Engine Mechanical (SOHC): Overhaul Subaru Forester SG

DISASSEMBLY

1. Remove the bolts which secure rocker shaft.
2. Extract the rocker shaft. Remove the valve rocker arms, springs and shaft supports from rocker shaft. NOTE: Arrange all removed parts in order so that they can be installed in their original positions.
3. Remove the nut and adjuster screw from valve rocker.

ASSEMBLY

1. Install the adjuster screw and nut to valve rocker.
2. Arrange the valve rocker arms, springs and shaft supports in assembly order and insert valve rocker shaft. Tightening torque (Shaft supports installing bolts): 5 N.m (0.5 kgf-m, 3.6 ft-lb) NOTE: Valve rocker arms, rocker shaft and shaft supports have identification marks. Ensure the parts with same markings are properly assembled.
3. Install the valve rocker shaft securing bolts.

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1. Measure the inside diameter of valve rocker arm and outside diameter of valve rocker shaft, and determine the difference between the two (= oil clearance). Clearance between arm and shaft: Standard 0.020 - 0.054 mm (0.0008 - 0.0021 in) Limit 0.10 mm (0.0039 in)
2. If oil clearance exceeds the limit, replace the valve rocker arm or shaft, whichever shows greater amount of wear. Rocker arm inside diameter: 22.020 - 22.041 mm (0.8669 - 0.8678 in) Rocker shaft diameter: 21.987 - 22.000 mm (0.8656 - 0.8661 in)
3. If cam or valve contact surface of valve rocker arm is worn or dented excessively, replace the valve rocker arm.
4. Check that the valve rocker arm roller rotates smoothly. If not, replace the valve rocker arm.

1. Place the cylinder head on ST. ST 498267800 CYLINDER HEAD TABLE
2. Set the ST on valve spring. Compress the valve spring, and then remove the valve spring retainer key. Remove each valve and valve spring. ST 499718000 VALVE SPRING REMOVER

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1. Installation of valve spring and valve Place the cylinder head on ST. ST 498267800 CYLINDER HEAD TABLE Coat the stem of each valve with engine oil and insert valve into valve guide. NOTE: When inserting the valve into valve guide, use special care not to damage the oil seal lip. Install the valve spring and retainer. NOTE: Be sure to install the valve springs with their close-coiled end facing the seat on the cylinder head. Set the ST on valve spring ST 499718000 VALVE SPRING REMOVER Compress the valve spring, and then fit the valve spring retainer key. After installing, tap the valve spring retainers lightly with plastic hammer for better seating.

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1. Check the valve springs for damage, free length, and tension. Replace the valve spring if it is not to the specifications presented below.
2. To measure the squareness of valve spring, stand the spring on a surface plate and measure its deflection at the top using a try square.