Broken AC. Now what?

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jerula

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I am renovating the cabin of my 74 truck. Today I found out that the truck was born with A/C, but a previous owner removed some of the parts. I don't know all the English names for them, but the silver cannister in the engine room is missing. There is nothing inside the big plastic box also in the engine room. The big collector box in the cabin that houses the heater unit (the heater housing?) is in poor condition. The opening that should go to the driver left side duct has been sealed off. The main opening in the collector box (that should go to all the ducts) has been "sealed off" using a big nail that's been jammed into the mechanics. The duct that sits on the front of the heater housing and connects to the upper channel duct is missing. No idea where I can find a new one. Also the driver left side duct and all tubes are missing.

Now, I am on a budget so buying a completely new A/C is not an option. Besides, I live in Denmark and heating is more important than cooling and the heater *does* work but I am missing the above plastic parts. So, what would you guys do if you were in my shoes?

Alternative - to just remove everything. Close the firewall hole with a plate. But then what should I do with the coolant hoses? Would this even be a good idea? .. I am reluctant to go that way. Some ideas or maybe even somebody who knows where I can source the missing parts, would be greatly appreciated.

I've attached a few pictures of the heater housing box so you can see it and have a laugh.

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Rickf

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You can loop the coolant hoses until the parts are located. If you really don't need a/c, I would search for a non a/c heater assembly.
 

jerula

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Thanks Rick. That might be a good way to go about it.

I spent a lot of time trying to understand what I need to do to rebuild this into a non A/C solution. The piece I posted pictures of to take one - what is that port opening on the side (the passenger facing one). On mine, it is locked into place by a big nail. I have not idea how this should work and if I should expect this to work as it is. Where can I find information/documentation on what the full non A/C system on my '74 should look like (taking into account it's originally with A/C if possible).

Last night I fell asleep with the Haynes manual over my head trying to find answers :D
 

Rusty Nail

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Alternative - to just remove everything.

I think this is a terrible idea and do not consider this a viable option. Well, sure it's viable but it's also completely unreasonable to me. Looking at the picture of the heater box? **** man, that's workable and based upon your posts I believe that IS the best place to start.
You could have the heater back in no time and probably only need to buy a heater core. I think they are pretty cheap and yours may not even be broken! It is - but it could not be! Lol :(

There are a couple of different vent pieces that attach to that box..it's really not a big deal and you may be making a mountain out of a mole hill.

See the firewall side studs hangin out of the box? All you need is a couple of correct threaded nuts to get started reassembling that into the truck.
It you remove it all you will devalue the truck more than it costs to fix in my opinion. Plus it will suck and you'll regret it.

You really do not have to have ANY air conditioning parts to re-instate the heater and DEFROSTER. It's really just some plastic vent parts. Not a big deal at all.
Relax!
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Step 1. = find three nuts to match those studs. The other corner looks like it may be broke but no need to focus on it right now. We're gonna mock it up first and we could simply zap a wood screw in it... It'll be fine... ;)

Also the heater core isn't worth gambling on. I suggest a different one.

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First one I found as example. Again, no need to focus on it now.

And for Pete's sake , wash that deal man. Clean it up real good. You could remove the Heater core if you wanna look closer at it cuz the backside will need cleaned bad too. Clean it in and out like the Board of Health!

Clean up your firewall mating surfaces on both the box and in the truck. It'll probably seal up with silicone or other caulking. Again, not a big deal. These trucks are simple to work on - you don't gotta be a professional mechanic!

P.S. pliz include pix of the Rusty Nail! :headbang:

You got any more parts to show? We're gonna need more parts...see this deal though?
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Don't break it. That deal is actually pretty important and you've got one! Installed even! This is gonna be a cinch. :waytogo: that door pushes open and close...but don't mess with that thingy!
 
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SirRobyn0

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I would vote for either fixing the heater part of the existing unit, or finding a non-A/C unit to put into it, but to be honest I would use the unit you have just because you already have it and it is rehabable.

