1993 Cadillac DeVille Owner's Manual - Page 293

Add coolant m x at therecovery tank, but be i careful not to spill it. - A CAUTION: You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol, and itwill burn if the engine partsare hot enouglspill coolant on a hot e-yine. I RADUTOR PRESSURE CAP must be tightly Installed toprevent coolant loss and possible engine damage from overheating. Be sure thearrows on the c line up with the overflow tube on the radiatorfiller neck When you replace your radiator pressure cap, an ACS cap is recommended. THERMOSTAT Engine coolant temperature is controlled by a thermostat in the engine flow of coolant through the coolant system. The thermostat stops the radiator until the coolant reaches a preset temperature. When you replace your thermostat, an AC@thermostat is recommended.