90081A 1 Mercruiser PULLEY

Engine Valve Lash
Adjust
To prevent possible injury, do not use the starter motor to turn the flywheel.Hot engine components can cause burns. Allow additional time for the engine to cool before measuring valve clearance.
Measure the valve lash with the engine stopped. To obtain an accurate measurement, allow at least 20 minutes for the valves to cool to engine cylinder head and block temperature.
Adjust the valve clearance to within 0.08 mm (.003 in) of the nominal clearance.See "Engine Valve Rotators" before installing valve cover. Refer to the Service Manual or your Caterpillar dealer for the complete valve adjustment procedure.Engine Valve Rotators
Observe Rotation of Valves With Engine Idling After Setting the Valve Clearances
When inspecting the valve rotators, protective glasses or face shield and protective clothing must be worn, to prevent being burned by hot oil spray.
After setting all valve clearances and before installing the valve cover:1. Start the engine.2. Move the governor control to LOW IDLE position. 3. Watch the top surface on each valve rotator. Each valve rotator should turn slightly each time the valve closes.If a valve fails to rotate, contact your Caterpillar dealer.Every 3000 Service Hours or 2 Years
You must read and understand the warnings and instructions contained in the Safety section of this manual before performing any operation or maintenance procedures.Cooling System Coolant
Change Coolant/Clean System
Do not change the coolant until you read and understand the material in the "Cooling System Specifications" section.
Drain the coolant earlier whenever the coolant is dirty or foaming is observed. The radiator cap is located in the top of the hood. 1. Remove the radiator cap slowly to relieve pressure. 2. Open the drain valve and allow the coolant to drain. Drain valve is located under the radiator.3. Close the drain valve. Fill the system with clean water and a 6 to 10% concentration of cooling system cleaner.4. Start and run the engine for 90 minutes. Stop the engine and drain the cleaning solution.5. Flush the system with water, with the engine stopped, until the draining water is clear.6. Close the drain valve.7. Add the coolant solution. See "Cooling System Specifications" and "Lubricant Viscosities and Refill Capacities." Do not add supplemental coolant additive or change element at this time, unless you are not using Caterpillar Antifreeze which contains additive.8. Start the engine and operate it with the radiator cap off, until the thermostat opens and the level stabilizes.9. Maintain the coolant level to within 1 cm (1/2 in) of the bottom of the fill pipe.10. Install the cap.11. Stop the engine.Clean the Cooling System Relief Valve
Clean or replace the relief valve if the system overheats or loss of coolant is observed.1. Remove the radiator cap slowly to relieve pressure. 2. Remove the bolts from the valve and remove the valve assembly. 3. Inspect valve (1), valve seals (2) and gasket (3). Replace if necessary.4. Inspect valve cover (4) and mounting bolts (5).5. Install the relief valve assembly.6. Check the coolant level. Maintain the coolant level to within 1 cm (1/2 in) of the bottom of the fill pipe.7. Install the radiator cap.Clean Outside of Radiator Fins
Compressed air is preferred, but high pressure water or steam can be used to remove dust, leaves and general debris from radiator fins.