smelling rad fluid

I have a 90 SC that I am having an odd problem with. When the temp gauge gets to temp and the fan kicks on I smell rad. fluid. When it goes off I don't smell it anymore. It doesn't over heat. I've put a drip pan under it for days, and no leaks. I've been under the car for over an hour or more and don't see any proof of rad. fluid anywhere. The catch can stays were its suppose to. There's no leaks inside the car,the heater works fine,so I know its not the heater core. Anyone have or had this problem, or any ideas??? I've had the car in heavy traffic and when the fan kicks on it cools down quickly between cool and temp. and doesn't come on frequently. I know its not the HG, I've checked the oil, and changed it: not milky-no water in the oil. Thanks, JDC

i'd say you've got a leak in your top end tank... it only leaks under pressure and when the antifreeze level rises high enough to leak out... the fan lust blows the smell your way, and probably aids in vaporizing it.

get a uv dye kit and check for traces.

>The catch can stays were its suppose to.

This is only a reliable observation IF the transfer tube from the radiator to the overflow tank is not blocked...because if it is, the amount of coolant in the overflow tank will not change, regardless of what's going on in the engine.

Does your upper hose collapse when the car cools down?

Checked for leaks near the bleed tube at the thermostat housing...top and bottom...?

smell rad fluid

Sorry for not getting back but I went and got some dye for the rad. I put it in, got it up to temp used UV light and there it was. It was on the top inlet tank. It was in the little trough like on the inlet tank not much but enough to see it with the UV light. If I didn't get the dye I would not have seen it. I would like to thank you two guys for the help. Thanks JDC