'67 LeSabre: how to dismount radio?

Hi there,

would like to get my (supposedly original/factory) radio "Sonomatic AM" out of the dashboard of my 1967 LeSabre - the radio seems to be either out of order or not properly connected. No sound, just illumination of the dial as soon as I turn on the light.

So, do I approach this from the front (remove knobs, remove front plate/bezel, remove radio) or somehow rather from the backside? I already peeked from underneath but found no obvious screws etc.

Thanks for any insighs!

Cheers,
Harry20211213_100132.jpg
 
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Odds are your 55 year old center dash speaker gave out but you have to remove the radio to access it anyway. You will have to work in both directions to do this.

If you have AC remove the center duct from under the dash. Remove the ashtray and its bracket from the dash. Disconnect the plug from the unit and either look for or feel around for the Bracket at the rear of the radio. Either remove the screw from the bracket to the radio or unscrew the bracket from the dash whichever is easier for you.
Remove all 4 knobs. If you have a rear speaker pull out the fader unit and let it hang by the wire. Remove the 9/16 nut on each stem with a deep socket and work the radio out from under the dash. Be careful for wiring that may be under the unit holding it up. Don't just pull hard watch from under the dash as you remove the unit.

Important Note, if you get tired or get a cramp in your neck or shoulder walk away and go back later. If you're not familiar with this task it can be physically challenging for most.

ONLY 66 & 67 Buick full size car radios fit in that dash space because of the curve of the dash. You can have that am radio built into an am/fm CD mp3 satellite radio with Bluetooth. Do a search there are several companies that do it. Then you will have a nice original looking dash instead of one hacked up one like so many of these cars ended up looking like in the 70's and 80's.

ETA, there is the complete 1967 chassis manual in the reference section of this site. I strongly recommend that you bring it up and study this procedure before beginning. Visual aids are priceless.
 
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Hi oldfoneguy,

thanks for pointing me towards that great "chassis manual". I once more forgot that it contains everything instead of only "chassis related stuff" ;-)
So, it turns out my radio was only attached to the dashboard itself (by the two nuts around the knob stems) and missing any additional brackets etc. to its back.

What I found as well was apparently someone swapped the original single oval speaker with two separate round "Kenwood" speakers (4 ohm each):

20211214_104941.jpg

And here is the back of my radio, the black connector seen at the right bottom (with the 2 green wires going to the radio) was not connected to the car...just dangling around. Only the single male terminal on the right bottom corner of the radio was connected to a yellow wire, which seems to be correct according to the manual.

20211214_105010.jpg

The three terminals on the back of the radio (lower right) are labelled: GND / SPK / 12V.

So whats missing is just the connection to the speakers (both switched in serial to get 8 ohm) to GND and SPK.

Any idea what the unused left blue cable/terminal is for?

Fingers crossed...

Cheers,
Harry
 
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Ah-ha the hacks have been there already. Harry the ground for power originally came from the metal to metal contact between the radio and the dash ie the rear bracket that's missing. That ground in the plug is the audio ground. For power ground run a wire from the radio case to the dash somewhere. That blue wire would be for the optional rear speaker.
 
Ok, will have some quick/temporary wiring today to see if the radio is still working at all. After that I'll decide on how to proceed...

Btw...when digging inside the dashboard behind the radio I found some unused wires/connectors, do you by any chance know what they are supposed to connect to?

1. A single black connector with orange/black cable (the one I'm holding on photo)
2. A "3 terminals" black connector with black/orange/whitish cables (foreground)

20211215_094109.jpg

And another question: My cigarette lighter is not working. I checked the fusebox and there is an empty fuse slot marked as "cig. ltr." (right column, 2nd from top). But the fuse slot only has one terminal remaining, the right one seems to be missing. Are there replacements of the entire fusebox or do I have to fix this (maybe by switching the cigarette lighter fuse to another unused slot)?

20211215_094239.jpg

Thanks again!

Cheers,
Harry
 
Orange/black is usually a constantly hot lead. I noticed that you don't have a clock the single lead may be for that. My question to you would be what else in the car isn't working? The 3 wire plug looks like it may go to the blower motor but don't quote me on that. Let's go back to that chassis manual. There are excellent wiring charts in there. The dash wiring chart should be able to pinpoint those for you.

