The rapper/producer threw up a new IG post Wednesday night and he name-dropped Kim explicitly with a strong request ... namely, calling her out and telling her to take their 4 children out of the ritzy private school they all go to.

The image he posted read, "KIM TAKE MY KIDS OUT OF SIERRA CANYON NOW IT'S A FAKE SCHOOL FOR CELEBRITIES THAT ARE USED BY 'THE SYSTEM."

His caption was just as telling -- with Ye adding, "At this point everybody knows what "the system" is code word for 👀 I was removed from my dad by the system and the system removed me from my children."

KW continued ... "When the system drafts athletes they avoid working with those who have their father in their life because they are harder to manipulate. My two oldest know they daddy is."

Kanye sounded firm in his stance here, but like we said ... he quickly yanked this down -- probably after a call from Kim and her lawyers, we presume. Still, it's pretty obvious this is 100% how he feels ... and yes, he again seems to be leaning into antisemitism.

We know for a fact that Kanye has railed against "Jewish indoctrinated" schools... and we also know he's griped about his kids going to an institution he considers to be exactly this.

So, yeah -- his not-to-subtle reference to what he considers "the system" is beyond just coded language ... it's basically a bullhorn, and he's wearing his sentiments on his sleeve.

What's interesting here, though, is the fact that Ye is pinpointing two of his kids specifically and suggesting they love their dad ... namely, North West and Saint West. We've been seeing North hang out with her dad a lot lately -- and Saint pops up here and there too.

We don't normally see the 2 youngest children, Chicago and Psalm, with their dad these days -- and he's already admitted that Kim has their kids about 80% of the time regarding custody.

Sounds like Ye's grumbling about that, and perhaps feeling not as in control as he'd like.