OK, my son's 87 Cutlass has not had a working speedo since I gave it to him, I had good intentions... but... He got a ticket 44 in a 25! Now I am trying to fix it before court to try and help him out of his first ticket. Even though I could replace the cable myself, I paid to have it done, so I could get a receipt. The new cable did not fix the speedo. The technician said he thinks the speedo itself is what is bad. Any ideas? Anyone have a G-Body speedo?

 

Could be the cable, could be the speedo, could be a stripped plastic gear in the trans. I'd bet on the latter, since when the cable goes bad, it increases the friction and thus load on the plastic gear, causing the teeth to strip.

 

can you drive the speedo w a piece of the old cable and a drill ?

or can you drive the car and watch the speedo end of the new cable (not in the speedo) turn or not turn?

 

Did your 'parts changer' mention if the old cable was in fact broke?
Usually, a reciept for parts alone, will influence a judge.
Even a copy of a reciept will work. [and return the part!]
He should've known the difference from 25 to 44 though.

 

My "parts changer" told me the cable was really tight in the housing and felt that maybe it had damaged the speedo unit. The needle, will sometimes jump around, but will not even move other times. I had him replace the complete cable and housing assembly.

I sort of agree on the "should've known better", in his defense he has only been driving 3 months and it was a downhill speed trap.

I'll have to try the piece of cable in a drill test. But it will be next week before I get a chance.

 

Yeah - today's kids will bankrupt us all!
Heard that from about 5 guys with kids in the 15-25 yr. range!

 

I think maybe you need to find a mechanic who has a clue. The speedo cable is driven from the trans end and drives the speedo head. It is NOT physically possible for a binding cable to damage the speedo head - the only thing that would happen is that the added friction in the cable would impart LESS force than normal on the speedo head. On the other hand, you hopefully can see that a binding cable can clearly damage the plastic drive gears in the trans. Start by looking there. Yes, a jumping needle is a clear indicator of a binding cable.

 

I was out driving my 83 Hurst olds tonight, looked down and the speedometer and odometer had stopped working. Didn't hear anything, had the t tops off and Windows down. Any suggestions on Where to start look ing would be helpful.

 

Like Joe said earlier in the thread....start with the gears in the trans. The cable may need to be replaced as well.
You can test this theory out by disconnecting the cable from the transmission and connecting a drill to it and see if the speedometer registers. Check both directions if it doesn't register the first time. If that works then it's definitely the plastic gears in the trans.
I don't know what needs to be done to swap them out on the 200 4R trans so it might need to go to a trans shop to fix it.

 

Thanks for the advice svnt442, I'll give it a try.

 

The cables all work, the speedometer works by spinning the cable. Tried to turn the connection at the transmission, it felt like it was engaged. If it were broken wouldn't it be loose

 

Not necessarily.

 

If spinning the cable works the speedo, it has to be the gears in the trans.