) tube attaches to it and is the vacuum tube that makes it open and close.
Old 12-18-2015, 11:09 AM
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Yep, fixed that last year. It's still good.
Old 12-18-2015, 11:14 AM
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Yeah. I was kind of happy it broke while I was at my mechanics shop because I got it fixed right away and he showed me the weird engine setup the Military Humvee has because he was working in one that had seen combat in Afghanistan and was on the show Wheeler Dealers. Friggin huge
Old 12-18-2015, 08:25 PM
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84 through 96 does not require complete dashboard removal.


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