TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > Body/Interior > HVAC
  New Posts New Posts RSS Feed - 73 Javelin heater connections
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

73 Javelin heater connections

 Post Reply Post Reply Page  123>
Author
Message
billd View Drop Down
Moderator Group
Moderator Group
Avatar
Forum Administrator

Joined: Jun/27/2007
Location: Iowa
Status: Offline
Points: 27751
Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Topic: 73 Javelin heater connections
    Posted: Apr/17/2018 at 7:10pm
I thought the PO had removed the right vent cable as I never saw one where it belonged - and today while digging to find how some things went together (properly, not how it was when I got it)
I found the cable and bracket tucked up inside the dash. The cable of course is snapped where it makes the transition to the smaller part of the housing from the thicker end part. I think I can repair that, though.........
My REAL question is more along the lines of the actual heater operation. 
I understand the 70 series controls the heater by mixing cold and hot air - want it hot inside, move the lever and it closes down the cold air in the mix. Want it cooler, move the lever and it allows more cool outside air into the mix.
Fine - but what about the heater valve?
Some of you may recall I asked about a proper heater valve for the car. Ross correctly indicated that AMC changed from the valve that screwed into the intake to the valve mounted in the hoses, so I bought that later style hose. 
I'm not ready to take the whole car apart and spend a month replacing the heater core yet but DO want to run proper hoses to the right places and go ahead and put the valve in place and make it "heater core ready".
I can't see how the heater valve was controlled - it's vacuum - but the car has no vacuum controls that I can find..
I went through every paragraph on every page in the "weather eye" part of the TSM - I even looked in the non-70 series areas for clues.
So it uses a vacuum controlled heater valve - fine, great - but what's it hooked to for vacuum??
The levers in the dash only have CABLES. 
Does anyone have a picture of the correct heater hose and valve arrangement, and info on what controls the heater valve?
I can't believe they'd even have a valve in there if there wasn't any means to turn it on and off -there's no vacuum going into the car at all, none, not a single hose. If there's no vacuum going into the car, and there's no hose coming out of the car for a heater valve, well - what the heck MORE is this car missing?
Geesh, hide the air vent cable and control, bypass the busted up heater core, no vacuum lines into the cabin none coming out, and the TSM shows NOTHING other than the air mix doors and cables!!
Back to Top
304-dude View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/29/2008
Location: Central Illinoi
Status: Offline
Points: 6126
Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Apr/17/2018 at 8:37pm
Been here with my 73... fortunately you found the passenger vent cable and lever. I had no clue as i thought nothing of it, since it was missing when purchased.

As for vacuum to actuate heater valve. There may be a plastic vacuum T where you get the vacuum line routed behind the vent control under the radio, for open and closed positions. The small vacuum line may go down behind the climate control on to a lever control ed vacuum switch... never had heater only but it may be an area to look for just to make sure,

Another area for AC cars, FYI... There is a small vacuum line to the vacuum can at the flap that uses a vacuum switch operated by climate controls, as all my cars had the mix vent for defogging wind screen.

Those are the only areas I can think of to look for any vacuum switches and controls for heater.
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
Back to Top
billd View Drop Down
Moderator Group
Moderator Group
Avatar
Forum Administrator

Joined: Jun/27/2007
Location: Iowa
Status: Offline
Points: 27751
Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Apr/17/2018 at 8:45pm
Like I said - no vacuum lines or hoses - not that I can find. 
So need to know what controlled the heater valve - where did the vacuum that goes to the valve come from - is there some sort of vacuum control somewhere in the car, where and what does it look like?
Non-AC cars are likely to be a bit different.
I also have a center section I bought that has the weather eye controls and there's nothing there at all that would or could go to anything to control vacuum - there are only two cables and those go to "doors" or similar - I think........
Back to Top
304-dude View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/29/2008
Location: Central Illinoi
Status: Offline
Points: 6126
Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Apr/17/2018 at 9:02pm
Originally posted by billd billd wrote:

Like I said - no vacuum lines or hoses - not that I can find. 
So need to know what controlled the heater valve - where did the vacuum that goes to the valve come from - is there some sort of vacuum control somewhere in the car, where and what does it look like?
Non-AC cars are likely to be a bit different.
I also have a center section I bought that has the weather eye controls and there's nothing there at all that would or could go to anything to control vacuum - there are only two cables and those go to "doors" or similar - I think........


SORRY, I thought when you mentioned 70 cars, you had an idea where some vacuum routing was to start and could not find where to go.

