Disassembly and Assembly

Special Service Tools Required










DISASSEMBLY






1. Install the cylinder head on Head Holding Fixture 303-D040 (D83L-500-A) or equivalent.





2. Use Seal Remover 303-409 (T92C-6700-CH) to remove the camshaft oil seal. Discard the camshaft oil seal.





3. Remove the three camshaft end plate bolts, the fuel pump switch bracket and camshaft end plate.





4. Use Dial Indicator with Bracketry 100-002 (TOOL-4201-C) or equivalent, to inspect the camshaft end play.





The camshaft end play should be between 0.03-0.06 mm (0.0012-0.0024 inch).

NOTE:
- Inspect the camshaft end play prior to disassembling the cylinder head.
- Check the end play reading. This reading will be used during assembly to select an appropriate camshaft thrust plate.

5. Temporarily install the camshaft sprocket on the end of the camshaft.





6. Use Cam Sprocket Holding/Removing Tool 303-098 (T74P-6256-B) to hold the camshaft and remove the camshaft thrust plate bolt.
7. Remove the camshaft thrust plate.
8. Remove the camshaft sprocket.





9. Remove the camshaft from the front of the cylinder head.





10. Use Valve Spring Compressor Adapter Set 303-418 (T92P-6565-AH), Bar (part of 303-300 (T87C-6565-A)), and Valve Spring Compressor 303-104 (T74P-6565-A) to compress the valve springs, and remove the valve spring retainer keys with a magnet.
11. Release the valve spring compressor adapter set, bar, and valve spring compressor. Remove the valve spring retainer, valve spring, valve spring seat, and valve.





12. Use Impact Slide Hammer 100-001 (T50T-100-A) and Valve Stem Seal Remover 303-349 (T89P-6510-D) to remove the intake valve stem seal.
13. Use a pair of pliers to remove the exhaust valve stem seal.





14. Use Valve Guide Remover/Replacer 303-346 (T89P-6510-A) to drive the intake valve guides out of the cylinder head.





15. Use Valve Guide Remover/Replacer 303-298 (T87C-6510-A) to drive the exhaust valve guides out of the cylinder head.

ASSEMBLY
1. Refer to cylinder head cleaning and inspection procedures.
2. Position Intake/Exhaust Valve Guide Replacer 303-417 (T92P-6510-BH) on the exhaust valve guide.





3. Use Valve Guide Remover/Replacer 303-298 (T87C-6510-A) to drive the exhaust valve guides into the cylinder head.
4. Position Intake/Exhaust Valve Guide Replacer 303-417 (T92P-6510-BH) on the intake valve guide.





5. Use Valve Guide Remover/Replacer 303-346 (T89P-6510-A) to drive the intake valve guides into the cylinder head.





6. Measure from the lower valve spring seat to the top of the intake and exhaust valve guides. The measurement (L) should be 13.2-13.4 mm (0.520-0.528 inch).
7. Measure the valve stem-to-valve guide clearance. Ream the valve guide(s) as necessary.





8. Coat the intake valve stem seals with clean engine oil. Use Intake Valve Seal Replacer 303-416 (T92P-6510-AH) to drive the intake valve stem seal over the intake valve guide.





9. The intake valve stem seal should be 2.3 mm (0.091 inch) from the lower valve spring seat when fully installed.
10. Coat the exhaust valve stem seal with clean engine oil and install the exhaust valve stem seal by hand over the exhaust valve guide.
11. Install the lower valve spring seat.
12. Install the valve, valve spring, and valve spring retainer.





13. Use Valve Spring Compressor Adapter Set 303-418 (T92P-6565-AH), Bar (part of 303-300 (T87C-6565-A)), and Valve Spring Compressor 303-104 (T74P-6565-A) to compress the valve springs and install the valve spring retainer keys.
14. Tap the end of the valve stem lightly two or three times with a plastic hammer to verify that the valve spring retainer keys are fully seated.





15. Install the camshaft into the cylinder head.





16. Refer to the end play reading noted during disassembly to select an appropriate camshaft thrust plate.
The camshaft thrust plates in the illustration are stamped with identification marks. Refer to the chart in the illustration for the identification marks and thickness specifications for each camshaft thrust plate.





17. Install the appropriate camshaft thrust plate to bring the end play into specification.
18. Temporarily install the camshaft sprocket on the end of the camshaft.





19. Use Cam Sprocket Holding/Removing Tool 303-098 (T74P-6256-B) to hold the camshaft and install the camshaft thrust plate bolt. Tighten the camshaft thrust plate bolt to 78-88 Nm (58-65 ft. lbs.).
20. Remove the camshaft sprocket.





21. Position the camshaft end plate and fuel pump switch bracket and install the three camshaft end plate bolts.





22. Lubricate the sealing surfaces of a new camshaft front seal. Install the new camshaft front seal on Cam Seal Protector 303-365 (T9OP-6256-AH). Install the camshaft front seal on the front of the cylinder head using Camshaft Seal Replacer 303-414 (T92P-6256-AH).





23. Use Camshaft Seal Replacer 303-414 (T92P-6256-AH) to draw the camshaft oil seal into the cylinder head until the camshaft seal replacer bottoms out.
24. Remove the cylinder head from Head Holding Fixture 303-D040 (D83L-500-A) or equivalent.