If you decide to pull it all out, you going to have to buy an universal aftermarket heating unit and it's going to be a pain in the ass to install. You can not go with out heat period (unless you live somewhere hot and dry). I hate to even admit to this but for one winter about a million years ago I had an late 70's Ford Courier that was a complete pile. The heater box was completely missing from the thing and driving it in the rain was a nightmare, below freezing even worse. You couldn't keep the windows clear enough to see out of. For a while I used a portable propane heater, but the moisture from that thing made it worse. The only thing that kind of worked was a 12 volt fan, it made me feel colder but directing it at the windshield helped to keep it clear in the rain. Please do not consider going without the heater box long term.
 

gotyourgoat

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I think this is a terrible idea and do not consider this a viable option. Well, sure it's viable but it's also completely unreasonable to me. Looking at the picture of the heater box? **** man, that's workable and based upon your posts I believe that IS the best place to start.
You could have the heater back in no time and probably only need to buy a heater core. I think they are pretty cheap and yours may not even be broken! It is - but it could not be! Lol :(

There are a couple of different vent pieces that attach to that box..it's really not a big deal and you may be making a mountain out of a mole hill.

See the firewall side studs hangin out of the box? All you need is a couple of correct threaded nuts to get started reassembling that into the truck.
It you remove it all you will devalue the truck more than it costs to fix in my opinion. Plus it will suck and you'll regret it.

You really do not have to have ANY air conditioning parts to re-instate the heater and DEFROSTER. It's really just some plastic vent parts. Not a big deal at all.
Relax!
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Step 1. = find three nuts to match those studs. The other corner looks like it may be broke but no need to focus on it right now. We're gonna mock it up first and we could simply zap a wood screw in it... It'll be fine... ;)

Also the heater core isn't worth gambling on. I suggest a different one.

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First one I found as example. Again, no need to focus on it now.

And for Pete's sake , wash that deal man. Clean it up real good. You could remove the Heater core if you wanna look closer at it cuz the backside will need cleaned bad too. Clean it in and out like the Board of Health!

Clean up your firewall mating surfaces on both the box and in the truck. It'll probably seal up with silicone or other caulking. Again, not a big deal. These trucks are simple to work on - you don't gotta be a professional mechanic!

P.S. pliz include pix of the Rusty Nail! :headbang:

You got any more parts to show? We're gonna need more parts...see this deal though?
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Don't break it. That deal is actually pretty important and you've got one! Installed even! This is gonna be a cinch. :waytogo: that door pushes open and close...but don't mess with that thingy!
There is a lot of useful info in this post but I cannot like it because of the suggestion to use wood screws.

Stop it.
 

jjester6000

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I'd duct tape over where the condenser goes, put in a new heater core and call it a day (I literially did exactly that on my '74 GMC earlier today except mine doesn't have A/C).

If it were my truck in Illinois I'd be trying my dammed best to fix that A/C, but I guess that A/C is not really that needed in Denmark (it can get up to 110 F in the summer and down to -20F in the winter).
 

Rusty Nail

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There is a lot of useful info in this post but I cannot like it because of the suggestion to use wood screws.

Stop it.

LoloL

I don't think the self trappers are gonna be the best bet into that plastics. Don't you agree he'll be better off with the big thread of a drywall screw or similar? Needs bigger wood screw thread to get a better bite. :)
 

gotyourgoat

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LoloL

I don't think the self trappers are gonna be the best bet into that plastics. Don't you agree he'll be better off with the big thread of a drywall screw or similar? Needs bigger wood screw thread to get a better bite. :)
Nah **** wood screws, couple tubes of window and door silicone should do it....maybe some tape or flashing to help mould depending how it goes. You wanna get ghetto fancy, go get a case of rtv.

Just say no to wood screws.

Really though just fix it right or make it so you don't do damage so you can fix it later, ie tape or turn the heat up. Wood screws cause more problems than they fix unless there's a 4x4 post or deck involved.
 

Rusty Nail

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It don't matter anyways, reckon OP done ghosted. :shrug:
He was gittin hooked up too!
He conveyed a sense of urgency and then Friday night...? He's prolly drunk or somethin.
I bet he wakes up and realizes he actually has some wood screws and maybe I gots a pritty. gud. idear...litle dab o sillycone and voila!

