My speedo is sticking at a seemingly random spot between 20 and 60 mph.
I don't actually see if change, but it'll move from time to time.
Odometer is moving, trip odo is stuck.

Last year it was bouncing, so I removed it, had look inside, gears looked good, so I removed the speedo cable, cleaned it with brake cleaner and used dry graphite to lubricate it.
For the first 10 miles or so, it seemed to be working fine, then it went into it's current state.

One thing I do notice as odd is that when I press in the clutch about an inch, I can "feel" the speedo cable turning and the noise gets louder.

How can I fix this?

 

Speedo moved up yesterday on the drive home, then froze @ 70 mph

 

Originally it had the symptoms of a cable problem, where the speedo needle was still free and just responded to cable rotation (jerky as it was). You should have changed it when you had the chance. The cable damage causes the cable to 'whip' and send instantaneous bursts of "speed" into the speedometer. Apparently, that has now damaged the speedo so that the mechanism is sticking. You will likely have to remove the speedo and send it out for repair...or replace it...and you will still have to replace the cable and probably the sheathing, as well.

 

PIA, but remove the speedo from the dash, set at the dining room table with a clean surface and good lighting, use a mag glass if necessary, pull the needle off very carefully, straight up/off the stem, pull the card off via the 2 screws, and then you are down to the basic assy itself...

you need oil the back input bearing WD40 is fine, and then looking at the housing assy you find two large screws holding it together when you pull it apart, you have the pin from the rotating input assy that goes into the center of the spring loaded drum the pointer went on....

that center pivot needs cleaned with a Q tip and carb cleaner...then a dap of light silicone oil.....I got lazy and used WD40, been fine for years now....

 

Light oil (sewing machine type), silicone maybe; but WD-40 isn't a lubricant. Sounds like it helped on one, anyway. Maybe it just 'washed' some dirt off a spindle/pivot.

 

Mine hangs at 70 haven't gotten around to it yet.

 

I was under the car for a different reason today, took the speedo cable out of the transmission, hooked it up to a drill and it settled back to zero, sped up as the drill sped up.
No sticking, bouncing etc.
Put it back into the transmission and the speedo just stays at zero now.

I'm a bit perplexed now as to what the problem is, seems to be working fine for the end of the cable all the way to the speedo.

Thoughts?

 

When you push in the clutch your clutch linkage or lever is rubbing the speedo cable.
You probably have more than 1 problem. The speedo head is most likely worn out, once the shaft in the head picks up clearance its done ,sometimes lube will take up this clearance but its a bandaid fix. I believe the shaft in the head is a metal with lube built in,not sure what its called.
Down at the tranny if the fitting you screw the speedo cable on to is aluminum its probably worn out , go to the steel replacement fitting. Once the aluminum fitting wears it becomes wobbly and allows the little driven gear to move away from the internal drive gear and slips past wearing out the teeth.
Make sure on your speedo cable where it makes a sharp turn past the exhaust pipe that internally its not grabbing the cable and causing vibration.

 

It sounds like you have the speedometer cable in a bind, but in all reality the speedometer needs to be rebuilt!

There are only a few things that will bind the needle (spindle) up in a speedometer!

If the first worm bushing is wearing out in the speedometer head and you have the cable in the wrong position, it is possible for the cable to bind up the speed cup in the speedometer.

What happens is the extra clearance in the bushing can allow the first worm and magnet to push inward and bind! There is only about three thousandths clearance on the speed cup between the retainer and the first worm magnet. The speedo cable, if in a bind can push the clearance out of the speedo. An easy way to tell is to remove the cable from the back and see if the speedo stays at that speed. If you remove the cable and it falls then you know you have a problem in the speedo. Why? Just from the end play in the first worm being able to bind the speed cup.

You never want to put an lubrication on the speedometer internal bushing! The bushing is an oilite bronze bushing and this will increase the failure of the bushing. Combine that with the dust and dirt that can be attracted to this area and you'll eat the bushing out even faster. In sort term it may solve a squeak problem but over the long haul it will be a disaster.

In most cases, if you have a speedo failing you'll start off with a tinging noise coming from the speedometer! This noise is the magnet scraping the side of the speed cup. When this happens the needle will flutter and when it gets bad enough over time it will slam the needle usually breaking it.

Another indicator the speedometer has a major issue is your odometer not working. This happens from the misalignment of the first and second worm gear and is caused by clearance issues in the first worm bushing.

The speedo is a pita to remove from the car, and I hope you find something else causing the problem. If you do remove it from the car, I can rebuild it. The cost is 70.00 plus parts.. The end cost is usually around 130.00 +/-

Willcox

 

I did this picture a while back and posted it on the C1-2 forum, but maybe this will help some understand the internal components of the speedometer.

There is a misprint on this in calling all heads a W series. They are not and only 53-67 are W series heads. But the parts are still the same.

Willcox

18243

 

My odometer is working, my trip odometer is not.
The speedo has returned to picking a random speed and sticking.

I will change the cable, if that does not help, I'll be pulling it out and sending it in for repairs.

 

Just remembered something, on some cars if the speedo cable under the dash is in a bind like being pulled or pushed to 1 side it can cause the needle to stick BUT this is also because the head is worn out. On a car of my own I was able to position the cable so the needle wouldn't stick , lasted for a long time until the body fell off the frame.

 

the needle on my speedometer bounces while I drive. It shows the correct speed and doesn't stick, just bounces. what would cause this and how can I fix it?

 

Hmm, I'll have to try that.

 

Installed a new cable, speedo is working again.

It looks like it's around 7% off, based on a GPS. Wrong gear in the transmission?

 

Well, you got it fixed by the time I read this ...
... but for others w/ same symptoms ...

... take a close look at very tip-ends of cable core ... they should be rather well squared-off & measure about 0.104" ... cable tip-ends can & do become rounded-off & cause erratic speedo (& mech tach) reading.