I have a 1992 cadillac deville.i have a problem with the water going from radiator to the water reservior after it driven for awhile.what could the problem be?

Let the engine cool, remove radiator cap, start the engine let it warm up.
Make sure the radiator is full. Look in the radiator for a bubbling mist. that is the sign of a bad head gasket. Also caddies with aluminum blocks require special coolant.

I believe you are correct - the radiator is probably plugged, but you should also check the water pump.

ENGINE COULD BE OVER HEATING.REPLACE THERMOSTAT AND RADIATOR PRESSURE CAP.MAKE SURE YOU HAVE 50 /50 MIXTURE ANTIFREEZE AND WATER IN THE COOLANT SYSTEM.

You may be getting it from the oil or trans. cooler in the radiator. Get a donor radiator from pullapart.

The bearing are bad in the water pump. It will need to be replaced.You will need a special tool that is available at most parts stores to removed the screws. Good Luck!

check fan fuses and relays. is the idiot light coming on . stop engin temp. if its coming on unplug it . its located behind the rear valve cover in the middle. if that isnt it replace temp sensor. located below the air breather.

The fan is still going. They will do this for a while to cool off the radiator after car is shut off. If it last for a very long time, the relay will have to be replaced.

Northstar? If so get one at your local auto parts store!

could be a wheel bearing

Water pump is located on rear of the engine. faceing the car it is between the radiator and the head. It is driven by a small belt. It is removed by removing a cover plate that has the radiator host and by pass hose connected to it. it takes a special tool to remove and install this item. it is available at most auto stores. approx. 2 hour job and somewhat a hard job . see the haynes manual for this car very detailed on how to change the waterpump. jim