GS300 & SC300
- Drain cooling system. Remove air intake pipe for access to intake air connector with throttle body. See Fig 1. Disconnect necessary electrical connectors, control cables, hoses and engine wire clamps for removal of intake air connector with throttle body.
- Note location of throttle body bracket. See Fig 1. Remove throttle body bracket-to-cylinder head nuts. Remove intake air connector-to-air intake chamber bolts/nuts. Remove air intake connector with throttle body and gasket from air intake chamber.
- Remove oil filler cap. Remove bolts and upper timing belt cover with gasket. Upper timing belt cover is located above timing belt. Disconnect electrical connectors from ignition coils, located above the spark plugs, in between the valve covers. Remove bolts and ignition coils with spark plug wires. Remove spark plugs.
- Disconnect engine wiring harness for access to valve covers. Remove bolts/nuts, valve covers and gaskets.
- Rotate crankshaft pulley clockwise so crankshaft pulley timing mark (groove) aligns with "0" mark on timing belt cover and cylinder No. 1 (front cylinder) is at TDC on compression stroke. Ensure timing marks on camshaft sprockets are aligned with timing marks on timing belt cover. See Fig 2. If timing marks are not aligned, rotate crankshaft pulley clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover.
- Using feeler gauge, measure and record valve clearance of intake valves on cylinders No. 1, 2 and 4, and exhaust valves on cylinders No. 1, 3 and 5. Perform STEP 1. See Fig 3.
- Rotate crankshaft pulley clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover. Using feeler gauge, measure and record valve clearance of intake valves on cylinders No. 3, 5 and 6, and exhaust valves on cylinders No. 2, 4 and 6. Perform STEP 2. See Fig 3.
- Ensure valve clearance is within specification. See VALVE CLEARANCE SPECIFICATIONS (GS300 & SC300) table.VALVE CLEARANCE SPECIFICATIONS (GS300 & SC300)
Application (1) In. (mm) Intake .006-.010 (.15-.25) Exhaust .010-.014 (.25-.35) (1) Adjust valve clearance with engine cold. - If valve clearance adjustment is required, rotate crankshaft pulley so camshaft lobe is facing upward on valve to be adjusted. Rotate valve lifter so notch area on valve lifter is at 90-degree angle to camshaft. This will place notch area perpendicular to camshaft.
- Valve Clearance Adjuster (SST 09248-55040) is used for adjusting valve clearance. Press valve lifter downward using SST "A" of valve clearance adjuster. See Fig 4. Install SST "B" between camshaft and valve lifter with side marked with No. 7 or No. 9 at designated position. See Fig 4. Remove SST "A".NOTE: When adjusting valve clearance on intake valve on cylinder No. 1, it may be necessary to remove No. 2 camshaft bearing cap so SST "B" may be installed between camshaft and valve lifter.
- Using small screwdriver and magnet, remove adjusting shim. Using micrometer, measure thickness of removed adjusting shim. Using measured clearance and adjusting shim thickness, determine correct thickness of adjusting shim to be used. See Figure and Figure .
- Install proper adjusting shim with imprinted numbers on adjusting shim facing downward, toward valve lifter. Using SST "A", press downward on valve lifter and remove SST "B". Recheck valve clearance.
- Install No. 2 camshaft bearing cap if removed. Tighten camshaft bearing cap bolts to specification. See TORQUE SPECIFICATIONS .
- To install remaining components, reverse removal procedure using NEW gasket for air intake connector. Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. See. Fig 5. Tighten bolts/nuts to specification. See TORQUE SPECIFICATIONS . Fill cooling system.