1. Remove the valve cover following the procedure in the Engine Service Manual.
2. Pressurize the cooling system to 96 kPa (14 psi)
3. Inspect the entire cylinder head for cracks or leaks at the cup plugs.
• If a leak is noticed, repair or replace.
• If no leaks are noticed, do step 4.
4. Drain coolant from system.
5. Remove cylinder head from engine following the procedures in the Engine Service Manual.
6. Inspect and pressure test the cylinder head following the procedures in the Engine Service Manual.
• Inspect cylinder head gasket for damage at sealing points that may have caused a leak. Verify crankcase and cylinder head surface flatness using a straightedge and feeler gauge. Replace the head gasket. Repair or replace the cylinder head if necessary.
• Inspect the cylinder head for cracks in the coolant passages. Repair or replace.
7. If cylinder head is in good condition, remove cylinder sleeve crevice seals following the procedures in the Engine Service Manual.
• Inspect the engine block for cracks in the coolant passages. Repair or replace.
• Inspect for damaged cylinder liners and seals. Repair or replace.
8. Test the cooling system again after any repair to validate the repair.
