52 SENR9977 Testing and Adjusting Section i01905914 Cylinder Head - Inspect Refer to Specifications, “Cylinder Head” for the requirements of flatness. Remachining the Cylinder Head 1. Remove the cylinder head from the engine. The bottom face of cylinder head can be resurfaced if any of the following conditions exist: 2. Remove the water temperature regulator housing. 3. Inspect the cylinder head for signs of gas or coolant leakage. The bottom face of the cylinder head is not flat within the specifications. The bottom face of the cylinder head is damaged by pitting, corrosion, or wear. 4. Remove the valve springs and valves. 5. Clean the bottom face of the cylinder head thoroughly.
Clean the coolant passages and the lubricating oil passages. Make sure that the contact surfaces of the cylinder head and the cylinder block are clean, smooth and flat. Note: The thickness of the cylinder head must not be less than 117.20 mm (4.614 inch) after the cylinder head has been machined. If the bottom face of the cylinder head has been remachined, the recesses in the cylinder head for the valve seat inserts must be machined. The valve seat inserts must be ground on the side which is inserted into the cylinder head. Grinding this surface will ensure that no protrusion exists above the bottom face of the cylinder head.
Refer to Specifications, “Cylinder Head Valves” for the correct dimensions. 6. Inspect the bottom face of the cylinder head for pitting, corrosion, and cracks. Inspect the area around the valve seat inserts and the holes for the fuel injectors carefully. 7. Test the cylinder head for leaks at a pressure of 200 kPa (29 psi). i01889496 Piston Height - Inspect Table 5 g01012606 Illustration 58 Flatness of the cylinder head (typical example) If the height of the piston above the cylinder block is not within the tolerance that is given in the Specifications Module, “Piston and Rings”, the bearing for the piston pin must be checked. Refer to Testing and Adjusting, “Connecting Rod - Inspect”.
If any of the following components are replaced or remachined, the piston height above the cylinder block must be measured: (A) Side to side (B) End to end (C) Diagonal 8. Measure the cylinder head for flatness. Measure the flatness of the cylinder head with a straight edge and with a feeler gauge. Measure the cylinder head from one side to the opposite side (A). Crankshaft Cylinder head Measure the cylinder head from one end to the opposite end (B). Measure the cylinder head from one corner to the opposite corner (C). Connecting rod Bearing for the piston pin Required Tools Part Number Part Description Qty 21825617 Dial gauge 1 21825496 Dial gauge holder 1