dansf100

So, 90 Civic with the D16A6 Automatic that I bought a month ago. Had a problem with it starting hard and idling bad, so in the course of that fix, I've replaced the thermostat w/ gasket, both coolant temp sensors in the head, and while I had the radiator out, I flushed it the best I could with garden hose on full. Problem is this....noticed that the radiator fan is on constantly. Gonna diagnose that tomorrow....may have been hard wired to stay on. Went for a drive through town today, and the temp gauge spiked all the way into the red. Turned on the heat way up, finally cooled a bit. Got it home, parked with engine running, and the temp goes down to normal. Cracked the radiator cap to check fluid level....it needed about a pint. Cracked the air bleeder screw to let out air...nothing happens. Radiator hoses don't feel overly hot. Radiator is hot on half with no fan, fairly cool at fan. Strange part is...with every other car I've ever owned, you could see the coolant flowing through the radiator by looking down through the opening for the cap......can't see anything but still water in this one. Could the water pump be out? It's not leaking water from the weep hole, and I only hear a very faint sound coming from the timing belt area but I don't believe it to be the pump. Besides, if the pump was out, wouldn't it make the car overheat all the time especially at idle? Any help would be great here.

4drEF

When did the temp spike? While driving or while at stops?
When it was HOT did you pull over to 100% make sure the fan was on? Is the fan spinning the right way?

If it was all hooked up properly and overheating is happening when you are driving and not when you are stopped then I figure either you to thermostat isn't installed correctly or your radiator is dead.

KWayRacing

or the head gasket is blown.