For 1990-2009 cars only
Valve Guide Reaming Procedure for Oversized Valve Stems
- Ream the valve guide, as necessary, in order to achieve proper valve stem-to-guide clearance with the new, oversized valve stems.
- Always recondition the valve seat after reaming the valve guide bores or installing new valves.
- Replace the cylinder head if the valve guide cannot be repaired or reamed to accept an oversize valve stem.
Valve Reconditioning Procedure
- Replace the valve if the valve stem shows excessive wear or is warped.
- Reface pitted valves on a valve refacing machine in order to ensure the correct relationship between the head and the stem.
- Replace the valve if the edge of the head is less than 0.79 mm (0.031 in) thick after grinding.
Important: Several different types of equipment are available for reconditioning valves. Use the equipment the manufacturer recommendations in order to attain the proper results.
Valve Seat Reconditioning Procedure
- Recondition the valve seats.
- The valves must seat perfectly for the engine to deliver optimum power and performance.
- Correct contact (1) between each valve and valve seat in the cylinder head is essential in order to ensure the heat in the valve head is properly carried away.
- The valve seats should be concentric to within 0.050 mm (0.002 in) total indicator runout.
Important:
• Several different types of equipment are available for reconditioning valve seats. Use the equipment the manufacturer recommendations in order to attain the proper results. • Always recondition the valve seat after reaming the valve guide bores or installing new valves.
Important: Regardless of the type of equipment used, it is essential the valve guide bores are free from carbon and dirt, in order to ensure the proper centering of the pilot in the guide.
