wtb ac wiring
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Alat,
Not sure those are AC relays. I had one, of these on my '74, not connected to anything. I had an operating AC system before I rebuilt it this summer. It certainly wasn't associated with that AC system. I think the one I had may have been associated with the emissions system. I've removed it from the car.
Not sure those are AC relays. I had one, of these on my '74, not connected to anything. I had an operating AC system before I rebuilt it this summer. It certainly wasn't associated with that AC system. I think the one I had may have been associated with the emissions system. I've removed it from the car.
Those are emission speed relays, they are wired to the 2 valves with vacuum tubes connected to them up on the passenger side firewall. One went to the throttle linkage dashpot, the other maybe distributor.
Besides the speed relays 74s have a temp sensor in the radiator and a similar box to turn on condenser fan when temp gets too hot.
is there a connector there of just wires
so i just need the one relay for the fan right
so i just need the one relay for the fan right
Alan,
My relay for the cooling fan (turns on with AC) is beside the battery (the front one of two that are there).
My relay for the cooling fan (turns on with AC) is beside the battery (the front one of two that are there).
Alan - this is a wiring diagram for my car:
My car is from 1972, so there will be some differences, but there are two relays on this diagram. Part number 5 is a relay located on top of the wiring connectors just under my fuse block. This relay shuts off the heater fan whenever the a/c is switched on. The only relay under the hood in my system is number 9. It is an aluminum can relay located below the ignition coil on the inner fender. This relay is separately powered, with a flying fuse (number 7) not incorporated into the fuse block.
Both of these relays are activated by the fan switch (number 10). Relay 5 operates whenever the a/c fan switch 10 is on. The fan switch 10 also provides power for relay 9 (and for the compressor clutch at 12), but the temperature switch 11 controls whether power actually gets there. Switch 11 cycles both the compressor 12 and the nose fan 13 on and off depending on the temperature setting and the temperature in the car.
I did not have the temp sensor/relay in my car to enable the auxiliary fan 13, but have added the radiator switch and a relay to turn on my fan separately whenever coolant temp hits 81 degrees Celsius.
My car is from 1972, so there will be some differences, but there are two relays on this diagram. Part number 5 is a relay located on top of the wiring connectors just under my fuse block. This relay shuts off the heater fan whenever the a/c is switched on. The only relay under the hood in my system is number 9. It is an aluminum can relay located below the ignition coil on the inner fender. This relay is separately powered, with a flying fuse (number 7) not incorporated into the fuse block.
Both of these relays are activated by the fan switch (number 10). Relay 5 operates whenever the a/c fan switch 10 is on. The fan switch 10 also provides power for relay 9 (and for the compressor clutch at 12), but the temperature switch 11 controls whether power actually gets there. Switch 11 cycles both the compressor 12 and the nose fan 13 on and off depending on the temperature setting and the temperature in the car.
I did not have the temp sensor/relay in my car to enable the auxiliary fan 13, but have added the radiator switch and a relay to turn on my fan separately whenever coolant temp hits 81 degrees Celsius.
so is there a plug someone has for the relay as i dont have mine
I have a '74, with AC disconnected by the PO with a vengeance, apparently (lots of electrical things cut, disconnected, or missing.) I'm trying to locate relay #5 (the heater fan cut-out), at least where it is supposed to be. Nothing near the fuse block per Ohmess' explanation (I have the same diagram, but it is dated 1970. )Anyone know where relay #5 should be?
Sorry...didn't realize I was in Parts....
Sorry...didn't realize I was in Parts....
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It must be near steering column or fuse block as it is not in engine bay.