1998 Buick Skylark Owner's Manual - Page 248

Adding Coolant Surge Tank Pressure Cap If you need more coolant, add proper DEX-COOL@ the coolant mixtureut the surge tank, but only whenthe engine is cool. Your pressure capis a 15 psi (105 kPa) pressure-type cap and must tightly installed to be prevent coolant loss and possible engine damage from overheating. When you replace your surge tank pressure cap, a GM cap is recommended. You can be burned you spill coolant hot if on engine parts. Coolant contains ethylene glycol, and itwill burn if the engine parts are hot enough. Don't spill coolanton a hot engine. When replacing the pressure make sure it is tight. cap, Thermostat Engine coolant temperature controlled by a themostat is in the engine coolant system. therrnostat stops the The flow of coolant through the^ radiator untilthe coolant reaches a preset temperature. When you replace your thermostat, ACDelco@ an thermostat is recommended. 6-25