Finding a modern cap that will fit seems to be impossible.
I did find a source of NOS 125v 88-108 mfd motor start caps that seem to work fine.
1" dia x 2.4" long so they fit OK.
Mine came quickly and were very well packed.
It turns out that these are Teletype Part 181384 as used in the M33. Also suitable as a substitute for 162074 used in 1/40 HP miniature motor M28 TD and ROTR equipment (I just cut the wire leads short and soldered to them).
They also work OK in the 1/20 HP motors in the 28KSR and 28RO. Not the correct value but I have replaced several with no issues. I haven’t tried them in the 1/12 HP motor in the 28ASR which uses yet another value cap.
The motors with bad caps would just sit and tremble until I gave the fan a quick pull and then they would spin up OK.
YMMV, no warranty, etc.
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