1950 Chrysler M6 output shaft/tailshaft leaking, proper re-seal proceedure

[pcxt21]

Hello all, I've got a 1950 Chrysler Windsor, 251cu engine and m6 semi-auto transmission. I just recently finished up an engine overhaul and got it back on the road, but im having trouble with a leak at the tailshaft of the trans where the parking brake drum splines into the output shaft. I've replaced the seal twice now but after both times its begun leaking again shortly thereafter.

My first attempt i drove the seal flush with the housing and upon reviewing the technical archives on this forum learned that was incorrect and the seal needs to be proud of the case to work properly, my second attempt i tried to just hammer the seal flush with the start of the splines on the output shaft but again, it leaks badly. Does anyone have a depth measurement from the case i can use to position this seal? Or know a trick to get the seal seated to the correct depth? Any insight to this would be appreciated! at $50+ a seal this has been an expensive learning process!

Edited July 20, 2023 by pcxt21

[desoto1939]

Check your service manual for your car. It might show a picture of the appropriate Factory Miller tool that was used to drive inthe seal. Sometimes you can find the tools on ebay.  The tool will have a number and it might start with C-xxxx.

 

The below picture was taken from my Miller tool catalog the tool might be the c-3105 seal install driver. verify with your service manual.

 

 

Rich Hartung

Desoto1939@aol.com

 

Edited July 20, 2023 by desoto1939

[pcxt21]

I am aware of the miller tool for installation, but so far i haven't been able to acquire it. Based on its description its just a regular seal driver that has its out lip extended so you cant over-set the seal.

 

If anyone happens to have one can you maybe post some pictures or measurements of it? I have access to some basic machine tools and at this point id probably just as well turn my own!

 

[D35 Torpedo]

You probably need a speedi sleeve. I just did my 3 speed. It took an SKF 15620 seal and 99156 sleeve. I also put the right stuff on the splines to prevent oil from wicking out.

[desoto1939]

16 hours ago, pcxt21 said:

I am aware of the miller tool for installation, but so far i haven't been able to acquire it. Based on its description its just a regular seal driver that has its out lip extended so you cant over-set the seal.

 

If anyone happens to have one can you maybe post some pictures or measurements of it? I have access to some basic machine tools and at this point id probably just as well turn my own!

 

PCTX21: I posted the pictures of the install tool but you still have not stated what specific Miller tool number that you would need for your car.  By identifying the correct tool number maybe someone can supply you with one and or even tell if one is currently on Ebay under the miller tools auction.

 

Miller made many seal drivers so the number on the driver is very important, just trying to help. I might have the appropriate seal driver.

 

Rich Hartung

[pcxt21]

2 hours ago, desoto1939 said:

PCTX21: I posted the pictures of the install tool but you still have not stated what specific Miller tool number that you would need for your car.  By identifying the correct tool number maybe someone can supply you with one and or even tell if one is currently on Ebay under the miller tools auction.

 

Miller made many seal drivers so the number on the driver is very important, just trying to help. I might have the appropriate seal driver.

 

Rich Hartung

Sorry i should have specified, I'd need the C-3105 or equivalent. 

[desoto1939]

15 hours ago, pcxt21 said:

Sorry i should have specified, I'd need the C-3105 or equivalent. 

I looked in my miller tools and I do not have this c-3105 driver sorry.

 

rich

[pcxt21]

On 7/20/2023 at 1:10 AM, D35 Torpedo said:

You probably need a speedi sleeve. I just did my 3 speed. It took an SKF 15620 seal and 99156 sleeve. I also put the right stuff on the splines to prevent oil from wicking out.

 

D35 i think your correct, i closely inspected the sealing surface on the drum and noted a small groove that even after a light polish still caught my nail. I'll double check that your suggested speedi sleeve and seal will fit my m6 and report back!

Edited July 23, 2023 by pcxt21

[Sniper]

miller C-3105

 

https://www.ebay.com/itm/284310188909

[desoto1939]

I looked at the tool that sniper just posted that he found on Ebay.  i do not think this tool will work. Note that this toolis labeled as SP-3105  and the tool you want is numbered as C-3105.  The C-3105 is a special drift to force inthe seals as a complete outer circle to matchup with the outer edges of the seal. The tool on ebay is not useable to do the job that you are looking for.

 

Rich hartung

[Sniper]

dang it, you are right I snafu'd that one, lol

[Dodgeb4ya]

The C-3105 won't do much good postioning a modern seal as modern seals are made differently than the original MoPar seals.

Reason being seal lip position, seal thickness etc.

The original rear trans seal is roughly 3/4" thick and has both leather and felt sealing materials used...

The new modern seals have two thin rubber sealing lips and are generally 1/2" thick.

The original C-3105 tool will work on the new seals but cannot drive them flush if needed.

What is most important is to locate the seal lip on a perfect groove and pit free area of the machined companion flange hub. Use a speedi-sleeve if necessary.

The other issue is to drive it in not too far but enough so the face of the seal is away from the companion flange.

If not when tightening the companion flange onto the output shaft the seal will get caved in with out you knowing it.

This happens all the time on the inner seals on rear axles in our old MoPars.

The last issue with these modern replacement thin tin seals is to use a round flat edge driver that only pushes on the outside edge of the seal. Steel pipe, bearing race, proper size cup driver etc.

Using a hammer and or hammer and a drift will distort these new thin to win seals which can slightly cave the seal face and seal lip inward causing leakage.

Easy on the hammer blows...

Use some grease on the seal lip, #2 Permatex on the companion flange splines and OD of the seal....

Or your choice of sealant.

Check to be sure the lip spring is still in place.

Get'er done!

 

[pcxt21]

Hi all just wanted to wrap up this thread, as D35 and Dodgeb4ya suggested I installed a speedi sleeve and a modern SKF seal which completely solved my leak issue 1000 miles later and shes still bone dry. Thank you all for your assistance and feedback!