78 Power antenna
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,458
Likes: 1
From: Collinsville MS
St. Jude Donor '08
78 Power antenna
I rebuilt my power antenna this weekend and put a new cable in it. I thought the thing was toast so I burglarized it and got it to working on the bench. Back in the car its a no go. I noticed on the bench I had to reverse the ground to get it go one way and reverse it again to go the another. The yellow wire in the car has been cut. I connected it to a power source and nothing. It has 3 wires, yellow, brown and green. I had read somewhere that these antennas would not work with aftermarket radios, but I figured I wouls play with it. Running it on an old supertuner for now. Any ideas?
Safety Car
Joined: Jun 2004
Posts: 4,380
Likes: 227
From: Beecher Illinois
Is the yellow wire that was cut the one that goes into the console and back to the relay? Is this a factory antenna? Factory wires are grey, white, and green at the antenna. And yes, you do connect the wires differently when bench testing. That's the function of the relay. Connect the wrong two wires and you'll smoke it.
To bench test it:
Green (+), Grey (-) to raise it
White (+), Green (-) to lower it.
Cross the grey and white = smoke!
If it's hooked up correctly, power applied to the yellow will raise it, remove power to yellow and it goes down.
The actual power to the antenna is an orange wire, always hot. That's how the antenna has power to retract when you turn the key off. Make sure you have that orange wire to the relay.
To bench test it:
Green (+), Grey (-) to raise it
White (+), Green (-) to lower it.
Cross the grey and white = smoke!
If it's hooked up correctly, power applied to the yellow will raise it, remove power to yellow and it goes down.
The actual power to the antenna is an orange wire, always hot. That's how the antenna has power to retract when you turn the key off. Make sure you have that orange wire to the relay.
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,458
Likes: 1
From: Collinsville MS
St. Jude Donor '08
I have the wire combos that I used on the bench wrote down in the shop but it seems the same as you described. But the one wire coming out of the antenna is definitely yellow. It turns gray inside the car. Color may be going due to old age or my eyes....
thanks, I will have to trace it back to the relay. There is an orange wire thats cut up there also. PO did a hack and slash job of a stereo installation.
thanks, I will have to trace it back to the relay. There is an orange wire thats cut up there also. PO did a hack and slash job of a stereo installation.
Melting Slicks
Joined: Oct 2006
Posts: 2,417
Likes: 336
From: Texas
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Safety Car
Joined: Jun 2004
Posts: 4,380
Likes: 227
From: Beecher Illinois
The aluminum housing power antenna is exclusive to 78s and early 79s. Other GM cars from the era also used it with different brackets.
If yours is clicking it's most likely the nylon leader is broken. This is the part that pushes the mast up and down.
All the vendors sell that repair part. Not actually correct for the 78 but it will work and look correct. You just gotta cut the hook off of it. About $30. GM PartsDirect has it for about $15. Of course add shipping.
GM/Delco part nos. are 22038195 or 22038197 with CB(about 4" longer).
There's a spring loaded pinch wheel inside the motor that can wear and cause slipping. I've taken a triangular file to recut the teeth and that's corrected the slipping problem.
If yours is clicking it's most likely the nylon leader is broken. This is the part that pushes the mast up and down.
All the vendors sell that repair part. Not actually correct for the 78 but it will work and look correct. You just gotta cut the hook off of it. About $30. GM PartsDirect has it for about $15. Of course add shipping.
GM/Delco part nos. are 22038195 or 22038197 with CB(about 4" longer).
There's a spring loaded pinch wheel inside the motor that can wear and cause slipping. I've taken a triangular file to recut the teeth and that's corrected the slipping problem.
Last edited by KapsSA; Jan 29, 2008 at 06:17 PM. Reason: part nos.
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,458
Likes: 1
From: Collinsville MS
St. Jude Donor '08
I bought the new cable for mine right here on the parts listing of the forum. I think it came from Zip. But it was in an AC Delco bag. My antenna didnt have a aluminum housing (no CB), it was black plastic and I had to drill the rivets out and then popped the keepers off the side. Cleaned it up, installed the new cable (too easy) and regreased. Put the keepers back on and stuck small nuts and bolts thru the places I had drilled the rivets out. Works like a charm on the bench. Now I just got to figure the damn relay out........
Safety Car
Joined: Jun 2004
Posts: 4,380
Likes: 227
From: Beecher Illinois
I bought the new cable for mine right here on the parts listing of the forum. I think it came from Zip. But it was in an AC Delco bag. My antenna didnt have a aluminum housing (no CB), it was black plastic and I had to drill the rivets out and then popped the keepers off the side. Cleaned it up, installed the new cable (too easy) and regreased. Put the keepers back on and stuck small nuts and bolts thru the places I had drilled the rivets out. Works like a charm on the bench. Now I just got to figure the damn relay out........
You can also get the repair part at any GM dealer parts counter. Price depends on the parts guy. Think list is about $35, I paid $22 for one. Gotta order it, tho. Took a day for mine to come in.
Burning Brakes
Joined: Nov 2004
Posts: 1,193
Likes: 176
From: Hillsborough NC
The aluminum housing power antenna is exclusive to 78s and early 79s. Other GM cars from the era also used it with different brackets.
If yours is clicking it's most likely the nylon leader is broken. This is the part that pushes the mast up and down.
All the vendors sell that repair part. Not actually correct for the 78 but it will work and look correct. You just gotta cut the hook off of it. About $30. GM PartsDirect has it for about $15. Of course add shipping.
GM/Delco part nos. are 22038195 or 22038197 with CB(about 4" longer).
There's a spring loaded pinch wheel inside the motor that can wear and cause slipping. I've taken a triangular file to recut the teeth and that's corrected the slipping problem.
If yours is clicking it's most likely the nylon leader is broken. This is the part that pushes the mast up and down.
All the vendors sell that repair part. Not actually correct for the 78 but it will work and look correct. You just gotta cut the hook off of it. About $30. GM PartsDirect has it for about $15. Of course add shipping.
GM/Delco part nos. are 22038195 or 22038197 with CB(about 4" longer).
There's a spring loaded pinch wheel inside the motor that can wear and cause slipping. I've taken a triangular file to recut the teeth and that's corrected the slipping problem.
Thanks
