need speedo help

[TAZ 76]

Speedo hasn't worked since I got the car. Started checking things today. Pulled upper cable out, still one piece. Lower cable still one piece. Turned upper cable by hand, speedo works. Turned transducer by hand with one of the cables, the other side turns. Jacked rear of car up, with the lower cable only connected to the tranny, put in gear and the other end of the tranny cable dosen't move at all. What else could be the problem?
Thanks, Aaron

 

[WONKABOY]

SPEEDO FIX

Speedo hasn't worked since I got the car. Started checking things today. Pulled upper cable out, still one piece. Lower cable still one piece. Turned upper cable by hand, speedo works. Turned transducer by hand with one of the cables, the other side turns. Jacked rear of car up, with the lower cable only connected to the tranny, put in gear and the other end of the tranny cable dosen't move at all. What else could be the problem?
Thanks, Aaron

I JUST HAD MINE FIXED THIS PAST WEEK , FIRST THE LOWER TO THE TRANSDUCER , WORKED LOUSY WAS PINGING NOT A STEADY CLIMB , BROUGHT IT BACK AND TOLD THE MECHANIC TO BYPASSED THE TRANSDUCER WORKS EXCELLENT , I HAVE HEARD THAT THE TRANSDUCER IS ALWAYS THE PROBLEM AND EVEN IF REPLACE THEY ALWAYS HAVE TROUBLE WITH THE SPEEDO , BUY A CABLE FOR A NON CRUISE CONTROL 1981 , I RATHER LIVE WITHOUT CRUISE CONTROL THAN SEE MY SPEEDO FLUCTUATING UP AND DOWN!! OH IF THE BOTTOM CABLE DID NOT TURN WHILE JACKED UP A FRIEND OF MINE SAID THERE IS A NYLON BEARING TYPE IN THE TRANNY AND THEY ALSO WEAR OUT, MINE WAS NOT THE CASE , TRIAL AND ERROR I GUESS

HOPE THIS HELPS!!

 

[TAZ 76]

With mine the transducer seems to work, if not I have two others to try. How hard is it to check/change the nylon gear?
Thanks, Aaron

 

[cheeseral]

It's not hard to check the gear but have a pan ready when you pull it out cause you'll probably get some fluid when you take it out and that's probably where your problem lies. If the gear has been chewed up I'd drain your tranny and replace it. The driven gear will come out with the whole metal bullet that the cable attaches to, just remove the screw and tab holding it in and pull it out.

 

[Tom Bryant]

If you need to replace the gear remember that they are color coded by tooth count. Your gear will be discolored from age but be sure to get the same tooth count. Sometimes the gears seize up in the adapter sleeve that holds them in and the nylon teeth strip off easily. I'm not sure what the recommended lube is for the gear shaft when it's reinstalled. I'd probably use Lubriplate or other white lithium grease.

Tom

 

[TAZ 76]

Thanks for the replies, just got done with a show today so I will pull the gear out probably on sunday. Will post what I find.

Also can I put an MSD ign. on my 81 with the computer still in? If so is it worth doing? I was told it makes a noticable difference on starting and throttle responce.

Thanks, Aaron

 

[TAZ 76]

Finally got to put it up on stands tonite, found the driven gear wasted. The drive gear also has moved towards the rear of the tranny (not directly over the hole for speedo anymore). Will order new driven gear, retainer for drive gear, and some seals. Is pulling the tail section off for this a fairly idiot proof, or is there some tech things I should know?
Thanks, Aaron