Early TorqueFlite Speedo

[Stumper]

So, O ring and seal for my leaking speedo came today from Brewers. I pulled the adapter out and was surprised by what I found (aside from the flood of fluid).. I’ve never had the Speedo pinion out on an early 727 and they are quite different from the later non cable transmission. A few things I see that don’t look right. One is the small O ring in the picture. I Don’t see this in the TM diagrams? Is it supposed to be there?
The grooves on the plastic gear also look a mess. I don’t supposed the teeth are supposed to be cross hatched like that?? Wonder what did it?
Also, is the retaining clip groove on the metal end supposed to be spiral like that??

 

[R/T Boy 67]

The gear has to go on a lot further. The clip goes over the top shoulder. It is no wonder the gear is pooched.

 

[Stumper]

The gear has to go on a lot further. The clip goes over the top shoulder. It is no wonder the gear is pooched.

I had already pulled the gear off. Was just holding it there for reference. Is that small O ring supposed to be there?

 

[R/T Boy 67]

I can't see any reason for it. It might have been stopping the gear from sliding up far enough, which caused the poor engagement. Play around with it a bit, with and without the O ring and see if it interferes with the gear.

 

[lewtot184]

that's the wrong gear. the angle on that gear is in the opposite direction of what you should be using. what your thinking is an "o-ring" is probably what's left of the rubber seal that goes inside the pinion. change the pinion and add a new seal inside the pinion.

 

[Stumper]

The seal was still intact in the gear tube. The small O ring is an extra piece. I am ordering a new pinion right now. That one was an 18 tooth but Brewers figures a 19 tooth would be a better fit (3.23 gears and 27-27.5” tires)?
I’m not sure why a pinion would exist with reverse angle teeth?

 

[Stumper]

that's the wrong gear. the angle on that gear is in the opposite direction of what you should be using. what your thinking is an "o-ring" is probably what's left of the rubber seal that goes inside the pinion. change the pinion and add a new seal inside the pinion.

I ordered a new 19 tooth pinion from Brewers and the teeth on the new one definitely go in the opposite direction.. Any thoughts as to what the one I took out might have went to? From all I see it appears exactly the same except the teeth are reversed..

 

[Stumper]

Just an update. Replaced the pinion with a new 19 tooth from Brewers - with the correct tooth angle. New seal and ring. No leaks and the speedometer is not jerking . Still no idea what the pinion that was in it might have been for ( maybe a manual trans?).
Now I move up to trying to stop the leak at the shift cable..

 

[khryslerkid]

This seal likes to leak also and it's right above the shifter cable.
https://www.forbbodiesonly.com/mopa...p-new-residence.114133/page-34#post-911546492

 

[khryslerkid]

A lot of shifter cables leak where the plastic housing is crimped into the end. Clean it up real good (Brake Clean will work) and slide a section of shrink tubing over it. Use the shrink tube that has glue inside of it. I found my last tubing like this at Home Depot.

Here's the best info for removing and adjusting the cable.
https://www.forbbodiesonly.com/mopa...ht-transmission-cables.209416/#post-911768297

 

[Stumper]

I saw the posts about the shrink tubing. What end of the cable do you need to slide the tube over - I assume the upper end?

 

[Nate S]

Sorta late now but for the record, the 19 tooth is what the factory used with 27” tires. I compared mine to gps and found it to be running fast. 20 tooth would have made the odometer right, 21 would make the speedo right. No way to get back the 5000 extra miles on the odo but I figured I’ll make the speed right and in another 80k miles the odo will be right too, or at least the total will be correct.

 

[khryslerkid]

I saw the posts about the shrink tubing. What end of the cable do you need to slide the tube over - I assume the upper end?

There are different shrink tube that shrinks more than others. The heavier tubing that has the glue in it shrinks about half its diameter in most cases. That said you might be able to remove the adjusting wheel and slide that diameter tubing on from that end. I don't remember which end I did mine from mainly because I originally had the whole cable removed. IIRC the first attempt I used the tubing without the glue and it still leaked a little. Second attempt I found the tubing with glue and slid it on the transmission end with the adjusting wheel removed. That's what I'm thinking.

 

[Stumper]

There are different shrink tube that shrinks more than others. The heavier tubing that has the glue in it shrinks about half its diameter in most cases. That said you might be able to remove the adjusting wheel and slide that diameter tubing on from that end. I don't remember which end I did mine from mainly because I originally had the whole cable removed. IIRC the first attempt I used the tubing without the glue and it still leaked a little. Second attempt I found the tubing with glue and slid it on the transmission end with the adjusting wheel removed. That's what I'm thinking.

Thanks! I’ll have to look around for some of that heat shrink. Do you recall where you got it.?