Nissan Skyline/Stagea V35/M35 infiniti G35 coolant issue

[PhilthyPhil]

Hello
i have a 2002 Nissan Stagea with VQ30DD engine(much the same as a VQ35de) has mechanical viscus fan
it boils within 10 minutes of running
i got the car as unknown
i have had the air bleeder fixed( replaced with brass Bleed T joint)
radiator top tank replaced(warped top tank) and radiator flushed(7% blocked)
NEW nissan thermostat(old one didn't open possibly got cooked)
i have checked the water pump and is NOT leaking and DOESN'T have play or wear
the engine has no real rust(hardly no rust on the water pump impellers had clean fresh coolant

it gets hot and boils within 10 minutes even when bled
it DOESN'T blow bubbles, it runs on all 6 , no misfires, no issues with a leak down test, no combustion gasses in the water, no water in the oil, no oil in the water, trans and coolant in radiator are separate(not leaking into each other)

i cant seem to find why its BOILING within 10 minutes
i have noticed when removing the top hose the water is NOT flowing out the top hose when run the engine, and that even when i remove the guts from the old thermostat it still doesn't flow out the top radiator hose, meaning it doesn't have any water flow, it clearly says to me that the water pump impellers were rusted or missing or it was spinning on the shaft on the water pump, but when removed and inspected it 100% fine nothing wrong with it
also when full with coolant and bled, if you squeeze the bottom hose by thermostat you can hear air by the fully cut open thermostat(meaning that air is in the housing or it cant bleed which is impossible at that location), more is that without a thermostat the engine will and should self bleed straight away, i have bled and taken for a quick drive and jumped on the brakes really hard to dislodge any trapped air and i have even gone backwards and did the same, it is 100% bled and still will boil
i have owned a lot of these V35's and no issues, this is a first

if anybody might have any idea why it boils and doesn't have water flow or have had this issue be i would love to hear
Cheers
Phil

[VStar650CL]

Check the lower hose for a collapse from internal delamination. In Nissan systems the main thermostat and lower hose have suction on them and not pressure, so if the hose delaminates, the water pump will suck it shut and nothing will flow. The water pump also can't suck from a pinched straw, you may just have a blocked radiator. Lastly, the early VQ's had a "water control valve" in addition to the main 'stat. I don't know if your VQ30 has one, but if it does, that will kill all flow through the block if it's stuck shut.

[PhilthyPhil]

where will the water control valve be?
it has a water bypass on the rear of the new thermostat
the radiator has been flushed by the radiator services, it was only 7% blocked
i will remove the lower hose and check it, yeah i have seen that on my R31 skyline when it had a 78% blocked radiator, the lower hose sucked flat even squashed the rusted steel spring inside it haha

[VStar650CL]

The WCV (if it has one) will be in the crossover plumbing. Take a look at LC-19 here, it's a Pathfinder but if you have a WCV it should be in a similar spot. I'm pretty sure only the axial VQ's ever used them, the transverse ones didn't.
https://www.nicoclub.com/service-manual ... 2%2Flc.pdf