78 Cordoba a/c questions
- Thread starter greenman692003
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Well, I would start with that left front fender....
How about a picture under the hood? Are all the A/C parts present? Is it not working because the freon is gone, or the belt is missing, the magnetic clutch won't engage... Let us know a bit more about the actual problem and we'll try to help out.
-=Photon440=-
How about a picture under the hood? Are all the A/C parts present? Is it not working because the freon is gone, or the belt is missing, the magnetic clutch won't engage... Let us know a bit more about the actual problem and we'll try to help out.
-=Photon440=-
greenman692003
Member
78 cordoba
I rather worry about the a/c first than the fender....All components are intact..except these two wire one on the compressor and a loose wire at the alternator see pic's....the compressor is getting no power, hoses and all else look to be ok
I rather worry about the a/c first than the fender....All components are intact..except these two wire one on the compressor and a loose wire at the alternator see pic's....the compressor is getting no power, hoses and all else look to be ok
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egrand1508
Well-Known Member
You've got a few things you have to get figured out first. To begin with, you need to make sure the compressor isn't seized. Loosen the belts a little and put a ratchet on the center bolt. It should have some resistance but still turn. If so, good!
Next, the wire in the top picture is the compressor clutch wire. Without that hooked up the clutch will never engage under the pulley to run the compressor. It is connected in series to the low pressure cut off switch at the receiver/drier canister above the right front fender. If you can't find a matching connector, it probably got cut off. Try tracing the wiring harness to see if you can find the point where it was cut. Otherwise, you'll have to run a new wire and splice it into one side of the switch. The other wire on the switch connects directly to the push button switches on the dash.
When you've got all that wired up you can try to see if the compressor will run. With the engine running, try pushing one of the a/c buttons to see if the compressor kicks in. Most likely it won't. In fact, it would be very surprising if it did work. Chances are the refrigerant is low or gone from the system. An a/c system that old is bound to have leaks, probably several, and will require repairs. Without refrigerant, there is no pressure and the switch at the canister will stay off. Also, the oil for the compressor is carried by the refigerant and without it the compressor will seize in no time. The switch really is there to protect the compressor.
Try jumping the low pressure cut off switch. Pull off the rubber boot with the two wires in it and stick a jumper wire between the connectors. If the compressor starts running, you know you got the wiring right, so the pressure must be low in the system. Warning: only run the compressor for a few seconds at a time...it doesn't have oil going to it, remember!
If it still won't run, re-check the wiring. You can try to run a jumper wire from the connector at the compressor that is in your top picture to the positve side of the battery. If it runs, you have a problem in the rest of the wiring. Remember, only run it a few seconds at a time! But, if it still won't run, you've got a bad clutch coil and it will have to be replaced.
If the refrigerant is low, then you have to make some choices. Either have a mechanic repair it, or try it yourself. You also need to decide if you want to use R12 or R134a or some blend of R134a. Don't think you can just go to Walmart and get a can or two of whatever they have and put it in. First, you said a kid had the car and heaven knows what he might have put in it and it might not be compatable. Also, the old oils and seals used in R12 systems won't work with R134a. And, if it has a leak, anything you put in will leak out too and you're just throwing good money after bad.
If you do it yourself with some work you can convert to R134a. But, you will need to buy, rent, borrow, or steal the following tools: an a/c manifold gauge set, a vacuum pump, a refrigerant can valve, fitting adaptors, and valve core tool.
The best thing to do right now is see if you get the compressor running and come back and discuss what is the best next step.
Next, the wire in the top picture is the compressor clutch wire. Without that hooked up the clutch will never engage under the pulley to run the compressor. It is connected in series to the low pressure cut off switch at the receiver/drier canister above the right front fender. If you can't find a matching connector, it probably got cut off. Try tracing the wiring harness to see if you can find the point where it was cut. Otherwise, you'll have to run a new wire and splice it into one side of the switch. The other wire on the switch connects directly to the push button switches on the dash.
When you've got all that wired up you can try to see if the compressor will run. With the engine running, try pushing one of the a/c buttons to see if the compressor kicks in. Most likely it won't. In fact, it would be very surprising if it did work. Chances are the refrigerant is low or gone from the system. An a/c system that old is bound to have leaks, probably several, and will require repairs. Without refrigerant, there is no pressure and the switch at the canister will stay off. Also, the oil for the compressor is carried by the refigerant and without it the compressor will seize in no time. The switch really is there to protect the compressor.
Try jumping the low pressure cut off switch. Pull off the rubber boot with the two wires in it and stick a jumper wire between the connectors. If the compressor starts running, you know you got the wiring right, so the pressure must be low in the system. Warning: only run the compressor for a few seconds at a time...it doesn't have oil going to it, remember!
If it still won't run, re-check the wiring. You can try to run a jumper wire from the connector at the compressor that is in your top picture to the positve side of the battery. If it runs, you have a problem in the rest of the wiring. Remember, only run it a few seconds at a time! But, if it still won't run, you've got a bad clutch coil and it will have to be replaced.
