66 Newport speedo

[Franklin Thomas]

Hello everyone
First time on this forum or any
My speedometer on my 66 Newport has locked up and broke the cable
Anyone have any experience with repairing one before I dive into it?
Is this a common problem?
Any insight would be appreciated
Thanks

 

[CBODY67]

Welcome! Nice looking convertible!

Did the speedometer head make any noises before things stopped?

Sometimes, the inner wear portion of the cable housing can degrade and let the cable touch the inner metal reinforcement of the cable, stopping things quickly. So pull the cable from the housing and inspect it FIRST! Might be that all you need is a new cable assy and related transmission gears.

CBODY67

 

[Omni]

Greetings from another buckeye

If you find the cable/casing is FUBAR give this business a try. http://imperialservices.net/ (may be wolverine but a great person to deal with.)
He made me cables when I added cruise control; to the '65 Newport.

 

[Franklin Thomas]

Thank you for your replies
I guess I should’ve been a little more detailed than what I have going on
The speedometer cable broke, and I bought a new one to replace it, and before I plugged it in to the transmission, I tried to turn the cable and it would not turn
I took part of the broken speedometer cable and stuck it in the back of this speedometer, and I could not turn it
So obviously, the speedometer itself is locked up
I’m going to remove the speedometer and take a look at it
I was wondering if anyone has disassembled one of these speedometer and what to watch out for when I do
I did find a couple instrument panels on eBay but I would like to fix the one that I have before spending the money on a used one that I have no idea the condition of
Any advice would be helpful

 

[CBODY67]

What the upper end of the cable plugs into is the "rear speed cup" of the speedometer. It is attached to the odometer mechanism by gears. So it runs the odometer mechanism directly. Inside that rear speed cup is the bar magnet which used magnetism to turn the "front spped cup" against a weak clockspring. The indicator needle is attached to the front speed cup by a small spindle. The clockspring returns the needle to or toward "0" as the speed decreases. The strength of the magnetism (which can be varied by a "zapper", at a speedometer shop) can vary the speed (stronger = faster, weaker = slower) to zeroin on the accuracy of the speed indicated.

The rear speed cup turns in a bushing, either plastic or bronze. Usually, when those bushings wear, the close alignment of the speed cups will get out of whack and cause noise. Either from the bushings or from the speed cups lightly touching. When the rear speed cup touches the front speed cup, it causes the needle to jump and/or peg to a higher speed. So that's why I inquired about "noises" or "needle activity".

On our '66 Newport, sometimes the needle would decrease a few mph, emit a light "snap", the needle jump a few mph, and then return to normal. As the odometer also suddenly increased to the next 10th/mile. Kind of like the odometer was getting stiff, tightened against the cable, then got enough force to "free-up" and things returned to normal. All within about a second or so.

Usually, the odometer drum is held in place by a clip on one end of its "axle". Then the trip odometer and main odometer are connected together. All of these things are "non-lubricated", but have little slack in them.

Like many automotive systems, no "rocket science", just that you need to know what you are looking at. Being careful and gentle in disassembly, looking for any wear situations in the process. Any lubes will need to be used sparingly and very low viscosity in nature (i.e., thin) lest a too-thick lube puts too much drag on things.

When the odometer on our '66 would snap/pop, I would use the trip odometer reset know to advance the trip odometer a bit to get it away from the possible "tight spot" as the individual drums rotated with each other. That normally fixed things for quite a while.

I've not been inside a '66 speedometer, but have seen others at the speedometer shop I used to take speedos for repair. Principles of operation are the same, just how things are constructed might and materials used might vary.

IF the speed cup bushings might need to be replaced, the speed needle is usually a slip-fit on the front speed cup's spindle. Holding the speed cup and gently twisting the center of the needle usually frees it on the spindle for careful removal. Reverse to install. Paying attention to the clockspring, too. Then ensuring the full-counteerclockwise orientation of there-assembled speed cup results in a "0" reading of the needle.

Hope this might help,
CBODY67

 

[Franklin Thomas]

What the upper end of the cable plugs into is the "rear speed cup" of the speedometer. It is attached to the odometer mechanism by gears. So it runs the odometer mechanism directly. Inside that rear speed cup is the bar magnet which used magnetism to turn the "front spped cup" against a weak clockspring. The indicator needle is attached to the front speed cup by a small spindle. The clockspring returns the needle to or toward "0" as the speed decreases. The strength of the magnetism (which can be varied by a "zapper", at a speedometer shop) can vary the speed (stronger = faster, weaker = slower) to zeroin on the accuracy of the speed indicated.

The rear speed cup turns in a bushing, either plastic or bronze. Usually, when those bushings wear, the close alignment of the speed cups will get out of whack and cause noise. Either from the bushings or from the speed cups lightly touching. When the rear speed cup touches the front speed cup, it causes the needle to jump and/or peg to a higher speed. So that's why I inquired about "noises" or "needle activity".

On our '66 Newport, sometimes the needle would decrease a few mph, emit a light "snap", the needle jump a few mph, and then return to normal. As the odometer also suddenly increased to the next 10th/mile. Kind of like the odometer was getting stiff, tightened against the cable, then got enough force to "free-up" and things returned to normal. All within about a second or so.

Usually, the odometer drum is held in place by a clip on one end of its "axle". Then the trip odometer and main odometer are connected together. All of these things are "non-lubricated", but have little slack in them.

Like many automotive systems, no "rocket science", just that you need to know what you are looking at. Being careful and gentle in disassembly, looking for any wear situations in the process. Any lubes will need to be used sparingly and very low viscosity in nature (i.e., thin) lest a too-thick lube puts too much drag on things.

