1953 Thiokol T4T repair

[spiritsprings]

Greetings
I had an issue with the split drive in this unit
after some research I decided to tear down the unit
What I found was a reasonably simple and easy to fix problem
The outside bearings had lost their seal and let oil into the clutch
Not bad for original bearings 46 years old
no signs of wear on gears (luckey dog)
Two of the clutch housing bearings had been replaced by others
these two bearings (federal 1209ff) did not last as long as the originals
and showed signs of wear
I am installing all new bearings in this unit with quality in mind
with new clutch discs this cat will purr again
I did find two tempkin (tapered) bearings on the input shaft
the oil level ( this is very important as an overfill could result in
oil getting through the seals) do not emerse the two bearings
and being that the shaft ends bear on the outside casings
a harmonic hum could fill the air
Thanks for all your input (this is a 1963 Cat not 1953)
Mark

 

[dlmorindds]

Very nice!

 

[Thiokol2track]

Mark,
The gears and insides look to be in great shape! How did you end up getting the hubs off?? Does your wife know that you took it apart on the rug?

 

[spiritsprings]

Greetings
Maybe thats why I am no longer married. The image is taken in my shop and the parts are clean. The trick to removing the hubs are that their are two set screws one on top of each other(thanks Todd), then with a puller they came right off. I found replacement bearings at Impact Bearing. I will have this unit together by weeks end. The picture of the cat was taken on the side of the road where it broke. Nothing like a road side repair. Hopefully the snow has melted as it was all my snowmobile could do to pull that drive unit down the slope. The return trip is all uphill at 6500ft. elevation to my house.

Mark

 

[nikadog]

Mark, I have a 59 Thiokol with the dividing lane do you know if they are the same rear end? Mine looks like it has about 18 clutch pads looking at the manual. My question is I want to change the oil. What oil do you use? shell aero 50 or 80w-90 wt? How do you know when the rear end is full? thanks, Mark S.

 

[spiritsprings]

Greetings
The manual states SAE 80 or 90 hypoid differential lubricant depending on weather.
All but two bearings are sealed in the case. The two being the temkin tapered bearings on the input shaft. Those temkin bearings are not emersed in oil. There are two drain plugs on the back lower split drive case. The lower plug is the drain and the smaller plug directly over the lower is the fill overflow. With the overflow plug removed, pour the oil in the upper fill plug located on the top of the split drive unit,
it will be next to the air relief valve. I have heard many ideas on choices of oil, after looking inside of one of these things, I am going with sae 80, the manual reads to warm up the unit completely before operating. The bearings are sealed so they do not need oil, any overfill or light weight oil can find its way threw the main shafts and their bearings into the dry clutch, at that point you too will see first hand how this unit looks inside. Because the temkin bearings are above the oil fill line, they will be coated by the slinging of the oil, the thicker the oil the more it will stay on those bearings, which will also cut down on the harmonic hum. Thats my story and I am sticking to it.
Mark