Disassembly and Assembly

Components

Disassembly

CAUTION:
^ When installing sliding parts such as rocker arms, camshafts and oil seals, be sure to apply new engine oil on the sliding surfaces.
^ When tightening cylinder head bolts and rocker shaft bolts, apply new engine oil to thread portions and seat surfaces of bolts.
^ Do not disassemble hydraulic valve lifter.
^ Attach tans to the valve lifters so they are installed in their original positions.





^ If hydraulic valve lifter is kept on its side, there is a risk of air entering it. After removal, always set hydraulic valve lifter straight up, or when laying it on its side, have it soak in new engine oil.

VG33E:

1. Remove exhaust manifolds from cylinder head, loosen the bolts in the numerical order as shown.
2. Remove the rocker shafts with the rocker arms.
^ Loosen the bolts in two or three steps.





3. Remove the hydraulic valve lifters and lifter guide.
^ Hold the hydraulic valve lifters with wire so that they will not drop out of the lifter guide.

4. Remove the oil seal and camshaft.
^ Before removing the camshaft, measure the camshaft end play.





5. Remove the valve components using Tool as shown.





6. Remove the valve oil seals using Tool or suitable tool.

Inspection
CYLINDER HEAD DISTORTION





1. Measure the cylinder head sealing surface using a straight edge and a feeler gauge as shown. If the surface flatness is beyond the specified limit, resurface it or replace it as necessary.

NOTE: The resurfacing limit of the cylinder head is determined by the amount of cylinder block resurfacing necessary.

Head surface flatness: less than 0.1 mm (0.004 inch)
Resurfacing limit: Amount of cylinder head resurfacing is "A". Amount of cylinder block resurfacing is "B".
Maximum resurfacing limit (A + B): 0.2 mm (0.008 inch)
2. After resurfacing cylinder head, check the nominal cylinder head height is within specification. Check that the camshaft rotates freely by hand. If resistance is felt, the cylinder head must be replaced.
Nominal cylinder head height: 106.8 - 107.2 mm (4.205 - 4.220 inch)

CAMSHAFT VISUAL CHECK
Check camshaft for scratches, seizure and wear. Replace as necessary.

CAMSHAFT RUNOUT
1. Support the camshaft at the No. 2 and No. 4 camshaft journals.





2. Measure camshaft runout at the No. 3 journal as shown.
3. If the measured runout exceeds the limit, replace the camshaft.
Runout limit (total indicator reading): 0.1 mm (0.004 inch)

CAMSHAFT CAM HEIGHT





1. Measure the camshaft cam height as shown.
Standard cam height for intake and exhaust: 38.943 - 39.133 mm (1.5332 - 1.5407 inch)
Cam wear limit: 0.15 mm (0.0059 inch)
2. If the measured wear is beyond the limit, replace the camshaft.

CAMSHAFT JOURNAL CLEARANCE





1. Measure the outer diameter of the camshaft journal.
Standard outer camshaft journal diameter
A: 46.920 - 46.940 mm (1.8472 - 1.8480 inch)
B: 42.420 - 42.440 mm (1.6701 - 1.6709 inch)
C: 47.920 - 47.940 mm (1.8866 - 1.8874 inch)





2. Measure the inner diameter of the camshaft bearing for the corresponding camshaft journal positions measured in step 1.
Standard inner camshaft bearing diameter
A: 47.000 - 47.025 mm (1.8504 - 1.8514 inch)
B: 42.500 - 42.525 mm (1.6732 - 1.6742 inch)
C: 48.000 - 48.025 mm (1.8898 - 1.8907 inch)
3. The camshaft journal is the difference between the outer diameter of the camshaft journal and the inner diameter of the camshaft bearing. If the clearance exceeds the limit, replace camshaft and/or cylinder head.
Camshaft journal clearance limit: 0.15 mm (0.0059 inch)

CAMSHAFT END PLAY
1. Install the camshaft and the locate plate in the cylinder head.





2. Measure the camshaft end play.
Standard camshaft end play: 0.03 - 0.06 mm (0.0012 - 0.0024 inch)





3. If it is out of the specified range, select thickness of camshaft locate plate to obtain standard specified end play.
Example:
When camshaft end play is 0.08 mm (0.0031 inch) with camshaft locate plate 1 replace camshaft locate plate 1 with camshaft locate plate 4 to set the end play at 0.04 mm (0.0016 inch).

CAMSHAFT SPROCKET RUNOUT
1. Support the camshaft at the No. 2 and No. 4 camshaft journals.
2. Install the sprocket on the camshaft.





3. Measure the camshaft sprocket runout.
Runout limit (total indicator reading): 0.1 mm (0.004 inch)
4. If the runout exceeds the limit, replace the camshaft sprocket.

VALVE GUIDE CLEARANCE





1. Measure the valve deflection at a right-angled direction to the camshaft. The valve and valve guide mostly wear in that direction.
Valve deflection limit (dial gauge reading): 0.20 mm (0.0079 inch)
2. If the valve guide deflection exceeds the limit, check the valve to valve guide clearance.





a. Measure valve stem diameter and valve guide inner diameter as shown.
b. Check that the valve to valve guide clearance is within specification.
Valve to valve guide clearance
Intake: 0.020 - 0.053 mm (0.0008 - 0.0021 inch)
Exhaust: 0.030 - 0.049 mm (0.0012 - 0.0019 inch)
Limit: 0.10 mm (0.0039 inch)
c. If the valve to valve guide clearance exceeds the limit, replace the valve or valve guide as necessary.

