1953 Belvedere overdrive

[rusty_apache]

I’m in the process of removing the relay, cable assembly, carburetor switch and overdrive unit from my 1953 parts car to install in my 1952 Cranbrook club coupe. 
It looks pretty straightforward other than the hole in the transmission hump for the Governor assembly. 
I believe that I can retain the 32,000 mile 1952 three speed and simply add the overdrive in place of the tailpiece, but wanted to check with you knowledgeable people to be certain that is possible. 
 

I’m also wondering if the 1953 carburetor kickdown switch mounts work on the 1952 carburetor?

Any words of caution or advice would be greatly appreciated!

 

Edited May 26, 2022 by rusty_apache

[Dodgeb4ya]

It's all a direct bolt in swap.

No hole in the hump required for your 52.

[rusty_apache]

I was hoping the 1952 had an ample transmission hump and it wouldn’t need surgery!

So the 1952 three speed can be used along with the overdrive or do I need to use the 1953?

[kencombs]

The main case on an OD transmission has a hole for the reverse lockout function that is missing on a non-OD case.  I guess one could make one IF  you can locate it precisely.

[James_Douglas]

The main shaft if different between the non-OD and the OD units. You would have to gut the old unit no matter what. If it is out, just rebuild the 1953 unit with the OD and then put it in. See my long threads on the rebuilding of my units both in the last few months and around 2006.

 

I have another on the bench that that to put together in the nest few weeks. I also posed a week or two back a spread sheet with all the bearing and seal numbers.

 

James

[rusty_apache]

Thanks for the information guys! It’s a great help.

[rusty_apache]

Okay, I probably should have asked first but I was trying to accomplish something before posting a bunch of questions. 
So I separated the overdrive from the three speed, thinking it was like the Chevrolet setup and I could just grab it and leave the 3-speed in place. 
Now that I understand Mopar used a dedicated three speed I want to bolt the units back together to keep debris out of them as much as possible during cleanup. Unlike 33,000 mile “Ralph Cranbrook” the Belvedere has 116,000 along with the obligatory baked on grease/gravel/sand. 
I’ve tried shifting into all the gears and neutral and have spun both shafts as well as throwing the overdrive cable arm in both directions and paid close attention to the shift rail stubs that stick out of the overdrive. It originally separated about an inch or so and I was able to get it to mesh back together except for about 1/4”. 
I installed the bolts to hold it together but the input shaft begins to bind when I barely tighten the bolts. 
 

Could it be that I need to operate the O/D pawl to get the cases to close? It’s 100 degrees out right now so I’m not going to test the theory until dark:30.

 

 I did watch the 1952 training slideshows and they were a great help understand Mopar’s approach. I’m going to go through the 1953 starter because I believe Ralph has the unimproved starter bendix. 

I also have been doing some digging and found Mr. Douglas’ PDF of the parts list so my local bearing supplier will appreciate that! 

I also picked up on another comment about Studebaker using the same unit. I have an extra Deluxe Starlight coupe for parts so if need be I can possibly use it’s overdrive components. 

[DJ194950]

Well the can of worms has been opened wide and you will need to do a complete tear down of the 3 speed trans as bearings have fallen out at the front end of the main shaft at the front inside of the three speed. (Most likely).  Mopar trans insides are often different from other brands and the OD portion is also different and you will need to follow Mopar only assembly instructions.

 

Probably needed to be done anyway but now it is for sure.  The 3speed gears and internals will interchange except the main shafts IF the synchro set ups are of the same type.

 

DJ

[rusty_apache]

Thanks DJ,
It’s good to know not to torture it any further! I’ll just shove some rags in the gap and scrape off the crud instead of pressure washing it. 

[James_Douglas]

To get the OD in and out there is a very fussy procedure where you have to pull the cable arm out of the case a bit to get it to come or on. Do to the Imperial Website and read over all the repair booklets.

 

James

[rusty_apache]

Thanks, I will check it out as well.