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Discussion Starter #1
Hi guys,

So here I am with what may be a simple fix problem. My spedometer on the 66 with the 4 speed toploader. It works, but only after 25 and its not accurate. It more or less only starts to respond at that speed.

When I put the transmission in, I did look at the gear on the cable and it looked fine.

So what do you think? Lube the cable and see what happens? It seems to spin freely and smoothly though as is.

Is there anything mechanically in the spedometer in the dash that would cause this problem?

What do you all think?

Thanks all,
-coal-
 

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Discussion Starter #4
So after some time, I took the speedo head apart, cleaned, and lubricated it and all looks just fine. Took it out for a drive and it is still off, but works fine. I did start taking speedo gears off cars in the junk yards and trying them and see what I wind up with.

It seems that I have too tall of rear gears to have the speedo cable gear that I have. I went from what I think is a 17 tooth to an 18 tooth and the speedo was worse. So I think need a lower tooth count cable gear.

What size do I need? Toploader 4 speed, out of a 64, and what seems to be 2.75 rear gears with 225x75R15 on the back.

I do not know what size gear is on the transmission shaft.
 

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So after some time, I took the speedo head apart, cleaned, and lubricated it and all looks just fine. Took it out for a drive and it is still off, but works fine. I did start taking speedo gears off cars in the junk yards and trying them and see what I wind up with.

It seems that I have too tall of rear gears to have the speedo cable gear that I have. I went from what I think is a 17 tooth to an 18 tooth and the speedo was worse. So I think need a lower tooth count cable gear.

What size do I need? Toploader 4 speed, out of a 64, and what seems to be 2.75 rear gears with 225x75R15 on the back.

I do not know what size gear is on the transmission shaft.
Did you ever resolve this? I have the exact same problem on my 66 galaxie 500 XL conv. speedometer doesn't work initially, then pops up around 30-35 mph and starts to work. It is also inaccurate as you state. Thx for any advice toward resolution.
 

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That can also be a symptom of using a gear for transmissions other than 4-speed Toploaders. The teeth angle the other way for most others. The driven gear can look fine, but not mesh properly (of course), and just friction finally spins it. Take a quick look just to verify if that's it or not.

David

Where's Waldo? Can you spot the Toploader gear in this pic from Modern Driveline? Hint - it's the red one 2nd from the left:
 

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Discussion Starter #7
PSIG,

So what you are telling me is my driven gear is not the proper one?

I am glad CJ pony parts is close, I will be sure to stop in and see if they have a toploader gear and to see what kind of looks I get when I say its for a 66 Galaxie, to which they tell me they only do mustangs. If counter guy only knew :D

Thanks for the insight,

Coal
 

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Did you ever resolve this? I have the exact same problem on my 66 galaxie 500 XL conv. speedometer doesn't work initially, then pops up around 30-35 mph and starts to work. It is also inaccurate as you state. Thx for any advice toward resolution.
\

Similar problem with my 64, and I have the correct speedo gear.

Starts out bouncing, and then levels off around 20 mph.
 

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Thx jerrym3. So, sounds like you have not fixed yours? Is it the speedometer gear that is the culprit, or you are still researching? Thx for any help. My mechanic hasn't figured it out yet.
 

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Thx jerrym3. So, sounds like you have not fixed yours? Is it the speedometer gear that is the culprit, or you are still researching? Thx for any help. My mechanic hasn't figured it out yet.
Right now, I just live with it.

But, since I'm expecting a few items that I purchased to freshen up the instrument cluster, and the cluster itself will have to come out, I plan to lubricate the cable and cross my fingers.

If that doesn't do it, and as long as the speedo is quiet, it'll stay this way as long as I'm driving her.
 

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Most Toploaders use the passenger-side output and left-angle gear. A few do not. Some Galaxies were like this. You will have to verify your drive and driven gears to be sure they a correct for each other. That may or may not be your problem, just throwing some ideas at you. Take a look here and go to "Older Ford Left Hand Standard Drive and Driven Gears" about half-way down the page.

