3.7lx new rebuild

[Frontier2002]

hi again
been battling with this build for some time .everything was replaced internally except crank and timing chain (as its no longer available)
new pistons and rings averaging about
135 psi per cylinder.
brand new head
exhaust manifold was repaired (welded and machined flat ) around the mating surface of the riser.
block checked for flatness.
this was a running motor last year until it hydrolocked and bent a rod
thing will not run
will start with alot of cranking but runs rough and stalls out .
it seems to be going down a bit in antifreeze though and cannot seem to find where it's going.
I pulled the riser off tonight and cranked it over a couple times and there was a little bit of steam (smoke) coming from the #4 exhaust port ..
could there be a issue on the intake manifold side allowing antifreeze to be sucked in from that side .....??
can antifreeze be sucked in from the exhaust side?
have new riser gaskets ordered and should be here tomorrow..
any thing else I should be checking ?
thanks