10. IF NECESSARY, REPLACE VALVE GUIDE BUSHINGS (a) Insert an old valve wrapped with tape into the valve guide bushing and break off the valve guide bushing by hitting it with a hammer. NOTICE: Be careful not to damage the lifter hole. (b) Gradually heat the cylinder head to approx. 90°C (194°F). (c) Using SST and hammer, drive out valve guide bushing. SST 09201-70010 (d) Using a caliper gauge, measure the valve guide bore of the cylinder head. (e) Select a new valve guide bushing. If the valve guide bushing bore of the cylinder head is more than 11.027 mm (0.4341 in.), machine the bore to the following dimensions. Rebored valve guide bushing bore dimension: 11.050 — 11.077 mm (0.4350 — 0.4361 in.) Both intake and exhaust Bushing bore mm (in.) | Bushing size 11.000 — 11.027 (0.4331 — 0.4341) | Use STD Over 11.027 (0.4341) | Use O/S 0.05