David
 

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Most Toploaders use the passenger-side output and left-angle gear. A few do not. Some Galaxies were like this. You will have to verify your drive and driven gears to be sure they a correct for each other. That may or may not be your problem, just throwing some ideas at you. Take a look here and go to "Older Ford Left Hand Standard Drive and Driven Gears" about half-way down the page.

David
Thx PSIG for all your help. I will research as you suggest. Thx so much. I am new to this site, and new to the world of Galaxies, so thx for all your help!
 

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OK, so maybe this is a dumb question, but I have two spare speedometers.

How can I adapt a drill to test if these speedometers also bounce at low speeds, or to test my old speedometer when I pull it out to replace the cluster?

I don't have an extra speedo cable that I could cut and fit into the drill.

Maybe I should just buy a spare cable, assuming they are available?

Appreciate the help.
 

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You can usually see if there is any damage to the speedo head with a bent halo ring or other issue. That's not likely, but might as well look. The drive is square, but uses very little power to spin, so even a coffee stir straw may wedge in there with enough grip for a good test. Some versions have the hollow drive 'shaft' exposed on the end, and a section of rubber hose can slip over it and be coupled to a handy gizmo in your drill motor.

Keep in-mind, speedo head issues are pretty rare except obvious corrosion or physical damage. Random 'skipping' or no output is generally gear related, and regular bouncing is usually cable related. However, some cable issues can be really odd, caused by a loose or poorly fit cable end, or especially broken cable strands or kinks, so carefully inspect your cable for integrity and feel for bulges before blaming the head. Finally, the cable sheath can have issues, from worn internal bulged areas the cable 'whips' into at various speeds, to a PO using the wrong grease that gets stiffer or thinner with temperature - a common problem when the wrong grease gets stiff in cooler weather. HTH

David
 

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OK, so maybe this is a dumb question, but I have two spare speedometers.

How can I adapt a drill to test if these speedometers also bounce at low speeds, or to test my old speedometer when I pull it out to replace the cluster?

I don't have an extra speedo cable that I could cut and fit into the drill.

Maybe I should just buy a spare cable, assuming they are available?

Appreciate the help.
You get a piece of old cable and clamp it into the drill, then you insert it into the speedo, then you turn on the drill....

Slow to fast very slow transition and see what the odometer reds for you :) Right hand is the correct direction.
 

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You get a piece of old cable and clamp it into the drill, then you insert it into the speedo, then you turn on the drill....

Slow to fast very slow transition and see what the odometer reds for you :) Right hand is the correct direction.
That was my first idea too, except I have no access to a spare speedo cable.

Even my buddy/mechanic that worked with me on the motor swap doesn't have an extra cable.
 

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You can usually see if there is any damage to the speedo head with a bent halo ring or other issue. That's not likely, but might as well look. The drive is square, but uses very little power to spin, so even a coffee stir straw may wedge in there with enough grip for a good test. Some versions have the hollow drive 'shaft' exposed on the end, and a section of rubber hose can slip over it and be coupled to a handy gizmo in your drill motor.

Keep in-mind, speedo head issues are pretty rare except obvious corrosion or physical damage. Random 'skipping' or no output is generally gear related, and regular bouncing is usually cable related. However, some cable issues can be really odd, caused by a loose or poorly fit cable end, or especially broken cable strands or kinks, so carefully inspect your cable for integrity and feel for bulges before blaming the head. Finally, the cable sheath can have issues, from worn internal bulged areas the cable 'whips' into at various speeds, to a PO using the wrong grease that gets stiffer or thinner with temperature - a common problem when the wrong grease gets stiff in cooler weather. HTH

David
Very interesting.
 

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Discussion Starter #19
Well I got my speedo problem figured out as best I can tell. I took the tail shaft off this evening and saw that the gear on the tail shaft was worn ever so slightly on one side. Couldn't even tell it was bad unless you felt it. Once I get it all back together I will let you know how it works.

-coal-
 
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