Odometer skipped ahead

[themechanic]

I restored my original non-rally gauge cluster in my 69 Coronet R/T some years ago. Since the odometer was faded and yellowed, I used the stickers made for the odometer and chose to keep the current mileage on the odometer instead of resetting it to zero. At that time I replaced the speedometer cable with a new one which I lubricated before installing it. I drove the car and verified the speedometer operated as it should and was accurate and noted the mileage appeared to increase normally.

Fast forward to a few months ago when I had the engine rebuilt. The shop recorded the mileage at 90,013 miles. When I got the car back I didn't notice right away that the odometer seems to have jumped ahead to 1200 miles until after a few drives to break-in the piston rings; That's over 10,000 miles. I know I have only driven less than 200 miles since the rebuild.

What could be the problem?

3rd photo is after restoration and just before reinstallation.

 

[pnora]

You most likely do not have the odometer wheels lock plates indexed and secured on the bar.

 

[themechanic]

You most likely do not have the odometer wheels lock plates indexed and secured on the bar.

I'm not sure what you're talking about. I removed the cylinder with the numbers and installed the stickers and replaced the cylinder. The odometer worked for years afterwards (about 1,000 miles).

 

[Sam69sat]

You most likely do not have the odometer wheels lock plates indexed and secured on the bar.

I haven't had one apart for a while but i believe this is what pnora is talking about. Those little legs need to be up against the stop.

 

[pnora]

I'm not sure what you're talking about. I removed the cylinder with the numbers and installed the stickers and replaced the cylinder. The odometer worked for years afterwards (about 1,000 miles).

If you do not understand , then what I described above is most likely what you overlooked.

 

[66 Sat]

Ferris Bueller been borrowing the car?

 

[themechanic]

If you do not understand , then what I described above is most likely what you overlooked.

Maybe. But wouldn't that be a problem right away or can it hide for several hundred miles before showing up?

 

[themechanic]

I posted photos just now.

Looks like the only way the cylinder could raise up on one side (left, in this case) is if that clip came off somehow or is missing for some reason.

 

[pnora]

Maybe. But wouldn't that be a problem right away or can it hide for several hundred miles before showing up?

Would depend on which one is out of place.

 

[Sam69sat]

If the thousand wheel (or ten thousand) doesn't have the index locked up against the stop plate, could it/they be dragged along every time the hundred mile wheel rolls over? Seems plausible.

 

[themechanic]

Would be nice if the Chrysler engineer who designed the dash would have made it so the gauges abd speedometer could be replaced without disassembling the entire dashboard.

 

[YY1]

Those "fingers" are super tricky to get back.
They all have to be interlaced with the metal of the speedometer display.
It's almost enough to make a fellow not do that job, once you start removing the wheel assembly.

 

[kiwigtx]

Ferris Bueller been borrowing the car?

I was thinking the same thing

I agree about the locking plates.....I recently had my odometer in a specialist shop to add the OE miles to the new 'NOS' km odometer......I could have done it, but I know all too well that it only takes a minor slip and the dials get all fugged up.

Only cost me about US$70 to get it done correctly. Money well spent in my book. Besides, every little bit helps keep another small business alive.

 

[kiwigtx]

Would be nice if the Chrysler engineer who designed the dash would have made it so the gauges abd speedometer could be replaced without disassembling the entire dashboard.

I think part of the reason it has been designed to be relatively difficult is to prevent odometer fraud.

Imagine if Used Car dealers could wind back odometers without breaking a sweat......

 

[themechanic]

I think part of the reason it has been designed to be relatively difficult is to prevent odometer fraud.

Imagine if Used Car dealers could wind back odometers without breaking a sweat......

True. But a knowledgeable mechanic is able to test whether the mileage is true.

 

[Roadhog51]

True. But a knowledgeable mechanic is able to test whether the mileage is true.

How many "true mechanics" are out there car shopping? I remember back in the "day" a man came around to the car lots and charged a very reasonable fee to set back the odometers!

 

[themechanic]

How many "true mechanics" are out there car shopping? I remember back in the "day" a man came around to the car lots and charged a very reasonable fee to set back the odometers!

I don't know.

If you ask to have the car independently inspected and they say no just walk away. There's always been garages who would do a PPI on a used car.

 

[kiwigtx]

True. But a knowledgeable mechanic is able to test whether the mileage is true.

Yup....can always go to Oil Changers.