Hydraulic Valve Lifter - Diameter

VALVE DIMENSIONS





Check dimensions in each valve. When valve head has been worn down to 0.5 mm (0.020 inch) in margin thickness, replace valve.
Grinding allowance for valve stem tip is 0.2 mm (0.008 inch) or less.

VALVE SPRING
Squareness





1. Measure "S" dimension. Out-of-square:
Outer: Less than 2.2 mm (0.087 inch)
Inner: Less than 1.9 mm (0.075 inch)
2. If it exceeds the limit, replace spring.





Pressure
Check valve spring pressure.
Standard pressure:
Outer: 523.7 N (53.4 kg, 117.7 lb.) at 30.0 mm (1.181 inch)
Inner: 255.0 N (26.0 kg, 57.3 lb.) at 25.0 mm (0.984 inch)
Limit pressure:
Outer: More than 228.5 N (23.3 kg, 51.4 lb.) at 25.0 mm (0.984 inch)
Inner: More than 225.6 N (23.0 kg, 50.7 lb.) at 25.0 mm (0.984 inch)
If not within specification, replace spring.

ROCKER SHAFT AND ROCKER ARM
1. Check rocker shafts for scratches, seizure and wear.





2. Check outer diameter of rocker shaft.
Diameter: 17.979 - 18.000 mm (0.7078 - 0.7087 inch)





3. Check inner diameter of rocker arm.
Diameter: 18.007 - 18.028 mm (0.7089 - 0.7098 inch)
Rocker arm to shaft clearance: 0.007 - 0.049 mm (0.0003 - 0.0019 inch)
- Keep rocker arm with hydraulic valve lifter standing to prevent air from entering hydraulic valve lifter when checking.

HYDRAULIC VALVE LIFTER
1. Check contact and sliding surfaces for wear or scratches.





2. Check diameter of valve lifter.
Outer diameter: 15.947 - 15.957 mm (0.6278 - 0.6282 inch)





3. Check valve lifter guide inner diameter.
Inner diameter: 16.000 - 16.013 mm (0.6299 - 0.6304 inch)
Standard clearance between valve lifter and lifter guide: 0.043 - 0.066 mm (0.0017 - 0.0026 inch)

Assembly
1. Install valve component parts.
- Always use new valve oil seal.
- Before installing valve oil seal, install inner valve spring seat.





- Install outer valve spring (uneven pitch type) with its narrow pitch side toward cylinder head side.
- After installing valve component parts, use plastic hammer to lightly tap valve stem tip to assure a proper fit.





2. Install camshafts, locate plates and cylinder head rear covers.
- Set knock pin of camshaft at the top.





3. Install valve lifters into valve lifter guide.
- Assemble valve lifters to their original position and hold all valve lifters with wire to prevent lifters from falling off.
- After installing, remove the wire.





4. Install rocker shafts with rocker arms.
- Tighten bolts gradually in two or three stages.
- Before tightening, be sure to set camshaft the lobe at the position where lobe is not lifted.
a. Set No. 1 piston at TDC on its compression stroke and tighten rocker shaft bolts for No. 2, No. 4 and No. 6 cylinders.
b. Set No. 4 piston at TDC on its compression stroke and tighten rocker shaft bolts for No. 1, No. 3 and No. 5 cylinders.
5. Install exhaust manifold to cylinder head in reverse order of removal.