I notice that the needle on the speedo on the 72 has the Wobblies. Cable has probably never been lubed, and I dug into it a little to try and get to it in the dash. My understanding is that the cable will pull out of sheath from the top side?

Pulled the clock out to take a peek. Started to take the speedo out and saw the auto trans prndl indicator start to move around. Since I don’t want that jewel destroyed, I thought it worth asking what is best procedure to get that cable out and lubed?

Here is where I am stalled at right now.

 

The best thing would be to just replace the cable. Chances are it may be frayed and no amount of lube will crrect that.

 

Reach into the clock opening and press the spring retainer around the cable end towards the speedo, and while holding the spring remove the cable sheath from the speedo. Once the sheath is removed the insert can be pulled out.

 

Follow what Kenneth stated. It looks like this...press in the tabs on both sides to release the tension which holds the cable secure to the housing...

 

All good advice ^^^
Adding, can disconnect at the transmission to flush out the casing. Lube the last 10" at the speedo head lightly to avoid having the grease get into the speedo.

 

Question: Disconnect from the speedometer and at the transmission and remove the cable from the sheathing? Re-insert the cable through the sheathing and lubricate per your post?

 

I think we're just using different terms or not necessarily on the same page?

So, maybe start again w/ terms we can agree on?

The entire "device" is most often called the "speedometer cable" and generally how you see it listed.

The most accurate is most likely the "cable" is the interior portion which actually rotates inside the dash speedometer unit and the transmission. The (interior) "cable" is independent from the exterior "sheathing" (sheath) or "tubing" (tube). Does that make sense?
Not speaking directly for Sugar Bear, but I believe what he is saying is to disconnect the entire "speedometer cable" (the sheath or the tube) from both the dash speedometer and the transmission. This then will reveal the entire "speedometer cable" i.e. the sheath/tube (exterior) and the cable (interior). The cable (speedometer cable) is the portion which rotates inside of the sheath/tube. You can then clean (flush) the inside of the sheath/tube (casing). I believe Sugar Bear is calling the casing the same as the sheath/tube. I've done this before on other cars - it's hit-or-miss. I do like Eric's suggestion. On car of this age, the entire "speedometer cable" is so inexpensive it's best to just replace the entire "speedometer cable". I hope what I said makes sense.

 

Does this help? Again, like Eric said - very often the interior (cable) becomes "frayed" and sometimes the interior lining of the casing/sheathing/tubing breaks down on these old speedometer cables and it's better to replace with a nice new cable.

 

I should point out in all of this. Yes, there actually was a point in time many years ago when you could actually buy the (interior) "cable" separate from the (exterior) sheath/tube/case. I doubt you can find the (interior) cable by itself any longer and for the price buy what it's commonly referred to as the entire "speedometer cable" for the car. It's late - tired of thinking any longer.

 

Yes cable inner part, casing/housing/sheath outer part. The outer part can be left in place and once the outer part is disconnected at the speedo the inner can be removed, cleaned and lubed. If the outer part is disconnected at the transmission but left in place it can be flushed.

Yes a new inner and outer part are inexpensive; but, I prefer to use serviceable OE parts due to quality concerns.

 

I attempted to flush my 1971 CS convertible OEM cable just like you suggested, because I had nothing more than a squeak going on which was dependent on speed of the car. I removed the cable from the dash speedometer and try as I might, there was no way the actual (interior) cable was able to be removed from the sheath - it was not going to happen unless I disconnected the cable from the transmission, as well. To be honest, the squeak was intermittent and varied by heat. On really hot days it would squeak, cooler/cold days it would not squeak. And, it wasn't terribly annoying. As you might guess - I learned to live w/ it because it was so infrequent. But, I have performed the exact same operation on other cars without an issue. Go figure.

 

Norm,

I agree with Eric. "The shortest way is the longest way." Replace the entire cable and sheathing with new. Unfortunately, I don't have a lift. I can only imagine the difficulty disconnecting the "assembly" from the transmission without a lift, and threading the assembly up through the car and connecting the "assembly" to the speedometer. I may buy 100ea 500MG Tylenol....LOL

 

It's honestly not that bad. Yeah, you'll have to navigate under the car. Jack stands make it far more comfortable (w/ or w/o a floor roller dolly). Only one place/hole where the speedo cable goes through the floor pan. There are a couple tie-off/clips but nothing excruciating. Removing the speedo assembly from the transmission is a snap. The entire speedo cable assembly itself is held onto the transmission by one bolt as I recall. I don't think you even have to remove the assembly. You unscrew the knurled nut from the assembly and the speedo cable comes off. I think you only need to remove the attachment bracket only if you change out the speedo gear (like if you had larger tires or were changing rear end gear ratios) so the speedo was calibrated correctly.