That fuse box is going to be a challenge. You can pull it off the wall and try to replace just that terminal. They are generally crimp on but could be soldered. I remember seeing them for sale a long time ago but not sure where. Could have been yearone.com or an old JC Whitney catalog. It may have been so long ago that style of fuse was still have been in use. I'm an older guy. Replacing the entire fuse box would be an inconceivable nightmare that I would never attempt. Remember these boxes aren't solid state. There are wires in the back with the connectors that hold the fuse poking through bakealite plastic. The box itself doesn't do more than hold those connectors, insulate them from ground and each other.
 
That fuse box needs replaced. The fuse terminals are rusty. But if you are not comfortable with that, you could remove the fuses and get in there with a die grinder and polish all the fuse terminals. As for the one cig lighter buy a good inline fuse holder and find a source of electricity that is hot all the time and hook it up. Sometimes you just can not repair something like you would like. But you can still do the next best so that it is safe.
 
@oldfoneguy:

Yes, orange/black seems to be indeed a constant 12V lead, same as the red wire of the 3 wire plug. And you were also right, the car came without a clock, so this might be for that option. I checked all electrical gizmos but all seem to work. So this 3 wire plug could be for another option, which is not present in my car.

I properly connected the radio but it won't do anything (except light the frequency scale) and afterwards discovered that one of the speakers is shot...

Is there a "modern" direct replacement for the oval factory speaker? Does someone know the speaker size?

@suntreemechanic:

Rust is only on the free ends of the fuse clamps/clips towards the seat - the rest of the fuse contacts seems to be ok. And everything electrical is working fine.


But I found out in the meantime why the cigarette lighter is not working - in fact its fuse and connection are both ok. The culprit seems to be some unknown cylindrical part sitting between the lighter terminal (the bottom threaded end, where the cable will be attached to) and the lighter jack itself (upper end, where the actual cigarette lighter part will be inserted from the front).

I've attached a picture of the part in question (looks like a drum of some sorts), which is supposed to be an electrical conductor, but isolates instead. Maybe some kind of additional (thermal) fuse?

20211216_114919.jpg

Cheers,
Harry
 
Well I've never seen that on a lighter receptacle before. I've seen the fiber board at the end of it with the terminal attached to that. Obviously that needs to be replaced to get the lighter working again. Looks it's some kind of fuse link. It probably died from age more than anything else.
Are you sure you had a good hot and ground to the unit? The radio could be shot. Let's face it no GM item was ever designed to last for 55 years.

Best bet do an eBay search for the speaker. It's a funky size not a 6x9. Don't remember exactly but maybe a 4x6? If you had the original speaker it could be re-coned and re-coiled. Possibly yearone.com may have it but they don't have a catalog for full size Buick but it may be equal to a chevy or Pontiac full size from the same year. You can also check with oldbuickparts.com, thepartsplaceinc.com and opgi.com. There's a very short list of suppliers for full size Buick parts compared to mid size cars.

The original speaker in the dash of my 67 Electra Convertible had been re-coned and re-coiled. Not by me though. It was a plastic cone with foam edge and a tweeter cone in the middle. It worked very well but how much do you need for AM?
 
Luckily, the solution for this "cigarette lighter drama" has been quite straightforward - I just had to unscrew that strange "mini drum" part from the lighter backside to reveal just another (identical) threaded terminal. So when I finally connected that to the matching "hot end" plug, the lighter works just fine.

And just for the fun of it here are the disassembled innards of that "mini drum":
20211217_103029.jpg

From left to right:
1. The "previous" threaded terminal poking through some cardboard isolator and ending in a weird cross shaped contact/spring thingy
2. A badly corroded, two part "contact plate" construction, held together by a "paper" sleeve (the part above them)
3. A badly corroroded and rather weary spring
4. The outer "drum" shell, with another contact poking through cardboard isolator and ending in a matching female thread to the lighter

Well, seen a lot so far in my life but this is a complete puzzle to me. I'd assume this could somehow limit the current the lighter draws - just by a set of spring-loaded contacts, so acting as some kind of reusable fuse. But in that case it could very well become really hot, which would be absolutely nonsense to being wrapped into a "paper" sleeve. Or its just a part that should fail early and keep the passengers from smoking too much ;)

My current plan for the radio: See if it actually works with a pair of working speakers and then decide from there.
But as it is just an AM radio with absolutely limited usage today I guess I'll just discard its innards and convert it into a bluetooth receiver/amplifier. I guess thats the easiest/cheapest way to give it some use/meaning.

