Disconnecting the speedometer cable from transmission end

[DartGT360]

1969 Dart GT 318/904 transmission.

I have been told the reason my speedometer does not work is that I installed the speedometer cable to my 904 transmission up side down during the build.

Is this possible and if I remove it will transmission fluid drain out of the hole?

Thanks

 

[Bad Sport]

Is this possible and if I remove it will transmission fluid drain out of the hole?

Not sure what you mean by upside down.

Yes, some fluid will come out. But, if you jack up the driver side of the car and place jackstands front and rear, very little will run out.

When you install the cable, make sure you clock the housing to the corresponding number of teeth on the gear.

 

[TrailBeast]

It's not supposed to let fluid out just from removing the cable because it has seals in there.
If that was the case you would have trans fluid dripping on the legs of your tuxedo pants from the fluid coming up through the cable housing and dripping off the speedometer unit.

Now, the thing is this.
A backwards (upside down speedo cable will usually very quickly destroy itself, because backwards forces the inner wound part to unwind inside the housing and when that even starts to happen at ALL it binds in the cable housing and instantly twists all to hell.

This may actually be the case, and why it doesn't work, or that's not what's wrong with it.
Unscrew the cable from the trans and spin it counter clockwise by hand to see if the speedo moves.
If not take it loose from the speedo and make sure that end of it moves.

If you take it loose from the trans and the speedo moves, you have a gear meshing problem inside the speedo gear housing.
Could be the plastic gear is stripped, or it could be that the gear housing is not installed correctly for the size gear it has in it.

 

[DartGT360]

Not sure what you mean by upside down.

Yes, some fluid will come out. But, if you jack up the driver side of the car and place jackstands front and rear, very little will run out.

When you install the cable, make sure you clock the housing to the corresponding number of teeth on the gear.

Thanks. OK so now I have it apart. It is a blue gear and looks in good shape. I will count the teeth. When you say "clock" can you clarify what is means. When I removed the gear housing I noted it was set back as far as possible from the gear inside the tranny.

How do I know where to set the "marking" on the gear housing?

Sorry for the newbie questions.

 

[66fs]

Read the number on the gear, then look for the corresponding range on the housing and center with the bump on the transmission. Lock in position.

 

[66fs]

Here is a picture.

 

[TrailBeast]

for a gear that has 39-45 teeth.
A speedo gear with less teeth will read faster on the speedo.

 

[AJ/FormS]

Did you get it working yet?