Tools Required

J 8089 Carbon Removing Brush

1. Clean the following components:

Caution: Wear safety glasses in order to avoid eye damage.

Important: Be careful not to scuff the chamber.

•	Use the J 8089 in order to remove the carbon from the combustion chambers.

•	Gasket surfaces

•	Refer to Replacing Engine Gaskets .

•	Valve stems and heads on a buffing wheel

•	Bolt hole threads. Remove all dirt, debris, or threadlocking material from the bolt holes.




2. Inspect the following:

2.1.	The cylinder head (1) for cracks in the exhaust ports and combustion chambers

2.2.	The cylinder head for external cracks in the water chambers

2.3.	The gasket surfaces for excessive scratches or gouging.

Refer to Replacing Engine Gaskets .

2.4.	The bolt hole threads for debris or damaged threads.

Refer to Thread Repair Specifications .

Tools Required

1. Inspect the valves for the following:

•	Burnt or eroded areas (1)

•	A worn margin (2)

•	A bent stem (3)

•	A worn or scored stem (4)

•	A worn key groove (5)

•	A worn stem tip (6)




2. Inspect the valve face for the following:

•	Worn or no margin (1,4)

•	Pitted surfaces (2)

•	Burnt or eroded areas (3)

3. Inspect the valve seats for a loose fit in the cylinder head.



4. Inspect the valve springs (4) for squareness.



5. Use the J 9666 in order to measure the valve spring tension.

Replace the spring if the spring tension is less than 310 N (70 lb) at 45.75 mm (1.80 in).




6. Measure the cylinder head for warpage with a straight edge and a feeler gauge.

•	A cylinder head deck with warpage in excess of 0.11 mm (0.004 in) within a 152.4 mm (6.0 in) area or 0.22 mm (0.008 in) overall area must be repaired or replaced.

•	A cylinder head exhaust manifold deck with warpage in excess of 0.22 mm (0.008 in) must be repaired or replaced.

•	A cylinder head intake manifold deck with warpage in excess of 0.22 mm (0.008 in) must be repaired or replaced.

•	Refer to Engine Mechanical Specifications .





Important: Excessive valve stem-to guide clearance may cause a noisy valve train, premature valve stem oil seal wear, component damage, and/or excessive engine oil consumption.

Insufficient valve stem-to-guide clearance will result in noisy or sticking valves. Valves that are too tight may disturb engine smoothness or lead to component damage.
7. Inspect for excessive valve stem (1) to guide (2) clearance.



8. Use a dial indicator and measure the valve stem-to-guide clearance.

8.1.	Install the valve into the guide.

8.2.	Install the J 8520 onto the cylinder head.

8.3.	Locate the dial indicator so that the movement of the valve stem from side to side (crosswise to the cylinder head) will cause a direct movement on the indicator stem.

8.4.	The indicator stem must contact the side of the valve stem just above the valve guide.

8.5.	Drop the valve head about 1.6 mm (0.0064 in) off the valve seat.

8.6.	Use light pressure and move the valve stem side to side in order to obtain a clearance reading.

8.7.	If the valve stem to guide clearance is in excess of 0.093 mm (0.0037 in), the valve must be replaced and/or the guide must be repaired to obtain the proper clearances.

Refer to Engine Mechanical Specifications .




9. If required, measure the valve guide for the proper installed height. Use a ruler and measure from the cylinder head valve spring machined surface to the top of the guide.

Refer to Engine Mechanical Specifications .