Speedo stuck at 130 mph

[Purepony]

So I started the car to let any air from the cooling system out and I noticed my speedometer was going crazy. It went something like

0-25-55-70-130 and I turned stopped

I look under the car and it seems the speedometer cable was melted on the exhaust pipe. It was actually melted and stuck so after I turned the car off speedometer stayed on 130

Any ideas on what to look for ?

Will be ordering a new cable but has this happened to anyone ? I'm really not well informed on gauges so I'm thinking it might be something I can't do but i would at least like to have an idea of what to look for or what could have happened

Thanks in advanced

[floorit426]

I'm wondering that maybe your needle may have broken, or bent? I had my cable melt against the exhaust, but the needle settled at 0. I replaced it and all turned backed to normal.

[tparker]

This seems weird to me. I believe my Speedo for my 70 challenger is mechanical. There is a "wire" that is inside the cable that rotates from a gear in the tranny. Not sure how melting would cause the speedo to move or stay pegged. Unless I am missing something fundamental. To be fair I am not sure how it works. lol.

Have you tried to disconnect the cable from behind the gauge? I think you can fairly easily reach up and un screw it other than a little arm contortion.

[jimynick]

The "wire" that you see inside the outer cable housing is actually a square formed wire wrapped cable and my guess regarding the other speedo being stuck at 130, is that as the outer housing melted and began to deform due to the heat, it likely grabbed at the hot spot and then had enough integrity to break loose and using the wound up energy in itself, accelerate so hard for only a moment, that it redlined the speedo and jammed it up at it's peak. It may have sheared off the receptacle in the speedo head, or as mentioned, torn loose from the needle. I'd pull the speedo head a ascertain which, were it mine. Either way, a genuine PITA that nobody needs. Good wake-up call though and I'll try to remember to check my old heap for that issue. 

[Purepony]

Damn so I'm guessing that removing the cable won't do anything ?
How hard is it to remove the speedo on a rally's gauge

[71vert340]

On my rally gage cluster when I had to remove the speedometer for repair. I removed the cluster from the dash. I lowered the steering column, disconnected all wiring, labeling all connections as I went. Disconnect speedometer cable. I also removed the radio for easier access. Remove anything else as needed. Good luck with everything. Take your time and be patient. As I've gotten older, I've found it easier to remove the seat to access stuff under the dash.
Terry W.

[floorit426]

As suggested, I'd first just reach under the dash and unclip the cable, to see if that makes a difference. Hopefully, it does and you only need to replace the cable. I replaced mine, last week. It took less than an hour.

[jimynick]

"As suggested, I'd first just reach under the dash and unclip the cable, to see if that makes a difference" By all means! Why make it more difficult than it requires?
  In case you didn't know, there is a plastic "finger?" that you need to squeeze to get the cable off the speedo head. If you drop the column and remove all the screws that go in at the base of the W/S, you should be able to loosen the dash side bolts and roll the whole dash towards you and you can get at the speedo easier.  A piece of thick wire will aid to control the rolling of the dash. When done, lift the dash back up, replace the screws and tighten the side bolts and have a nice cold beer!