When the odometer on our '66 would snap/pop, I would use the trip odometer reset know to advance the trip odometer a bit to get it away from the possible "tight spot" as the individual drums rotated with each other. That normally fixed things for quite a while.

I've not been inside a '66 speedometer, but have seen others at the speedometer shop I used to take speedos for repair. Principles of operation are the same, just how things are constructed might and materials used might vary.

IF the speed cup bushings might need to be replaced, the speed needle is usually a slip-fit on the front speed cup's spindle. Holding the speed cup and gently twisting the center of the needle usually frees it on the spindle for careful removal. Reverse to install. Paying attention to the clockspring, too. Then ensuring the full-counteerclockwise orientation of there-assembled speed cup results in a "0" reading of the needle.

Hope this might help,
CBODY67

Thank you for your reply
I guess I’ll jump down in there and take the instrument panel out
Can’t wait to get on my back under that Dash
Lol
I appreciate your insight
Funny, you said it’s not rocket science
Currently restoring an atlas rocket for the Air Force Museum in Dayton, Ohio
When I get this pedometer apart, I’ll post some pictures of the speedometer
Thanks again

 

[D Cluley]

I'd like to thank CBODY67 for saving me a lot of typing, because he covered a lot of what I was going to say.

I have a '65, but as far as I can tell the instrument clusters are the same.

The Factory Service Manual should have pretty detailed instructions on removing the cluster from the dash. It is not difficult, but it is fiddly. If you don't have the FSM, you can download it here.
Service Manuals – MyMopar

Two things to emphasize when pulling the cluster.
1. Disconnect the battery. You will be working with the 2 wires to the ammeter and don't want big sparks under the dash!
2. If you have a column shift, disconnect the link that goes to the indicator needle, or you will break that linkage.

Once the cluster is out, you remove the machine screws around the outside of the front and that releases the black and clear plastic cover. (don't miss the one down in the deep hole in the middle bottom)

The lower gauges are attached with more machine screws.

Now turn the cluster over and unscrew the 2 screws above and below where the speedometer cable goes. That will release the speedometer mechanism and its metal faceplate from the housing.

Once you are that far in, it shouldn't be too hard to figure out what's binding up. In my experience if one of the odometers jams up it will just chew up the plastic gears, but anything is possible.

You can chuck that short piece of cable in a power drill and run it in reverse to bench test things.

While you have it apart, this is a good time to clean and test all the light sockets and touch up the orange paint on the needles if needed. Definitely clean the connections for the ammeter. When I just did mine, I actually put double nuts on the studs holding the meter to the circuit board, and then 2 more nuts to hold each of the wires on. Any bad connection there leads to heat, and that's when your ammeter melts the dash.

 

[Franklin Thomas]

I'd like to thank CBODY67 for saving me a lot of typing, because he covered a lot of what I was going to say.

I have a '65, but as far as I can tell the instrument clusters are the same.

The Factory Service Manual should have pretty detailed instructions on removing the cluster from the dash. It is not difficult, but it is fiddly. If you don't have the FSM, you can download it here.
Service Manuals – MyMopar

Two things to emphasize when pulling the cluster.
1. Disconnect the battery. You will be working with the 2 wires to the ammeter and don't want big sparks under the dash!
2. If you have a column shift, disconnect the link that goes to the indicator needle, or you will break that linkage.

Once the cluster is out, you remove the machine screws around the outside of the front and that releases the black and clear plastic cover. (don't miss the one down in the deep hole in the middle bottom)
View attachment 605324

The lower gauges are attached with more machine screws.

View attachment 605325


Now turn the cluster over and unscrew the 2 screws above and below where the speedometer cable goes. That will release the speedometer mechanism and its metal faceplate from the housing.

View attachment 605326

View attachment 605327

Once you are that far in, it shouldn't be too hard to figure out what's binding up. In my experience if one of the odometers jams up it will just chew up the plastic gears, but anything is possible.

You can chuck that short piece of cable in a power drill and run it in reverse to bench test things.

While you have it apart, this is a good time to clean and test all the light sockets and touch up the orange paint on the needles if needed. Definitely clean the connections for the ammeter. When I just did mine, I actually put double nuts on the studs holding the meter to the circuit board, and then 2 more nuts to hold each of the wires on. Any bad connection there leads to heat, and that's when your ammeter melts the dash.

WOW !
Thank you
You did everything but fix it
Going to dive into it this weekend
After seeing pics I suspect the bushing if there is one where the inner cup shaft goes through bracket
It did make some squealing noises a few time before if locked up
looks like there is a set screw holding shaft in place
Any way thanks again
Great help!

 

[D Cluley]

Unfortunately, that is not a set screw, it is a oil wick. From what I can tell the magnet and shaft were inserted into the frame, and then after the brass washer was added at the bottom, the end of the shaft was peened out to hold everything in place. So, I don't think it is easily repaired.

The good news is that any '65-'66 Chrysler speedometer will work. It would not surprise me if other cars used the same mechanism, but the parts book only shows it as the whole assembly with the face plate for the '65-66 Chryslers so I don't know for sure.

Unused King-Seeley parts are out there, but a quick search didn't turn up anything for our cars. Here is a part # list if you want to dig into that.

Finally, if you replace that part with the magnet, the speedometer may need to be recalibrated. After putting mine back together with parts from a couple of clusters everything including the odometers work smoothly, but the speed is consistently about 5 mph too low. I can live with that for now.