Cylinder Head Assembly: Testing and Inspection
1. Clean all parts, being sure to remove all gasket fragments, dirt, oil or grease, carbon, moisture residue, and other foreign materials.
2. Inspection and repairs must be performed in the order specified.
CYLINDER HEAD
1. Inspect the cylinder head for damage, cracks, and water or oil leakage. Replace the cylinder head if necessary.
2. Measure the cylinder head distortion in the six directions shown in the figure.
Distortion:
B6: O.15mm {O.006 in} max.
BP: O.1mm {O.004 in} max.
3. Inspect for the following and repair or replace.
(1) Sunken valve seats
(2) Damaged intake and exhaust manifold contact surfaces
(3) Excess camshaft oil clearances and end play
4. If the cylinder head distortion exceeds specification, grind the cylinder head surface.
5. If the cylinder head height is not within specification, replace it.
Height: 107.4-107.6mm {4.229-4.236 in}
Grinding B6: 0.2Omm {0.008 in} max.
BP: 0.1Omm {0.004 in} max.
6. Measure the manifold contact surface distortion in the six directions shown in the figure.
Distortion: O.15mm {O.006 in} max.
7. If distortion exceeds specification, grind the surface or replace the cylinder head.
VALVE MECHANISM
Valve and Valve Guide
1. Inspect each valve for the following. Replace or resurface the valve if necessary.
(1) Damaged or bent stem
(2) Rough or damaged face
(3) Damaged or unevenly worn stem tip
2. Measure the valve head margin thickness of each valve. Replace the valve if necessary.
Margin thickness min.
3. Measure the length of each valve
Length
4. Measure the stem diameter of each valve at the points shown.
Diameter
Inner diameter
5. Measure the inner diameter of each valve guide at the points shown.
6. Calculate the valve stem-to-guide clearance. Subtract the outer diameter of the valve stem from the inner diameter of the corresponding valve guide.
Clearance
IN: O.025-O.06Omm {0.OO1O-O.0023 in}
EX: O.030-O.065mm {O.0012-0.0025 in}
Maximum: O.2Omm {O.OO8 in}
7. If the clearance exceeds specification, replace the valve and/or valve guide.
8. Measure the protrusion height"A"of each valve guide. Replace the valve guide if necessary.
Height
Replacement of valve guide
Note
^ The intake and exhaust valve guides are different. Use the correct valve guide.
Removal
Remove the valve guide from the side opposite the combustion chamber with the SST.
Installation
1. Assemble the SST so that depth L is as specified.
Depth L
2. Tighten the nut.
3. Tap the valve guide in from the side opposite the combustion chamber until the SST contacts the cylinder head.
4. Verify that the valve guide height is within specification.
5. If not repeat steps 1-4.
Valve Seat
1. Inspect the contact surface of each valve seat and valve face for the following:
(1) Roughness
(2) Damage
2. If necessary, resurface the valve seat with a 45° valve seat cutter and/or resurface the valve face.
3. Apply a thin coat of Prussian blue to the valve face.
4. Inspect the valve seating by pressing the valve against the seat.
(1) If blue does not appear 360° around the valve face, replace the valve.
(2) If blue does not appear 360° around the valve seat, resurface the seat.
5. Measure the seat contact width.
width
6. Verify that the valve seating position is at the center of the valve face.
B6 (FEDERAL, CANADA)
(1) If the seating position is too high, correct the valve seat with a 75° (IN) or 7O° (EX) cutter and a 45° cutter.
(2) If the seating position is too low, correct the valve seat with a 35° (IN) or 15° (EX) cutter and a 45° cutter.
B6 (CALIFORNIA), BP
(1) If the seating position is too high, correct the valve seat with a 7O° cutter and a 45 cutter.
(2) If the seating position is too low, correct the valve seat with a O° cutter and a 45° cutter.
7. Seat the valve to the valve seat with lapping compound.
8. inspect the sinking of the valve seat.
Measure the protruding length (dimension L) of the valve stem.
Demension L
B6 (CALIFORNIA),
IN: 42.5mm {l.673 in}
EX: 41.5mm {1.634 in}
BP
IN: 42.5mm {l.673 in}
EX: 41.Omm {1.614 in}
Valve Spring
1. Inspect each valve spring for cracks or damage.
2. Measure the free length and out-of-square. Replace the valve spring if necessary.
Free length
Out-of-square max.
Camshaft
1. Set the front and rear journals on V-blocks.
2. Measure the camshaft runout. replace the camshaft if necessary.
Height
3. Inspect the camshaft for wear or damage. Replace the camshaft if necessary.
4. Measure the cam lobe heights at the two points as shown.
Height
5. Measure the journal diameter in X and Y directions at the two points (A and B) shown.
Diameter
Out-of-round: 0.05 {0.002} max.
6. Measure the oil clearance between the camshaft and cylinder head.
(1) Remove all foreign material and oil from the journals and the camshaft bore.
(2) Measure the camshaft bore diameter.
Diameter
(3) Subtract the journal diameter from the bore diameter.
Oil clearance
(4) If the clearance exceeds the maximum, replace the camshaft or cylinder head.
7. Measure the camshaft end play. If it exceeds the maximum, replace the thrust plate or camshaft.
End play
B6 (FEDERAL, CANADA):
O.05-O.18mm {O.O02O-O.OO7O in }
B6 (CALIFORNIA), BP:
O.06-O.19mm {0.OO24-O.OO74 in}
Maximum: O.20mm (0.008 in}
Rocker Arm and Rocker Arm Shaft
1. Check for wear or damage to the contact surface of the rocker arm shaft or the rocker arm. Replace if necessary.
2. Check the oil clearance between the rocker arm and shaft. Replace if necessary.
(1) Measure the rocker arm inner diameter.
Diameter
(2) Measure the rocker arm shaft diameter.
Diameter
(3) Subtract the shaft diameter from the inner diameter
Oil clearance
HLA
Check the HLA face for wear or damage and replace it necessary.
Caution
^ To prevent damaging the 0-ring, do not remove the HLA unless necessary.
CYLINDER BLOCK
1. Check the cylinder block for the following and repair or replace the cylinder block as necessary.
(1) Leakage damage
(2) Cracks
(3) Scoring of wall
2. Measure the distortion of the top surface of the cylinder block in the six directions shown in figure.
Distortion: O.l5mm {O.006 in} max.
3. If the distortion exceeds the maximum, repair by grinding or replace the cylinder block.
Height
Grinding: O.2Omm {O.008 in} max.