If the refrigerant is low, then you have to make some choices. Either have a mechanic repair it, or try it yourself. You also need to decide if you want to use R12 or R134a or some blend of R134a. Don't think you can just go to Walmart and get a can or two of whatever they have and put it in. First, you said a kid had the car and heaven knows what he might have put in it and it might not be compatable. Also, the old oils and seals used in R12 systems won't work with R134a. And, if it has a leak, anything you put in will leak out too and you're just throwing good money after bad.
If you do it yourself with some work you can convert to R134a. But, you will need to buy, rent, borrow, or steal the following tools: an a/c manifold gauge set, a vacuum pump, a refrigerant can valve, fitting adaptors, and valve core tool.
The best thing to do right now is see if you get the compressor running and come back and discuss what is the best next step.
greenman692003
Member
78 cordoba
After looking at the wiring diagram you had sent and googled about the low pressure switch and a light bulb went off...I now understand how the system works and will try jumping it to see if the clutch kicks on this weekend. The compressor has the newer ports to add the freon. But I don't know what else they have done...Getting the clutch to engage is a start.. I did depress the ac valve and there was no hissing its empty...
Will let you know.
Thanks!
After looking at the wiring diagram you had sent and googled about the low pressure switch and a light bulb went off...I now understand how the system works and will try jumping it to see if the clutch kicks on this weekend. The compressor has the newer ports to add the freon. But I don't know what else they have done...Getting the clutch to engage is a start.. I did depress the ac valve and there was no hissing its empty...
Will let you know.
Thanks!
greenman692003
Member
mopar 3488995 courtesy lens have been discontinued!!!!
egrand1508
Well-Known Member
If it's totally empty it has a leak and that will eventually have to be found and fixed too.
Also, check the fuse to make sure it isn't blown.
I found the light lenses on ebay here:
http://www.ebay.com/itm/1975-1976-1977-1978-1979-Cordoba-300-Charger-COURTESY-LENS-Magnum-/400254337870?pt=Motors_Car_Truck_Parts_Accessories&hash=item5d3104834e&vxp=mtr
They are more expensive, but I guess that's the only choice now. I knew I should have ordered an extra set for mine when I had the chance!
Also, check the fuse to make sure it isn't blown.
I found the light lenses on ebay here:
http://www.ebay.com/itm/1975-1976-1977-1978-1979-Cordoba-300-Charger-COURTESY-LENS-Magnum-/400254337870?pt=Motors_Car_Truck_Parts_Accessories&hash=item5d3104834e&vxp=mtr
They are more expensive, but I guess that's the only choice now. I knew I should have ordered an extra set for mine when I had the chance!
greenman692003
Member
78 Cordoba
I found those on Ebay too...the fuse that runs the ac also runs other accessory's I will start with the clutch....and go from there..
Thanks!
I found those on Ebay too...the fuse that runs the ac also runs other accessory's I will start with the clutch....and go from there..
Thanks!
greenman692003
Member
Hooked up the compressor wire and took a jumper wire to the low pressure switch and the clutch engaged with the motor running...and made no sounds....will check more this weekend...got the lenses off ebay, ordered a repro console lid...will call pick a part for the fender tomorrow....
Thanks!
Thanks!
furyfrank
Well-Known Member
I go to the local pull yourself yards and find alot of them cheap, they where used in alot of mopars.
furyfrank
Well-Known Member
Also if going by the pictures it has been coverted to R-134.
egrand1508
Well-Known Member
Looks like that blue cap is a 134 fitting somebody put on. Bad news is that it looks like it is still the old receiver/drier can on there and the 134 will turn those pellets inside to mush and carry it around the system. Also, they probably didn't change the oil and 134 won't pick up the old R12 oil and deliver it to the compressor.
It looks like at a minimum you will need to flush the system to get out as much old oil and gunk and put in new. You might also take off the oil pan on the compressor to clean that out too.
The best help you can get is from the service manuals. They do a really good job of explaining the system and the parts of it. Also, Mopar Muscle magazine did a series of articles on restoring Mopar a/c systems a couple of years ago and here are the links:
http://www.moparmusclemagazine.com/techarticles/34460_mopar_ac_system_restore/viewall.html
http://www.moparmusclemagazine.com/techarticles/34500_mopar_ac_system_restore_ii/viewall.html
http://www.moparmusclemagazine.com/techarticles/34597_mopar_ac_system_restore_iii/viewall.html
Keep in mind the articles are for restoring to stock look for a show car and as somewhat of a plug for Classic Auto Air. But, it does give a lot of good advice and shows you what is involved.
Good Luck.
egrand1508
Well-Known Member
Here is a video of an old Mopar Service Tech film from the 70's talking about the RV2 compressors. It might help explain some things too.
http://youtu.be/nD4o0gsiRUw
http://youtu.be/nD4o0gsiRUw
ArtH
Well-Known Member
"Customers have different ways of showing appreciation for a job well done."
Hmmm.
Did I hear him say discharge the old refrigerant into the air?
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