Two problems related to radiator have been reported for the 1997 Nissan Sentra. The most recently reported issues are listed below.
Upper radiator hose leaks at either connection. Tried installing new radiator hose and brand new, high quality hose clamps, but problem persisted. Coolant then drips down directly into the alternator shorting the alternator out. Solution: make a cover for alternator out of sheet metal, and bolt it to the exhaust manifold cover. If water drips from the above radiator hose, the cover will protect the alternator by directing the runoff elsewhere.
Upper radiator hose leaks at either point of connection. Coolant drips down directly into alternator shorting the alternator out. Tried replacing old hose and hose clamps with a new hose and new, high quality hose clamps, but problem persisted. Solution: made own cover to protect alternator from coolant dripping from leaky upper radiator hose out of sheet metal. Bolted sheet metal cover to exhaust manifold. Now if the upper radiator hose leaks, the coolant drips on sheet metal cover and runoff goes elsewhere safely. Haven't had a problem since.