LS7 Corvette Mechanical Repair Specs (PDF) - Bakes Online

Print Preview Version 8.0 PubTeX output 2006.06.15:1036 File: C:\DOCUME~1\PCOMPO~1.IGS\LOCALS~1\Temp\.aptcache\2006LS7/tfa01804.dvi User: PComposer Page: 1422006 Y Car GMX245 Corvette7.0L (LS7) Engine MechanicalIf the valve stem diameter is within specifications, and the stem-to-guide clearance is excessive, the cylinderhead must be replaced.Valve and Seat Grinding156174Important:• The titanium intake valves are not to be resurfaced.• Reconditioning the valve seats is very important. The seating of the valves must be perfect for the engine todeliver optimum power and performance. Several different types of equipment are available for grinding valve seats.• Another important factor is the cooling of the valve head. Good contact between the valve and the seat willensure that heat will be properly dissipated.• The recommendations of the equipment manufacturer should be followed carefully in order to obtain theproper results. Regardless of the type of equipment used, it is essential that valve guide bores be free from carbonor dirt to ensure proper centering of the tool pilot in the guide.• Exhaust valves that are pitted may be refaced to the proper angle. Valve stems that show excessive wear, orvalves that are warped excessively must be replaced. When an excessively warped exhaust valve head is refaced,a knife edge may be ground on part or all of the valve head, due to the amount of metal that must be removed.Knife edges lead to breakage, burning or pre-ignition due to heat localizing on this knife edge. If the edge of thevalve head is less than 1.25 mm (0.05 in) after grinding, replace the valve.• Several different types of equipment are available for refacing valves. The manufacturer recommendation ofthe equipment should be carefully followed in order to obtain the proper results.• DO NOT reface intake valves. Intake valves with excessive wear or damage MUST be replaced.1. Inspect the valve for the following conditions:• Burnt or eroded areas (1)• A worn margin (2)• A bent stem (3)• Awornorscoredstem(4)• A worn key groove (5)• Awornstemtip(6)142 of 272