See if I can find a couple diagrams from the PIM.

 

 

Several good posts that were very helpful. A simple procedure really, but if you have never done it, a little difficult, mostly because ya just can’t see the connection very well on the back of the speedo. I used one of those flexible camera wand things and found the retainer clip that was just like VC said. I pushed it down like Fun71 said and the assembly pulled apart easily. I was able to pull the actual cable. It was very clean. No lube on it at all. No kinks, fresh, etc. looked really good. Lubed it with a chain and cable lube. Slid it back into the sheath easily, except for the last inch or so where I suspect the square cable was searching for its way into the transmission gear. Finally found its way OK. Reconnected the sheath to the Speedo with just a push on. Didn’t need to fiddle with the retaining clip.

So the process went well…

But the test drive reveals that the wobble is still there. So..I’ll probably buy a whole new speedo cable assembly and hope it goes away. I may get my nose down by the transmission first and see if there is an obvious problem?

 

Thanks for the report. Sounds like you did a good job w/o much to-do. Hopefully the resolve might be to install a new cable. It's doubtful it would be the speedo-driven gear in the transmission where the speedo cable attaches - although hey, anything is possible. And, to be honest it would be easier and less expensive if it was just the speedo-driven gear as opposed to the speedometer itself, in case a new speedo cable doesn't resolve the issue. Goo luck.

 

Oh yeah...regarding seeing the speedometer clip - you used a camera flexible cable wand. Try one of several hand-held, or technician/mechanic small mirrors on a stick. Use a flashlight & mirror you can visualize the backside of the entire dash cluster easily.

 

Yes VC. That is what I used. It did help. So simple when you totally understand it like several of you already do. Here is what I saw….


Speedo is on left, with retaining clip visible.

 

Oh yeah, I've been in there numerous times for a consortia of reasons. In the 2nd image I posted the PIM does a decent job of depicting the spring clip & how to remove the cable. Good work.

 

OLdGreenPaint,

Did you repair your speedometer? If you did, did you replace the entire cable assembly?

 

Yes Sir I did. I replaced the entire cable assembly with this one off of eBay.

https://www.ebay.com/itm/29509372024...mis&media=COPY

It was not too difficult to do. Hardest part was getting the high end, which is smallest end, pushed through the rubber boot on firewall. I removed two screws that hold the carpet in place behind the gas peddle. Got it out of the way. Then you can reach through the clock hole, grab cable end and pull it up to the back of speedometer and it slips right in place, and you cal feel the click when the retaining clip locks it in place. Bottom end is just a threaded collar that screws on to the transmission.

But…. I have not been able to test drive it yet. Fuel tank is on the ground while I get a new fuel sender here and installed. It may be an actual speedo gauge problem, and the cable may not be the solution. Won’t know until I can drive it some, which probably won’t be before middle of next week. I’ll post the results.

 

I had an incorrect reading speedo on my 72 over the past year.. I had already removed, cleaned and re-lubed the cable with no help. I eventually removed the speedo and cleaned and lightly oiled the mechanism. It spun much freer just by hand. You could feel the difference. What do you know, the speedo now reads correct.

 

What did you use to oil the mechanism? I guess a very light oil.

 

Got the tank replaced today. Took a short test drive. I would say that the speedometer wobbly needle is 90%+ better. Not totally perfect, but much better. I perhaps need to tune up the actual instrument also? (Per post 22)

 

Drove the car just yesterday. Wobble is now totally gone. New cable assembly seems to have burned itself in. Checking GPS speed to indicated speedometer speed shows speedometer is 5mph faster than GPS speed. So don’t know if it is a tire circumference issue, a speedometer calibration issue, or transmission speedometer gear issue. I’m going to get new wheels next year. Thinking 17” diameter. I may be able to fix this with tires?

 

Check the odometer for accuracy on an interstate highway with mile markers for at least ten miles. If both the odometer and the speedometer are off then you'll have to change the driven gear in the speedo adapter on the side of the transmission. If the odometer is accurate and only the speedometer is off then I'd say the speedometer head needs to be calibrated.

 

Thanks SB. Makes sense. May be a while before I get it back on the road to check it.