Changing the heater core anything I should do while its out? And is this spot on the coil ok

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Bullet Bob

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Like the title says, I'm changing the heater core out. While I have all of this plastic out from the dash is there anything I should do or go ahead and change? Going to be a few days since I tore up a couple pieces of the box in the engine bay since I missed 2 nuts and have to epoxy it all back together.

Going ahead and pricing a radiator and water pump since I've always been told when one of the 3 go the other 2 are right behind it.

Found a spot on the coils when I took it out the box. My brain says it's ok, but I dont want to put something messed up in my truck.

Does anyone have a diagram of where what line goes where on the plenum. One of the line just fell apart when you touch it and went in the box. Other than where it went in I have no clue what it attached to.
 
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chengny

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Like the title says, I'm changing the heater core out. While I have all of this plastic out from the dash is there anything I should do or go ahead and change? Going to be a few days since I tore up a couple pieces of the box in the engine bay since I missed 2 nuts and have to epoxy it all back together.

Going ahead and pricing a radiator and water pump since I've always been told when one of the 3 go the other 2 are right behind it.

Found a spot on the coils when I took it out the box. My brain says it's ok, but I dont want to put something messed up in my truck.

Does anyone have a diagram of where what line goes where on the plenum. One of the line just fell apart when you touch it and went in the box. Other than where it went in I have no clue what it attached to.

With AC or heat only?
 

Bullet Bob

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Guess you can say it has AC. They just removed the lines, compressor, and the condenser when they swapped the motor. Found a thread from 2012 that talk about the different lines going to the box/duct work. Believe the line falling apart goes to cowl maybe. Going to have to do some more reading and scratching my head. Only new problem I have now is the defrost door is now closed after I removed the screws to remove all the stuff that was inside the box,and won't stay in the open position when I push it there by hand. Found a dirt dobber near the size of my palm, 2 tire gauges, big metal dr pepper screw cap from the 80s and 6 cents inside. Been scrubbing this thing and still dont have it even resembling clean. Including a picture of the inside box my finger is pointing at the spot the line that was falling apart went. The defrost door that is now closed, the box with the squirrel cage and evaporator. Couple switches I'm assuming control my heat. Round one labeled heat rotates with 3 or 4 spots. The other is a plunger style. Wasn't planning on tackling the ac and heat controls until I got ready to replace the carpet and reupholster the seat. So I could have plenty of room to move around on the floor to deal with the bottom side of the dash
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chengny

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Guess you can say it has AC. They just removed the lines, compressor, and the condenser when they swapped the motor. Found a thread from 2012 that talk about the different lines going to the box/duct work. Believe the line falling apart goes to cowl maybe. Going to have to do some more reading and scratching my head. Only new problem I have now is the defrost door is now closed after I removed the screws to remove all the stuff that was inside the box,and won't stay in the open position when I push it there by hand. Found a dirt dobber near the size of my palm, 2 tire gauges, big metal dr pepper screw cap from the 80s and 6 cents inside. Been scrubbing this thing and still dont have it even resembling clean. Including a picture of the inside box my finger is pointing at the spot the line that was falling apart went. The defrost door that is now closed, the box with the squirrel cage and evaporator. Couple switches I'm assuming control my heat. Round one labeled heat rotates with 3 or 4 spots. The other is a plunger style. Wasn't planning on tackling the ac and heat controls until I got ready to replace the carpet and reupholster the seat. So I could have plenty of room to move around on the floor to deal with the bottom side of the dash
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Duh - I should have realized it was AC equipped (at least at some point in time). Heat only air handlers do not use vacuum lines - they are totally cable controlled. Below is some info to help you get started:

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BTW - is the AC type control panel still installed? Without that, I'm afraid you won't get very far on this repair. Should look like this:

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Bullet Bob

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Thanks that's a huge help. The original controls are still there. This was my grandfather's truck and I think he might have had it set up to just blow heat on the floor instead of defrost. All it did most of its life was get feed from the store, haul a few cows to auction once a year, and haul whichever cow was being a pain to the slaughter house to feed everyone. Planning on adding AC after several other things are done first, and would like to use the factory controls instead of aftermarket. Figured while everything was out go ahead and do what needs to be done to make it easier down the road, or have an idea of what I might need to have on hand when the time comes. By the way what repair manual is that out of?
 

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