Cheers,
Harry
 
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Harry I see your in Germany so is it possible that your car is European built? I believe Buick had or has a factory in Belgium that built cars for the European market. I've seen several Europe only features on offshore built American cars over the years so perhaps that fuse/breaker is yet another useless safety item. Like if a kid stuck their finger in the receptacle it would be only a momentary shock instead of continuously cooking like an American kid would. How did I ever survive to the age I am now without that?
 
Hmm, don't think so. My build sheet says "Kansas City plant" and the car has been imported from Canada over here 2-3 years ago.
 
From Canada ok. They have differences with the US as well. So if the car was built for their market it had to meet their safety requirements as well.
 
@oldfoneguy:

Yes, orange/black seems to be indeed a constant 12V lead, same as the red wire of the 3 wire plug. And you were also right, the car came without a clock, so this might be for that option. I checked all electrical gizmos but all seem to work. So this 3 wire plug could be for another option, which is not present in my car.

I properly connected the radio but it won't do anything (except light the frequency scale) and afterwards discovered that one of the speakers is shot...

Is there a "modern" direct replacement for the oval factory speaker? Does someone know the speaker size?

@suntreemechanic:

Rust is only on the free ends of the fuse clamps/clips towards the seat - the rest of the fuse contacts seems to be ok. And everything electrical is working fine.


But I found out in the meantime why the cigarette lighter is not working - in fact its fuse and connection are both ok. The culprit seems to be some unknown cylindrical part sitting between the lighter terminal (the bottom threaded end, where the cable will be attached to) and the lighter jack itself (upper end, where the actual cigarette lighter part will be inserted from the front).

I've attached a picture of the part in question (looks like a drum of some sorts), which is supposed to be an electrical conductor, but isolates instead. Maybe some kind of additional (thermal) fuse?

View attachment 13334

Cheers,
Harry
Hi Harry, I’ve had similar problems with the lighter in my ‘68 Wildcat, I found a similar lighter that worked & unscrewed the original knob & refitted it to the ‘new’ lighter, & that worked out good;
 
Luckily, the solution for this "cigarette lighter drama" has been quite straightforward - I just had to unscrew that strange "mini drum" part from the lighter backside to reveal just another (identical) threaded terminal. So when I finally connected that to the matching "hot end" plug, the lighter works just fine.

And just for the fun of it here are the disassembled innards of that "mini drum":
View attachment 13335

From left to right:
1. The "previous" threaded terminal poking through some cardboard isolator and ending in a weird cross shaped contact/spring thingy
2. A badly corroded, two part "contact plate" construction, held together by a "paper" sleeve (the part above them)
3. A badly corroroded and rather weary spring
4. The outer "drum" shell, with another contact poking through cardboard isolator and ending in a matching female thread to the lighter

Well, seen a lot so far in my life but this is a complete puzzle to me. I'd assume this could somehow limit the current the lighter draws - just by a set of spring-loaded contacts, so acting as some kind of reusable fuse. But in that case it could very well become really hot, which would be absolutely nonsense to being wrapped into a "paper" sleeve. Or its just a part that should fail early and keep the passengers from smoking too much ;)

My current plan for the radio: See if it actually works with a pair of working speakers and then decide from there.
But as it is just an AM radio with absolutely limited usage today I guess I'll just discard its innards and convert it into a bluetooth receiver/amplifier. I guess thats the easiest/cheapest way to give it some use/meaning.

Cheers,
Harry
Harry,
This part is the Cigar Lighter Fuse, GM part no 1350626 in group 9.712 as shown in the attached Buick Master Parts Book. It is a thermal fuse that protects the lighter element against overheating in case the knob is held down too long for example.


There is one listed on eBay:

 

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Hi oldfoneguy,

thanks for pointing me towards that great "chassis manual". I once more forgot that it contains everything instead of only "chassis related stuff" ;-)
So, it turns out my radio was only attached to the dashboard itself (by the two nuts around the knob stems) and missing any additional brackets etc. to its back.

What I found as well was apparently someone swapped the original single oval speaker with two separate round "Kenwood" speakers (4 ohm each):

View attachment 13330

And here is the back of my radio, the black connector seen at the right bottom (with the 2 green wires going to the radio) was not connected to the car...just dangling around. Only the single male terminal on the right bottom corner of the radio was connected to a yellow wire, which seems to be correct according to the manual.

View attachment 13331

The three terminals on the back of the radio (lower right) are labelled: GND / SPK / 12V.

