I have a 1990 n/a, and it runs very hot consistently. It will sit as high as 225 on the highway, and will cool down maybe 10 degrees at low RPMs. It is not losing water, the thermostat in or out makes no change, I have verified temps with an autometer gauge and a laser thermometer. The radiator is an all-aluminum three-core unit that also did not make a difference. I have an electric fan that pushes through, and a fan that pulls through. I have run with a shroud, without a shroud, and I just don't know what else to try and inspect or do. i have two bleeders in to get out any air pockets. I am officially out of ideas.

Please throw some ideas at me, I am looking for further outside the box.

Thanks,

-d3

Blocked coolant passages, clogged radiator (crap will break off in the coolant passages and clog the radiator), Bad fan clutch, crap between the AC condenser and rad (leaves, dead bugs, etc.)

Edit: Radiator is new and installed after overtemp started.

Just a thought here.

How old is the water pump? When you say "It is not losing water", does that mean you are only running water in the cooling system?

When I did the water pump on my JDM engine, it was running only water for some reason. The pump impellers inside were corroded/eroded to about 1/4 the size of a new unit. I wish that I took a picture of it back then.
Maybe worth a consider too if all other option don't resolve the issue.

Worn blades on water pump, interesting solution! I wonder if there is a way to measure flow without taking the front of the engine off to inspect. I have an android camera borescope, maybe I could snake it in to take a peek.

Blades on the water pump could be worn. Also many folks have ran into overheating when running electric fans. The fans need to move a lot of air in order to be viable