Sorry it took so long to get back to you, been pretty busy. Your homework assignment is to read through these threads. We have just been through the mill with overheating problems, why's, wherefores, fixes and tests and you will find several things to look for.
http://www.automotiveforums.com/vbul...d.php?t=733129
http://www.automotiveforums.com/vbul...d.php?t=735828
http://www.automotiveforums.com/vbul...d.php?t=736576
http://www.automotiveforums.com/vbul...d.php?t=718988
"My temp gauge is running very high. The car doesn't actually overheat and boil over." I wonder how hot it is actually running because if it's not boiling over then it couldn't be
that much hotter than the normal operating temp which is around 190F.
"The mechanic is thinking the rad needs to be changed." If it is rusty then it can be cleaned with cleaner available at parts stores and it would have to be really stopped up
bad before it had to be replaced. When you replaced the thermostat, water pump and flushed the system, was it rusty water or fairly clean & green? If it was clean then I have a problem with replacing the radiator. Read through the threads and see if anything strikes a nerve and get back with us please. Try Garys test and look for bubbles but
don't take the cap off when it's hot. Take the cap off cold then idle it until it warms up and look for bubbles. Do you know if it ever ran hot enough to boil over? If so it may have blown a head gasket and you need to test the coolant for exhaust gases. It's in the threads somewhere.
EDIT: Just remembered, . . . if you can find a radiator repair shop they can use the Zoo Gun and blow out the radiator on the car. That's a funny looking gun we used years agao with water and compressed air going to it, stick it in the hose and fill it with water then pull the trigger slow then wide open andit woooshes throught the radiator or cooling system and blows everything out. You should have seen some the crud we flushed out, some of it had been there so long it looked back at us.