So whats missing is just the connection to the speakers (both switched in serial to get 8 ohm) to GND and SPK.

Any idea what the unused left blue cable/terminal is for?

Fingers crossed...

Cheers,
Harry
Harry, the Delco Radio Service Manual for 1967 shows your car uses a model 7298924 radio. The speaker is a 4 x 10 inch with 10 ohm impedance, GM part no 7289354. Here is an old post on speakers from this site that gives some more information and a supplier that others have used:


Hopefully your radio has not been damaged by running it with the speaker(s) disconnected. These older Delco transistor radios were not meant to be operated without a speaker load on the power output transistor. The three-pin speaker/power connector at the lower right rear in your picture is designed as a safety interlock to prevent connecting 12V power to the radio without first plugging in the speaker. If the black and green wires are disconnected at the speaker, the interlock is defeated.

There should be a distinctive momentary thump heard from the speaker when the radio is first turned on. With luck the radio will still work. If you can get it to operate, one idea for upgrading to FM would be to install an external FM converter like they would have done in 1967. You would still be limited to 5 watt monaural output, no blue tooth etc. but this could be an economical way to retain the original AM radio and speaker. Here is a typical unit for sale on eBay:

 
@oldfoneguy:

Yes, orange/black seems to be indeed a constant 12V lead, same as the red wire of the 3 wire plug. And you were also right, the car came without a clock, so this might be for that option. I checked all electrical gizmos but all seem to work. So this 3 wire plug could be for another option, which is not present in my car.

I properly connected the radio but it won't do anything (except light the frequency scale) and afterwards discovered that one of the speakers is shot...

Is there a "modern" direct replacement for the oval factory speaker? Does someone know the speaker size?

@suntreemechanic:

Rust is only on the free ends of the fuse clamps/clips towards the seat - the rest of the fuse contacts seems to be ok. And everything electrical is working fine.


But I found out in the meantime why the cigarette lighter is not working - in fact its fuse and connection are both ok. The culprit seems to be some unknown cylindrical part sitting between the lighter terminal (the bottom threaded end, where the cable will be attached to) and the lighter jack itself (upper end, where the actual cigarette lighter part will be inserted from the front).

I've attached a picture of the part in question (looks like a drum of some sorts), which is supposed to be an electrical conductor, but isolates instead. Maybe some kind of additional (thermal) fuse?

View attachment 13334

Cheers,
Harry
Harry, page 120-90 in the Chassis Service Manual - Instrument Panel Connections seems to provide the answers on the loose connectors. The clock where used is fed by a single-pin connector having an orange w/black stripes wire. The power antenna switch if present is fed by a three-pin connector having black/ black w/orange stripes / white wires.
 
@Kiwijeff @TODD

Thanks heaps guys, this helped me a lot!

I just ordered some cheap 3,5" speakers to fix my "hifi" setup in the dashboard, to see if the radio is actually still ok (which I seriously doubt).

But I guess in the long run I'll convert the radio to fm/bluetooth anyway, by saving its outer shell/dials etc. and putting in a fm/bluetooth amplifier board. Will post further updates, when the speakers arrive - maybe its of use to someone here. ;)

Cheers,
Harry
 
So...found out in the meantime that the radio definately is shot. Even with the new speakers there was only a single "pop" sound when switching on, no static or even station signals.

As planned before I now removed all electronics, only left the volume knob (working as main switch) and the "station memory" mechanics, because thats fascinating to see. The single large lightbulb for the AM dials was replaced by two miniature bulbs with 1/10 current. The sound part is being provided by a $20 mini stereo bluetooth 50W module (bottom left corner, mounted using a piece of wood) obtained from Amazon (https://www.amazon.de/gp/product/B07YCK3LRT/).

For 12V and GND I reused the old terminals, so it remains "backwards compatible" here ;-)
But due to being stereo now and having separate SPK ground for both channels I had to attach the speakers using an additional 4 wire connector.

Although the sound is still rather thin (caused by the integrated micro amplifier of the bluetooth module and the tiny 3,5" speakers) its really cool to now being able to listen to Spotify or radio streams. Over that I can use it to hear Google Maps navigation.

20211231_145355.jpg

Cheers,
Harry

P.S.: The pictured speaker setup is only for testing, after finishing the radio conversion I installed them underneath the dashboard.
 
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Outstanding Harry. Never thought of converting a radio myself but if the situation should ever arise I have an idea of what to do. Saves hundreds as well. Happy New Year! Bill
 
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