VALVE GUIDE REPLACEMENT





1. To remove the valve guide, heat cylinder head to 150° - 160°C (302° - 320°F) by soaking it in heated oil.





2. Drive out the valve guide using a press with a pressure limited to under 20 kN (2 ton, 2.2 US ton, 2.0 Imp ton) of pressure, or a hammer and suitable tool.





3. Ream out the cylinder head valve guide hole to specification for the service valve guide part as shown.
Valve guide hole diameter (for service parts)
Intake: 11.175 - 11.196 mm (0.4400 - 0.4408 inch)
Exhaust: 12.175- 12.196 mm (0.4793 - 0.4802 inch)





4. Heat the cylinder head to 150° - 160°C (302° - 320°F) in heated oil and press the service valve guide into the cylinder head to the specified height as shown.
Height "L": 13.2 - 13.4 mm (0.520 - 0.528 inch)





5. Ream out the new service valve guide in the cylinder head to the specified diameter.
Valve guide finished inner diameter
Intake: 7.000 - 7.018 mm (0.2756 - 0.2763 inch)
Exhaust: 8.000 - 8.011 mm (0.3150 - 0.3154 inch)

VALVE SEATS





Check the valve seats for any pitting at the valve contact surface, and re-surface or replace the valve seat if it has worn out.
^ Before repairing the valve seats, check the valve and valve guide for wear.
^ Use both hands to cut the valve seat uniformly.

REPLACING VALVE SEAT FOR SERVICE PARTS
1. Bore out the old seat until it collapses. The machine depth stop should be set so that the boring cannot continue beyond the bottom of the face of the valve seat recess in the cylinder head.
2. Ream out the cylinder head recess.

CAUTION: Reaming should be done in circles concentric to the valve guide center so that valve seat will have the correct fit.





Reaming bore for service valve seat
Oversize: 0.5 mm (0.020 inch)
Intake: 44.500 - 44.516 mm (1.7520 -1.7526 inch)
Exhaust: 37.500 - 37.516 mm (1.4764 -1.4770 inch)





3. Heat the cylinder head to 150° - 1 60°C (302° - 320°F) by soaking it in heated oil.





4. Press fit the valve seat into the cylinder head until it seats on the bottom of the valve seat bore.
5. Cut or grind the valve seat using a suitable tool to specification.





6. After cutting, lap the valve seat with an abrasive compound.
7. Check the valve seating dimensions.





8. Use a depth gauge to measure the distance "L".between the mounting surface of the cylinder head spring seat and the valve stem end as shown.
Intake: 44.7 - 44.9 mm (1.760 - 1.768 inch)
Exhaust: 45.4 - 45.6 mm (1.787 - 1.795 inch)
^ If the distance "L" as shown is shorter than specified, repeat step 5 above to adjust it.
^ If the distance "L" as shown, is longer and the valve stem tip cannot be ground within the specified limit to obtain the specified distance "L", then replace the valve seat with a new one.
Valve stem tip grinding allowance: 0.2 mm (0.008 inch) or less

VALVE DIMENSIONS
1. Check the dimensions of each valve.





2. When the valve head has been worn to less then 0.5 mm (0.020 inch) in margin thickness "T", replace the valve.

VALVE SPRING
Squareness





1. Measure the "S".dimension of the valve spring against a right angle tool for out-of-square as shown.
Out-of-square: less than 2.0 mm (0.079 inch)
2. If the valve spring out-of-square exceeds the limit, replace the valve spring.

Pressure





1. Check the valve spring pressure at the specified valve open height OR shown
Standard pressure with valve open: 523.7 N (53.4 kg,117.7 lbs.) at 30.0 mm (1.181 inch)
Limit pressure with valve open: 733 N (74.8 kg, 164.8 lbs.) at 30 mm (1.181 inch)
2. If not within specification, replace the valve spring.

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





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





3. Check the inner diameter of the rocker arm.
Rocker arm inner 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)

CAUTION: Keep the rocker arm with the hydraulic valve lifter standing upright to prevent air from entering the hydraulic valve lifter when checking.

HYDRAULIC VALVE LIFTER





1. Check the contact and sliding surfaces for wear or scratches.
2. Check the outer diameter of the valve lifter.
Valve lifter outer diameter: 15.947 - 15.957 mm (0.6278 - 0.6282 inch)





3. Check the valve lifter guide inner diameter.
Valve lifter guide 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 the valve component parts.
^ Always use a new valve oil seal.
^ Install the valve spring (uneven pitch type) with the 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 the camshafts, locate plates, and cylinder head rear covers.
^ Position the knock pin of the camshaft at the top as shown.





3. Install the valve lifters and the valve guide.
^ Assemble the valve lifters in their original position and hold all of the valve lifters with wire to prevent the lifters from falling out of the guide.
^ Remove the wire after installing the lifters and guide.





4. Install the rocker shafts with the rocker arms.
^ Tighten the bolts gradually in two or three stages to specification in the following camshaft positions:
^ Before tightening the bolts, the camshaft must be positioned where the lobe is not contacting the lifter.

a. Set No. 1 piston at TDC on the compression stroke and tighten the rocker shaft bolts for No. 2, No. 4 and No. 6 cylinders.
b. Set No. 4 piston at TDC on the compression stroke and tighten the rocker shaft bolts for No. 1, No. 3 and No. 5 cylinders.