John,
Intersting question! You have worked on a lot of older machines than I have, and and thus you may be aware of more Tee bearing designs than I am (for example, the one you mentioned with a set screw - I've never seen one of those). That said, here's what I can tell you:
The oldest machine I've worked on in great detail is a 1960/1961. It had the non-set-screw bronze bearing with the retainer ring/C-clip underneath it. That machine showed signs of work, so the gearcase may not have been original. It did have a keyway on the agitator shaft for the drive block vs. splines. The newest machine that I recall in detail having the bronze bearing was a 1967 Kenmore 70, which I rebuilt including bearings in 1991. I remember that one well because I had only seen plastic tee-bearings prior to that one and remarked about it.
Most of the machines I worked on in the early 90s had the black plastic tee bearing which fits on the same C-clip as the previous bronze. These would all have been 1970s models. I remember one in particular very well as I installed the black bearing upside down, which looking back was funny...but not so much at the time. I suspect that these came about with the fast brake design in 1971, however I am not certain. Everything I saw from then until the second half of the 70s had the black bearing.
It wasn't until a 1978 model, or so, when I discovered the beige/ivory colored plastic tee bearing with the retainer ball. If that is right, that would coincide with the evolution of the short centerpost. I don't know if the two are connected, but until I got used to securing those retainer balls in place with a dob of grease, I was forever cursing them because they fall out, sometimes at the most inopportune times...they work great though when you know how to use them properly.
So, I'd say bronze until the late 60s or so, black plastic until late 70s, and the light plastic thereafter.
As to the shaft configurations, I do know that some of the mid 70s machines only accomodated the C-clip and had no holes for a set-screw or ball. Learned that one the hard way too because I went to do a gearcase swap and didn't have all the right parts one time. That flippin' clip/retainer ring was a pain trying to marry onto the agitator shaft until I learned how to do it. If memory serves this was a standard capacity 1976 built Kenmore. I don't think machines were made very long this way however (with just the clip only). I have a carbon copy of that machine again now - it might be an interesting thing to check sometime.
You brought up an interesting thought though with this, as it relates to Duke's machines. Duke...if your tee-bearing on the 1972's transmission is black plastic, you won't need the retaining ball and your machine never had one originally. When you said something about the missing ball, and it being a possible replacement transmission, I just assumed you had a newer gearcase with the light colored bearing and never considered that the '72's original gearcase would have the black plastic one. If it does, then both transmissions should have the same retainer clip and you'd be golden to use either tee bearing in either machine. ALSO, if that is an original '72 gearcase, then you may have had the same spring and clip on both machines to secure the rear-facing side of the basket drive yoke/plate. Big hands don't fit in there well, I know, but to get the right spin, you must re-secure that pin in the groove on the support shaft. The belt gets in the way...
I was complaining to Andy in April at Kevin's wash-in, while working on his 1966 Lady K, that these springs were a pain, and his installed properly, the first time, lol. I've sent those springs flying across my garage in trying to fenagle with them, so be mindful of that. I usually use a flat bladed screw driver to compress the spring a little, and needle nose pliers to insert the cotter pin.
Gordon
Intersting question! You have worked on a lot of older machines than I have, and and thus you may be aware of more Tee bearing designs than I am (for example, the one you mentioned with a set screw - I've never seen one of those). That said, here's what I can tell you:
The oldest machine I've worked on in great detail is a 1960/1961. It had the non-set-screw bronze bearing with the retainer ring/C-clip underneath it. That machine showed signs of work, so the gearcase may not have been original. It did have a keyway on the agitator shaft for the drive block vs. splines. The newest machine that I recall in detail having the bronze bearing was a 1967 Kenmore 70, which I rebuilt including bearings in 1991. I remember that one well because I had only seen plastic tee-bearings prior to that one and remarked about it.
Most of the machines I worked on in the early 90s had the black plastic tee bearing which fits on the same C-clip as the previous bronze. These would all have been 1970s models. I remember one in particular very well as I installed the black bearing upside down, which looking back was funny...but not so much at the time. I suspect that these came about with the fast brake design in 1971, however I am not certain. Everything I saw from then until the second half of the 70s had the black bearing.
It wasn't until a 1978 model, or so, when I discovered the beige/ivory colored plastic tee bearing with the retainer ball. If that is right, that would coincide with the evolution of the short centerpost. I don't know if the two are connected, but until I got used to securing those retainer balls in place with a dob of grease, I was forever cursing them because they fall out, sometimes at the most inopportune times...they work great though when you know how to use them properly.
So, I'd say bronze until the late 60s or so, black plastic until late 70s, and the light plastic thereafter.
As to the shaft configurations, I do know that some of the mid 70s machines only accomodated the C-clip and had no holes for a set-screw or ball. Learned that one the hard way too because I went to do a gearcase swap and didn't have all the right parts one time. That flippin' clip/retainer ring was a pain trying to marry onto the agitator shaft until I learned how to do it. If memory serves this was a standard capacity 1976 built Kenmore. I don't think machines were made very long this way however (with just the clip only). I have a carbon copy of that machine again now - it might be an interesting thing to check sometime.
You brought up an interesting thought though with this, as it relates to Duke's machines. Duke...if your tee-bearing on the 1972's transmission is black plastic, you won't need the retaining ball and your machine never had one originally. When you said something about the missing ball, and it being a possible replacement transmission, I just assumed you had a newer gearcase with the light colored bearing and never considered that the '72's original gearcase would have the black plastic one. If it does, then both transmissions should have the same retainer clip and you'd be golden to use either tee bearing in either machine. ALSO, if that is an original '72 gearcase, then you may have had the same spring and clip on both machines to secure the rear-facing side of the basket drive yoke/plate. Big hands don't fit in there well, I know, but to get the right spin, you must re-secure that pin in the groove on the support shaft. The belt gets in the way...
I was complaining to Andy in April at Kevin's wash-in, while working on his 1966 Lady K, that these springs were a pain, and his installed properly, the first time, lol. I've sent those springs flying across my garage in trying to fenagle with them, so be mindful of that. I usually use a flat bladed screw driver to compress the spring a little, and needle nose pliers to insert the cotter pin.
Gordon