Fixed. He dont really even got to have the other vents/ducting if hes got the other side of that box.
You could fab a workable part out of SHEETMETAL with scizzors and make it function as a defroster...

Man these trucks are too cool!

Maybe he yoinked it all out already and now he's embarrased.
Or maybe hes the source of the problems.

Didnt those dudes make Saabs? With the moving headlights and ****..mmwhat could go wrong?

Lololo wtf u doin with a 40 year old chebby truk anyways old boy?
o_O
I like this thread tho. Maybe he'll show back up!

:badger_1:
 

jerula

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This is absolutely fantastic. Exactly the kind of help I needed. Thank you so much.

So, what I gathered from this.
- I should keep what I have and focus on getting the heater back to running condition. - Source the missing pieces and a new heater.
- Forget/Ignore anything A/C related for now.
- Get a A/C delete unit - one that allows me to keep the blower of course (it's christmas soon - good to have something to wish for)

First. I need to get a better understanding of the heater housing (in lack of a better word for it). The big vent that was locked with the nail. How is it supposed to work? There is no wire going to it or anything. So, is that as expected? So in short, it should not be connected to anything, right? When I removed the nail, the vent returned to middle position. It moves firm but smoothly, so is it safe to assume this works by vaccuum somehow??? I take it, it's the duct that should send air to the vents in the cabin, right?

The missing screw you mention is there. I left it screwed in where it should be - so I wouldn't loose it :)

Notice that the small end of the housing has a rubber thing screwed on to it. I guess this is the channel for the drivers left side vent, that has been closed (poorly) by somebody. Is that correct?
I have attached a picture of what I have - the heater housing, the upper defroster y-piece and the collector piece for the cabin vents. Next I found a diagram over at LMC truck and indicated what pieces I believe to be missing. Let's forget about the driver left-side vent for now. Some of these parts are not available at LMC and I tried to find them elsewhere, with no luck. Specifically the piece that connects the heater housing with the cabin vent distribution channel.

First. A nice clean housing. When I replace the heater, I will clean the inside. Notice I removed the nail and the vent is now half open:
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This is what I have:
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.. and of course the vents in the dashboard.

This is the nail I was talking about:
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This is the left side of the heater housing. Looks like somebody decided to remove the channel to the driver left side duct. No idea why it is done like this with that long pin??? it looks like something is being held on the inside? Didn't want to disassemble this until I hear what you have to say.
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Here I have marked what I believe is missing:
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Looking forward to see what you make of this.

Thanks.
Jesper
 
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Rusty Nail

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Gimme a couple of hours..that's plenty of time to upload an underhood pics. :waytogo:
Let's see the truck!

I'm on the Goats lately. :shrug: You never heard of em but that's an eight piece band...making that music.It's not electronic.
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*edit*

Ugch @ work all night. Hopefully its slower than last.

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That under steering column tube (FAR LEFT) is fed by the homemade block off shown here.


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That's not factory and was likely blocked off because it made hot air. Lots of it too.

I was just doin all this in my truck, cant be much difference to '74 but I dont know for certain. Too bad you get to skip out on the wood screw school, they are a squarebody rite of passage it seems. Maybe we could find another spot for one (or some) later on. No worries!

It might help if there were pictures of the underhood and truck to look at. Maybe they could refresh our memory...:hmm:

See the ******** P.O. did rather than fix it? Sucks undoing that stuff huh?

Gotta give the people what they want Jesper and we want more pictures. :Big Laugh: it's a small price to pay but you first huh?:baby: You'd think one of the other thousands of readers would kick in - but they dont. They are lurking in the shadows waiting on us to say the wrong thing. Or they dont know.. SO! No other replies is actually good. Rest easy.

Might as well coff up some more pics and quit screwin around new guy.. you want in the club or what?;)

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jerula

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Absolutely. I am happy to oblige :)

Not exactly sure what parts of the truck you want pictures of. Here're some. The truck was born with A/C since the outer housing is still there - but it's empty as you can see.

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jerula

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ps: As for the wood screws ... I am sure we can find a use for them when I get to renovating the bed ;)

... oh, and the missing screw for mounting the heater house you mentioned - look at the picture from inside the cab looking into the A/C housing. On the right you'll notice it right there.
 

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