Gremlin AC ??

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   My 73 Gremlin is a factory AC, but much of the system was disconnected over the years. I'm getting ready to get it operating again and have a few questions. 

1. In the 73 TSM, there is a brown wire shown that connects to the AC clutch. It states that the wire is part of the main harness. However, I can't find it under my hood or on the harness routing diagram or the vehicle diagram. I'd like to know if the wire is for sure brown (I have a few unused wires taped back, none are brown) and where that wire exits the harness. I can't tell if it's supposed to be on the left or right side of the engine. 

2.  The TSM also mentions a vacuum controlled heater valve. Is that to be firewall mounted with one of the heater hoses running through?

3.  The TSM also mentions a vacuum AC door in the dash. Where does vacuum pass through the firewall to get there?

I'm sure I'll come up with more as I work, but these will get me started. Thanks!

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bad72amx Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Sep/10/2009 Location: Louisville, KY Status: Offline Points: 118	Post Options Post Reply Quote bad72amx Report Post Thanks(0) Quote Reply Topic: Gremlin AC ?? Posted: Jul/14/2016 at 5:31pm
	My 73 Gremlin is a factory AC, but much of the system was disconnected over the years. I'm getting ready to get it operating again and have a few questions. 1. In the 73 TSM, there is a brown wire shown that connects to the AC clutch. It states that the wire is part of the main harness. However, I can't find it under my hood or on the harness routing diagram or the vehicle diagram. I'd like to know if the wire is for sure brown (I have a few unused wires taped back, none are brown) and where that wire exits the harness. I can't tell if it's supposed to be on the left or right side of the engine. 2. The TSM also mentions a vacuum controlled heater valve. Is that to be firewall mounted with one of the heater hoses running through? 3. The TSM also mentions a vacuum AC door in the dash. Where does vacuum pass through the firewall to get there? I'm sure I'll come up with more as I work, but these will get me started. Thanks!
	Mine: 1972 Javelin AMX 1973 Gremlin X Levi's In the family: 1969 AMX 1969 Javelin SST 1982 SX/4 1977 Matador

Fluffy73 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Nov/21/2007 Location: Castlegar, BC Status: Offline Points: 3059	Post Options Post Reply Quote Fluffy73 Report Post Thanks(0) Quote Reply Posted: Jul/14/2016 at 6:27pm
	Chances are, much of your wiring has been cut off or removed. The brown wire that runs to the A/C clutch simply runs from the A/C thermostat on your dash control. If you remove the dash control, you'll find the brown wire there. The vacuum controlled heater valve on Gremlin/Hornet is an inline job that basically gets spliced into the hot side of the heater core hose. I believe what #3 refers to is the A/C vacuum switch on the blend door on the heater box itself. If you remove your package tray, it should be facing the passenger. What this switch does is when the blend door closes (you move the control to A/C-OFF) it closes off the outside air, and in doing so, triggers this vacuum switch which shuts off the heater control valve we mentioned earlier. The routing for this is easy. Connect one side of the switch to vacuum source, connect the other side to the heater valve. I believe heater valves are still available from certain sources but others could be used in a pinch. I know Dodge/Plymouth K-cars used a variation that connected to both hoses and allowed coolant to circulate but NOT pass the valve when in the A/C mode. These are also plastic so are immune to corrosion.
	I am genetically incapable of being Politically Correct.

Pdok Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Apr/03/2011 Location: Alabama Status: Offline Points: 1025	Post Options Post Reply Quote Pdok Report Post Thanks(0) Quote Reply Posted: Jul/14/2016 at 6:34pm
	FWIW Clutch wire is Light Blue on my '76 yours might be different of course...if you have the switch intact on the dash, you can check likely wires for 12V when it is on/ 0V when off to verify. The under dash vacuum line is very small diameter, routes through the same hole with the speedo cable, at least on mine. That little vac switch under the dash has a part number, can't recall right now, but you can "maybe" find it through partsvoice that way. Unlikely, though. I found it on eBay via part number, wasn't advertised as AMC! Also, they apparently tend to go bad inside and not hold vacuum. Edited by Pdok - Jul/14/2016 at 6:39pm
	76 Grem X 258/904,4.0 head/MPFI, Comp X250H cam, Hughes springs, Clifford header, serpentine swap.

bad72amx Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Sep/10/2009 Location: Louisville, KY Status: Offline Points: 118	Post Options Post Reply Quote bad72amx Report Post Thanks(0) Quote Reply Posted: Jul/14/2016 at 7:55pm
	Thanks for the replys. The wiring doesn't appear to have been cut up at all, and I'm not ready to pull the dash quite yet. The plan is to pull the entire interior to insulate everything after show season is over. The car is running and driving well, and the underdash AC parts are still there as far as I can tell. On the clutch wire, if I could just know whether it is or is not part of the harness, and where it is located in the engine bay that would help. For the heater valve, is that too located under the dash?
	Mine: 1972 Javelin AMX 1973 Gremlin X Levi's In the family: 1969 AMX 1969 Javelin SST 1982 SX/4 1977 Matador

Pdok Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Apr/03/2011 Location: Alabama Status: Offline Points: 1025	Post Options Post Reply Quote Pdok Report Post Thanks(0) Quote Reply Posted: Jul/15/2016 at 8:54am
	On mine it is on the passenger side of the harness and I think it was a separate wire from about where the solenoid wires split off. I might be wrong about the color it was pretty faded. It ran as a single wire to the clutch. Heater valve is in the engine compartment in-line with the hose to the core. The vacuum switch is under the dash.
	76 Grem X 258/904,4.0 head/MPFI, Comp X250H cam, Hughes springs, Clifford header, serpentine swap.

Traveller Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Feb/26/2011 Location: Idaho Status: Offline Points: 1011	Post Options Post Reply Quote Traveller Report Post Thanks(0) Quote Reply Posted: Jul/15/2016 at 4:44pm
	Oddly, the vacuum hoses run all the way from the passenger side on the heater box inside the car, to two holes over towards the steering column side, then to a vacuum nipple on the intake (source) and the vacuum controlled heater valve. Mine were in the loops attached to the firewall that hold the wiring harness. There were two small grommets where the hoses went through the firewall on our blue car. The non-A/C car does not have those holes.