6. CYLINDER HEAD/VALVES STRYKER 125/150 Ream the guides to remove any carbon build-up using a valve guide reamer. Special Tool Valve Guide Reamer During this operation, rotate the reamer clockwise and do not insert or remove it straight when it is stopped. Valve Guide Reamer Measure each valve guide I.D. Service Limits: IN: 5.780mm replace if over EX: 5.780mm replace if over Subtract each valve stem O.D. from the corresponding guide I.D. to obtain the stem-to-guide clearance. Service Limits: IN: 0.080mm EX: 0.10mm · If the stem-to-guide clearance exceeds the service limits, replace the guides. · Reface the valve seats whenever the valve guides are replaced. VALVE GUIDE REPLACEMENT Drive out the old valve guides with the valve guide driver. · Remove carbon build-up from the guides before driving them out. · Drive the guides out vertically. Special Tool Valve Guide Driver Valve Guide Driver 6-10