Speedometer Drive Assy

fixitphil

Member
I have a lot of slide (about 1/2") in my drive gear on my Main Drive Gear Shaft.
This is noticed when the Speedometer Gear and Cap Assy. are removed. I've been told that there should not be that much play (slide) in the Drive Gear for the speedometer. Also told that probably the retainer (ring) is either broken or was never in place after a transmission overhaul.
Another theory: I've also been told that the retainer (ring) does not have to be in place as it was only there to keep the gear in place as the new engine was hanging vertically on the way to installation at the factory.
I'm totally confused with several different theory's. Help!
 
From what I understand the retainer ring was only required to keep the gear and bearing in place when the complete axle was transported with the torque tube, which was hanging downwards on its way to the assembly line, it saved time installing the parts on the assembly line, thus keeping the line moving.
 
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I've heard the same thing Brian. I have a friend that insists that I replace that retainer and that is going to be a big job, maybe not worth the effort.
So I'm getting my speedo overhauled and a new cable in place, and then all should be well.
Thanks all,
Phil
 
I have a lot of slide (about 1/2") in my drive gear on my Main Drive Gear Shaft.
This is noticed when the Speedometer Gear and Cap Assy. are removed. I've been told that there should not be that much play (slide) in the Drive Gear for the speedometer. Also told that probably the retainer (ring) is either broken or was never in place after a transmission overhaul.
Another theory: I've also been told that the retainer (ring) does not have to be in place as it was only there to keep the gear in place as the new engine was hanging vertically on the way to installation at the factory.
I'm totally confused with several different theory's. Help!





You should not have a 1\2" of play with the speedo drive gear on the drive shaft. I suspect the last person that had the assembly apart neglected to install the grease seal (it is about 1\2" thick). This would allow the bearing race and bearing to drop down that amount.


The attached article shows the assembly.


Tom Endy
 

Attachments

Thanks Tom for all your help.
How do I disassemble these parts?
I have my engine out now. Do I have to pull the rear end to get to this assy? How do I pull the bearing race out and how do I realign the race with the dimple?
 
About 15 years ago just about all of the suppliers sold a reproduction roller bearing race that was just terrible. Besides being made of poor quality material, it did not have the important dimple to lock it in place. Bratton's finally had a correct race made and several other suppliers followed. However, probably hundreds or thousands got out into the world, and some suppliers probably still sell them.


To answer your question on how to: Go to the web site of the Santa Anita A's of Arcadia,California at www.santaanitaas.org. On the home page put your cursor on "Technical Reference", my name will drop down below, click on it. It will bring up a technical library. Scroll to the differential section and you will find numerous articles that should answer any question you have about the rear axle assembly. They are all PDF files and you are welcome to download any of them.


Tom Endy
 
Boy that sure answers my question. You have a way of writing instructions that simplifies the job at hand.
Your instructions on other repairs on a Model A have come in so handy and are so self explanatory. I know you've helped hundreds of A'ers throughout the years.
Thanks again for all,
Phil
 
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