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speedometer problems

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Old Aug 14, 2005 | 12:11 AM
  #1  
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Default speedometer problems

Up until today my speedometer on my 79 has been working perfect. Today it died with no warning. Before I pull out the cluster and replace the cables ect. ect. ect.-----------is there something maybe simple I should be looking at first? Your input would be appreciated.
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Old Aug 14, 2005 | 12:13 AM
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Check the spedometer cable, and the cruise control unit, if you have cruise. Also, the plastic gear on the end of the speedo. cable in the transmission.
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Old Aug 14, 2005 | 02:10 AM
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This is how to check it on a 71 without cruise. Loosen cable from trans... give the inner drive cable a gentle but firm tug ... see if you can pull it out ... if you can it's probably broken ... because you should be able to pull it out ONLY from speedo end. If it don't come out with a tug, then chuck it up & spin it with a drill motor ... speedo should register ... if it don't then speedo has a problem ... OR ... maybe it's simply the cable has popped loose from back of speedo ... happens if someone has had a hand up in there fishing around. If you have cruise then it's abit more to it ... also check the gear in trans. I just lubed my 71's speedo & mech tach cables w/ moly lube ... my tach needle was jumpy ... disconnect outers at back of gages ... inner cables slide out the top ... aggravating, tight squeeze ... but now both gages smooth-as-silk.
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Old Aug 15, 2005 | 01:59 PM
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If the odometer still works, then you've got a bad speedo gauge. Hope you got deep pockets, they are outrageously $$$$.
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Old Aug 21, 2005 | 01:23 PM
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Default Speedometer problems

I too have a problem with my speedometer. It quit, as did the odometer. I know the cruise is shot and fallen apart, but can that stop the speedo? I checked the cables at the tranny and at the engine going into the dash, and they are connected, but I didnt' remove them so I guess something could be broken. Any ideas? I live in California and the closest speedometer repair place is 60 miles away.

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Old Aug 21, 2005 | 04:28 PM
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Sorry to Hi-jack this thread, but I have a similar problem. My speedometer works for only about one minute after I start rolling, then drops to zero. Does anyone know what could cause that?
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Old Aug 21, 2005 | 06:41 PM
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pull the cable from the trans and put a batter drill on it and have someone spin the drill, if the needle dont move (and you dont have cruise) its probably the cable i just changed mine last year ,pretty e/z
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Old Aug 21, 2005 | 06:43 PM
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so, what if I DO have cruise control? I'm pretty sure it doesn't work.
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Old Aug 21, 2005 | 09:51 PM
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the cable goes to a transducer, i would think that if the transducers bad you would have to bypass it, im guessing, i dont have cruse in a 73 and the car that i do doesnt have a speedo cable it has a generator on the trans that sends a/c current to the dash where there is a rectifier that converts it to d/c at the speedo,the faster the more the needle moves, someone who has that set up would have to chime in ..is there a way to take the cables off the transducer and go directly from the trans to the speedo by connecting the 2 - 1/2 cables toughter????
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Old Aug 21, 2005 | 10:09 PM
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you can take the transducer a part take out the spring that is bound up inside .make shure that the gears now turn freely .put it back together .your cruise will not work but your speedo will . matt 1980 check your cable ends,they could be rounded off .
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Old Aug 21, 2005 | 11:10 PM
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Same thing happened to me. Bought a rebuilt transducer put it all together and no speedo. Turnned out to be the cable from trans has a nylon end on it. It was sharpened like a pencil and would not turn transducer.Check cable on transducer end. Wish someone would post a picture of what cable end looks like. May be able to form one with JB Weld. until I get one ordered. TIA............
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Old Aug 22, 2005 | 09:45 PM
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Originally Posted by ChevyL82
Same thing happened to me. Bought a rebuilt transducer put it all together and no speedo. Turnned out to be the cable from trans has a nylon end on it. It was sharpened like a pencil and would not turn transducer.Check cable on transducer end. Wish someone would post a picture of what cable end looks like. May be able to form one with JB Weld. until I get one ordered. TIA............
looks like your wish came true,,just as your post rolled to page 2!!-----------this first photo is from my 73 no cruise control!! 2 piece cable,,this photo is the 1/2 that goes from the trans ----
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Old Aug 22, 2005 | 09:46 PM
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Originally Posted by ChevyL82
Same thing happened to me. Bought a rebuilt transducer put it all together and no speedo. Turnned out to be the cable from trans has a nylon end on it. It was sharpened like a pencil and would not turn transducer.Check cable on transducer end. Wish someone would post a picture of what cable end looks like. May be able to form one with JB Weld. until I get one ordered. TIA............
looks like your wish came true,,just as your post rolled to page 2!!-----------this first photo is from my 73 no cruise control!! 2 piece cable,,this photo is the 1/2 that goes from the trans -it has a steel end thatgoes into the trans-----------------------------
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Old Aug 22, 2005 | 09:51 PM
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this is the other 1/2 that goes from the end of the 1st ,,,1/2 to the back of the speedo-this end HAS THE PLASTIC END--THE PLASTIC END GOES INTO THE SPEEDO NOT THE TRANS------------
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Old Aug 23, 2005 | 11:24 PM
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Thanks for photo mine's shot Plastic piece on mine is flush with cable end.
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