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Old Aug 19, 2020 | 10:15 AM
  #1  
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Default 1968 Speedo

Hi, I recently had my drivers side instrument panel out , i did everything i needed to do , reinstalled it and everything was working correctly except i noticed the speedo wasn't working after i took it out . i figured ok thats an easy fix , just loosen everything back up and and reinstall the cable , which i am trying to do now but its like i can't get it to fit , is there a trick ?, i can get the end of the cable into the back of the speedo but i can't screw the attachment onto the back of the speedo , its like it wont reach , or wont go in ?
what am i doing wrong ?

Thanks

Dale
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Old Aug 19, 2020 | 11:29 AM
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My guess is the speedo drive cable is not fully seated in the speedo head.
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Old Aug 19, 2020 | 12:31 PM
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Thanks for the reply, i think you are right , however i am an idiot and got frustrated and took my wire cutters and snipped the end of the cable that goes into the speedo off a little bit to try and make it so i could screw it in , it didn't work , so i played with it a bit more and finally the cable seated properly , so then i screwed it into the speedo and it still doesnt work , so i am thinking that i screwed the cable up when i cut a little bit off the end , do you think that would be the case ?
I ordered a new cable
Now my Tach doesnt work , worked fine this morning , its screwed in and wasn't touched , maybe i pulled it out a bit when i pulled the dash out a bit ... man these cars are so hard and frustrating to work on.

Thanks
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Old Aug 19, 2020 | 12:35 PM
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If the cable is sticking out of the sheath try disconnecting the other end at the trannny, maybe the cable isn’t in the the tranny fully. If you can, try and spin the cable with your fingers and push it back into the sheath.
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Old Aug 19, 2020 | 02:05 PM
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You need to buy a new cable. Shortening it was NOT the thing to do. Removing the other end from the trans and turning the cable while trying to insert/seat the cable into the speedo socket is how you get that done correctly. Are you fully depressing the locking clip BEFORE (and while) you insert the cable in the speedo? You should only release that clip once the cable has fully seated into the socket.

Last edited by 7T1vette; Aug 19, 2020 at 02:06 PM.
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Old Aug 19, 2020 | 02:09 PM
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Originally Posted by 7T1vette
You need to buy a new cable. Shortening it was NOT the thing to do. Removing the other end from the trans and turning the cable while trying to insert/seat the cable into the speedo socket is how you get that done correctly. Are you fully depressing the locking clip BEFORE (and while) you insert the cable in the speedo? You should only release that clip once the cable has fully seated into the socket.
again no. The 68 cable has a threaded cap on both ends. Do not buy a new one. Hopefully you didn’t cut it too short. If it worked before then it would still work. Cutting it was a bad idea unfortunately

Last edited by Rescue Rogers; Aug 19, 2020 at 02:12 PM.
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Old Aug 20, 2020 | 07:54 PM
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I did buy a new one , just waiting for it to arrive , I think i cut it too short , just frustrated , oh well hopefully the new one will work , I got the tach to work , all the lights work , everything is good , just the speedo , so will report back once i get it .. and yes the 68 has a threaded cap on both ends , i shouldn't have cut it , stupid move.. i just couldn't get it to seat correctly , Now I know ..LOL

Thanks
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Old Aug 20, 2020 | 07:57 PM
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Good luck, let us know how it goes
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Old Aug 21, 2020 | 12:25 AM
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All GM speedo cables of that vintage have screw-on end pieces...on the SHEATH. The man cut the CABLE too short....
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Old Aug 26, 2020 | 06:26 PM
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Cable finally came in and ten minutes later we have a working speedo... awesome ..Thanks

I also took the opportunity to replace the drivers side door jam light switch , however i noticed that if i connect the two wires to it and screw it in all the way , my indicators ( right and left ) don't work and the courtesy light stays on even when the door is shut , if i unscrew it a bit the indicators work and the light shuts off when the door is closed , what is that all about ?

Ground ??

Thanks again

Dale
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Old Aug 26, 2020 | 07:37 PM
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You are correct, the switch may not have had a good ground. THe switch itself just connects the white wires to ground so the without the ground the electricity found it ground through the dash lights.
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Old Aug 27, 2020 | 11:05 AM
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Thanks , Thats what I thought .. I'll check the ground

appreciate the help

Regards
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