1UZ Fluid Flow Paths


New Member
1UZFE_Deck.jpg Hi all, new member here. I have a bit of an off the wall 1UZ-FE question... What are all the holes for on the deck of the cylinder block? I mean I know, or can guess, some of them, but I'd like a little more accurate info if anyone has it. I've attached a picture of the block deck surface and here's my best guesses:

Blue: Cylinder head bolts
Red: Oil - the 4 on the bottom are drains back to the sump, the "d" shaped one on the right is supply to the head
Black: Coolant
Green: No idea (this is the one that's the biggest mystery to me)
Purple: I know there are head bolts there but there's also these "pipe" looking things that protrude up out of the block around those holes. Do they serve a purpose, like letting coolant or oil flow, or are they just there to align the head on the block or something like that?
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