Checking the Radiator for normal operation

[xraven]

Hey all, (Searched forum - no info found)

I am trying to find out what are the signs of a normally functioning radiator before I go out and get a new one.

I have a 240sx '89 with a temperature issue Here is a representation of the reading on the gauge the x is where the needle sits. H **=x======*C

The gauge sits there solid, but will drop about 1-2mm when I go on the highway(80-90km/h), but will then go back and sit tight right where I showed above.

The needle never goes above into the**'s to the right of the H. The temperature sensor for the display is new so the temperature is correct. The system has been bled correctly, new thermostat, no coolant in oil, no oil in coolant. No visible leaks.

What I need to know (hopefully someone knows) is what to look for to see if the radiator needs replacement. The top of the radiator gets hot , you can take the cap off and the coolant gets fairly warm. It fills and draws from the reservoir. After leaving the car sit after idling or driving, should the fins on the radiator feel warm? The top and bottom of the radiator fins are cold as the body of the car. It's definitely overheating, because the engine lacks power and idles quite rough once the temperature rises.

The performance of the engine is mint when the temperature is mid to low.

Ideas - raditator toastyied or did I blow my headgasket or worse ?

[180fan]

you probably have a blockage somewhere. Not enough to make your car overheat all the way but enough to keep it uber hot. Try a new radiator if you suspect it, if you've never replaced it, I'd suspect it... HG, check your oil. If it's milk coffee colored, you're in trouble.