My 90 Crx B16A swap starting running hotter than normal. It used to run at 190 with 180 thermostat and now runs at 220. I have replaced it with a 180 degree thermostat 3 times thinking I might have a bad one (last one was upgraded to 180 Stant Superstat premium) and have installed a brand new radiator and it still runs 220 degrees even on the coldest nights cruising down the open road. Lower radiator hose that connects to thermostat housing stays cool to touch and does not warm up. I have an Auto meter aftermarket temp gauge for my readings. The heater will run you out of the car so I know I have good flow through the heater core. Is there anything that could cause a restriction or low flow?

 

If your thermostat is working properly, it could possibly be a clog somewhere between the motor and the radiator/clogged radiator, or maybe the water pump isn't in proper working order. If it's a clog you might need to pressure flush the radiator or entire coolant system.

Make sure to replace your engine coolant at regular intervals, as specified in the vehicles owners manual, with the correct coolant/water ratio to help prevent clogs and to prolong the life of the water pump.

 

leak down test, could be signs of a blown head gasket...

 

Dose your fan turn on, it sould turn on about 5min after start up once the
vehicle reaches temp.

 

my fans come on at normal temp and i have no leaks i had a honda mechanic tell me the water pumps going bad because the lower hose never gets warm. so my guess is my water pump cant push enough water to get it through the thermostat.