Not sure if the online vintage manual source given in your wiring thread, has heater and vacuum line info, its worth a shot.

Dltowers may have some good pictures for you as for his vacuum connections are on the firewall and his heater valve.



Edited by 304-dude - Apr/17/2018 at 9:05pm
71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
Back to Top
billd View Drop Down
Moderator Group
Moderator Group
Avatar
Forum Administrator

Joined: Jun/27/2007
Location: Iowa
Status: Offline
Points: 27751
Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Apr/17/2018 at 9:06pm
The vintage manual thread is hard to follow because of all the spaces (I can't believe people post things like that with SPACES in the names - browsers puke with it) but I did get a page to display and it's basically most of a TSM - and I have a 73 TSM and the heater section literally shows nothing.

So I need photos of where a heater valve is installed the hose routing, and where the heater valve CONTROL is that manages the vacuum. 
I can run vacuum lines - I need to know where the control is, what it is, what it looks like, etc.
Back to Top
JeeperJolene View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Feb/11/2018
Location: The Big Globe
Status: Offline
Points: 54
Post Options Post Options   Thanks (0) Thanks(0)   Quote JeeperJolene Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2018 at 12:39am
I'm going to have to deal with this soon as well on my 73. Right now,  the heater starts smoking out the dash if you try and turn it on, so either the fan is stuck or there is a nasty short. I peeked in the glove box and I'm not liking what I'm seeing. It's a complete mess.
Back to Top
pit crew View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Jul/08/2007
Location: NE Ohio
Status: Offline
Points: 4501
Post Options Post Options   Thanks (0) Thanks(0)   Quote pit crew Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2018 at 9:05am
Bill,

I have yet to disassemble a non-AC car but I can give you a rough idea of how they work. The heater control cable moves the blend door so you can control the temperature by mixing outside air with air passing over the core. Water is always flowing through the heater core until the heater control is placed in the OFF position.

Now the magic happens.

In the OFF position air is completely diverted around the heater core and where the control cable attaches to the blend door there is a small metal tab (RED note). That tab in the OFF position depresses a small vacuum switch mounted on the heater box roughly located behind the grab handle on the passenger side.

Manifold vacuum is supplied to that small switch and when the heater control is placed in the OFF position the switch is operated and routes vacuum back out the firewall to the control valve. The control valve operates and coolant flow to the heater core is cut off.

Again, my explanation is based on AC examples but it at least gives you a rough idea of how it works. I searched high and low but I can't come up with a picture of the vacuum switch mounted in the proper position. Sorry.



 


Edited by pit crew - Apr/18/2018 at 9:12am

73 Hornet - 401EFI - THM400 - Twin Grip 20
Back to Top
304-dude View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/29/2008
Location: Central Illinoi
Status: Offline
Points: 6126
Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2018 at 9:26am
The image of the vacuum switch is in perfect position to show how it mounts in regards to the box shown below.

The round metal disc plunger goes against the arm on the flap door, just below where the cable attaches to the door lever,

71 Javelin SST body
390 69 crank, 70 block & heads
NASCAR SB2 rods & pistons
78 Jeep TH400 w/ 2.76 Low
50/50 Ford-AMC Suspension
79 F150 rear & 8.8 axles
Ford Racing 3.25 gears & 9" /w Detroit locker
Back to Top
pit crew View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Jul/08/2007
Location: NE Ohio
Status: Offline
Points: 4501
Post Options Post Options   Thanks (0) Thanks(0)   Quote pit crew Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2018 at 9:43am
Oh, I should also mention that when mounting and adjusting that switch you want to position it so the tab is just touching it enough to operate the switch. Some people have mounted the switch hard against the tab and when the cable was operated the tab banged hard on the switch and broke it over time.

73 Hornet - 401EFI - THM400 - Twin Grip 20
Back to Top
73LevisX View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: May/23/2009
Location: Ottawa, ON
Status: Offline
Points: 181
Post Options Post Options   Thanks (0) Thanks(0)   Quote 73LevisX Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2018 at 11:13am
FWIW,
The vacuum line from that switch, on my '73 Hornet, exits the firewall near the accelerator cable and AC hoses and connects to the "nipple" on the metal vacuum can of the inline heater control valve pictured below. (The heater control valve is plumbed into the heater hose that exits the intake manifold.)


'73 Hornet X
304/904
Back to Top
 Post Reply Post Reply Page  123>
  Share Topic   

Forum Jump Forum Permissions View Drop Down



This page was generated in 0.063 seconds.
All content of this site Copyright © 2012 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or