
Thanks.
Yeah, I'd assume it would slip/spin without the set screw.
Same here. I've never noticed any selector jamming or any sort of internal sticking/binding. I've never opened up my Zeal ratchets before as I've never felt the need to.
I think the feel of the selector lever might be due to the fact that the Zeal mechanism is unlike other floating pawl mechanisms, as well as the fact that it uses a really low spring rate.
36-tooth Zeal ratchets were never meant to be "Snap-on killers/replacers"

They aren't marketed as such by Ko-ken and I don't think the users tout them as such either. It would be ridiculous if they did.

There's a place and need for high-tooth count ratchets, but there's still a place where low-tooth count ratchets can perform effectively.
I never thought of this until typing this reply.....
If one were brought up using modern 72-tooth ratchets from the very beginning and nothing lower, I can see why they'd balk at the thought of using a coarse-tooth ratchet. 24 or 36-tooth Ko-ken ratchet probably seems archaic by comparison, and anyone using them today has got to be old.
Oh, FWIW, I had the opportunity to play with probably around 30 Zeal ratchets, 3/8 and 1/4 drive, in all styles. I wanted to do a quality check on the ratchet mechanism of each ratchet that was on display at the store. To my surprise I did find one 1/4 drive Zeal ratchet that had a slight issue.
What I do is free spin the anvil one full turn and note whether the back drag is consistent throughout, and even between eachother.
I can tell you that the back-drag is consistent on each and every ratchet (can't say that with tool truck brands!).
It was just one ratchet that exhibited a slightly higher resistance at one particular section (maybe 10* degrees) of the gear.
The result of my inpromptu quality check was that:
the ratcheting feel was consistent throughout, in both 1/4 and 3/8 drive
Ko-ken products aren't devoid of flaws, as small as it may be, what I noticed was still a flaw