COMPRESSION Valves & Guides TABLE NO.  2 VALVE TAPPET CLEARANCE MODEL SERIES INTAKE EXHAUST ALUMINUM MAX. MIN. MAX. MIN. CYLINDER Milli- Milli- Milli- Milli- Inches meter Inches meter Inches meter Inches meter 6B, 60000, 8B, 80000, 82000, 92000, 94000, 100000, 110000, 130000, .007 0.18 .005 0.13 .011 0.28 .009 0.23 140000, 170000, 190000, 220000, 250000 Milli- Milli- Milli- Milli- CAST IRON CYLINDER Inches meter Inches meter Inches meter Inches meter 5, 6, 8, N, 9, 14, 19, .009 0.23 .007 0.18 .016 0.41 .014 0.36 190000, 200000 23, 230000, 240000, .009 0.23 .007 0.18 .019 0.48 .017 0.43 300000, 320000 To Reface Valves and Seats Faces on valves and valve seats should be resurfaced with a valve grinder or cutter, to an angle of 45°.  NOTE: SOME ENGINE MODELS HAVE A 300 INTAKE VALVE AND SEAT.  Valve and seat should then be lapped with a fine lapping compound to remove grinding marks and assure a good seat.  Valve seat width should be 3/64" to 1/16" (1.19-1.58 mm).  Fig. 7. If the seat is wider, a narrowing stone or cutter should be used.  If either the seat or valve is badly burned, it should be replaced. Replace valve if margin is 1/64" (0.4 mm) or less after refacing.  Fig.  7. Fig.  7 -- Valve and Seat Dimensions To Check and Adjust Tappet Clearance Insert the valves in their respective positions in the cylinder.  Turn the crankshaft to top dead center, end of compression stroke.  Both valves are now closed.  Then check clearance on the intake and exhaust valves with feeler gauge.  See Table 2.  Grind off the end of the valve stem if necessary, to obtain proper clearance. CAUTION: Piston MUST be at top dead center at the end of compression stroke to assure both valves being closed. NOTE: Check clearance cold. To Install Valves Some engines use the same spring for intake and exhaust side, while others use a heavier spring on the exhaust side.  Compare springs before installing. If retainers are held by a pin or collars, Fig. 2, Illus. 1 and 2, place valve spring and retainer (and cup on Model Series 9, 14, 19, 20, 23, 24 and 32) into valve spring compressor 19063.  Compress the spring until it is solid. insert the compressed spring and retainer (and cup when used) into the valve chamber.  Then drop the valve into place, pushing the stem through the retainer.  Hold the spring up in the chamber, and the valve down. insert the retainer pin with a needle nose pliers or place the collars in the groove in the valve stem.  Lower the spring until the retainer fits around the pins or collars, then pull out the spring compressor.  Fig.  3.  Be sure pin or collars are in place. If self-lock retainer, Fig. 2, Illus. 3, is used, compress retainer and spring with compressor 19063.  Large diameter of retainer should be toward front of valve chamber.  Fig. 8.  Insert compressed spring and retainer into valve chamber.  Drop the valve stem through larger area of retainer slot and move the compressor so as to center the small area of the valve retainer slot onto the valve stem shoulder.  Release the spring tension and remove the compressor. 3