105401-0590 ZEXEL 9 420 612 821 BOSCH GOVERNOR 9420612821 1054010590 1910990312

Guidelines For Reusable Parts; Valves And Valve Springs, Forms SEBF8002 and SEBF8034 have the procedure and specifications necessary for checking used valves and valve springs.(1) Springs (Inner And Outer):Inner Valve Spring (4W2472): Assembled length ... 50.24 mm (1.978 in)Load at assembled length ... 178 18 N (40.1 4.1 lb)Operating length (min) ... 35.97 mm (1.416 in)Load at min operating length ... 343 17 N (77.2 3.8 lb)Free length after test ... 65.7 mm (2.60 in)Outside diameter ... 25.13 mm (.989 in)Outer Valve Spring (4W2471): Assembled length ... 53.24 mm (2.096 in)Load at assembled length ... 245 24 N (55.1 5.4 lb)Operating length (min) ... 38.96 mm (1.534 in) Load at min operating length ... 805 40 N (181.1 9.0 lb)Free length after test ... 59.5 mm (2.34 in)Outside diameter ... 37.31 mm (1.469 in) The following springs (inner and outer) are used on the exhaust valves with the 70 PSI Williams Blue-Ox Exhaust Brake.Inner Valve Spring (9Y3327): Assembled length ... 50.24 mm (1.978 in)Load at assembled length ... 264 26 N (59.4 5.9 lb)Operating length (min) ... 36.14 mm (1.423 in)Load at min operating length ... 445 22 N (100.1 5.0 lb)Free length after test ... 70.9 mm (2.79 in)Outside diameter ... 29.83 mm (1.174 in)Outer Valve Spring (9Y3326): Assembled length ... 53.24 mm (2.096 in)Load at assembled length ... 521 52 N (117.2 11.7 lb)Operating length (min) ... 38.96 mm (1.534 in)Load at min operating length ... 992 50 N (223.2 11.3 lb)Free length after test ... 69.04 mm (2.718 in)Outside diameter ... 42.61 mm (1.678 in)(2) Height to top of valve guide ... 32.3 0.8 mm (1.27 .03 in)(3) Diameter of valve stem (new) ... 9.441 0.008 mm (.3717 .0003 in) Coat the intake and exhaust valve stems with 8T2998 Camshaft Lubricant prior to installation in the cylinder head.Use again minimum:1W3860 Exhaust ... 9.408 mm (.3704 in)2W2622 Intake ... 9.408 mm (.3704 in)Bore in valve guide with guide installed in the head (new) ... 9.487