1998 Buick Riviera Owner's Manual - Page 265

Thermostat Engine coolant temperatureis controlled by a thermostat in the engine coolant system. thermostat stops the The flow of coolant through the radiator until the coolant reaches a preset temperature. When you replace your thermostat, GM thermostat is a recommended. When to Check Power SteeringFluid It is not necessary to regularly check power steering fluid unless you suspect therea leak in the system is or you hear an unusual noise. fluid loss in this system A could indicate a problem. Have the system inspected and repaired. The power steering fluid reservoir the L67 engineis on located below the generator and behind accessory the drive belt. Power SteeringFluid How To Check Power SteeringFluid When the engine compartment cool, wipe the cap and is the topof the reservoir clean, then unscrew the cap and wipe the dipstick with a clean rag. Replace the cap and completely tightenit. Then remove the cap again and look at the fluid level on the dipstick. The level should be the FULL COLD mark. at If necessary, add only enough fluid to bring the level up to the mark. What to Use To determine what kind fluid to use, see of "Recommended Fluids and Lubricants" in the Index. Always use the proper fluid. Failure to use the proper fluid can cause leaks and damage hoses and seals. 6-24