812939A18 Mercury GASKET SET, Powerhead

(1) 4N5906 Spring for valves (new): Length under test force ... 54.99 mm (2.165 in)Test force ... 344 34 N (77 7.6 lb)Use again minimum load at length under test force ... 291 N (65.4 lb)Length of spring at valve open position ... 42.93 mm (1.690 in)Use again minimum load at valve open position ... 817 N (183.6 lb)Free length after test ... 62.7 mm (2.47 in)Outside diameter ... 31.75 mm (1.250 in)Spring must not be bent more than ... 2.18 mm (.086 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 0.010 mm (.3717 .0004 in) Use again minimum diameter of intake and exhaust valve stem ... 9.408 mm (.3704 in)Bore in valve guide with guide installed in the head (new) ... 9.487 0.025 mm (.3735 .0010 in)(4) Diameter of valve head: Exhaust valve ... 41.81 0.13 mm (1.646 .005 in)Intake valve ... 44.98 0.13 mm (1.771 .005 in)(5) Angle of intake valve face Angle of exhaust valve face ... 44 1/4 1/4 degree (6) Depth of bore in head for valve seat insert (new) ... 13.01 0.35 mm (.512 .014 in)(7) Diameter of valve seat insert for exhaust valve ... 42.850 0.013 mm (1.6870 .0005 in) Bore in head for valve seat insert for exhaust valve ... 42.774 0.025 mm (1.6840 .0010 in)(7) Diameter of valve seat insert for intake valve ... 46.025 0.013 mm (1.8120 .0005 in) Bore in head for valve seat insert for intake valve ... 45.949 0.025 mm (1.8090 .0010 in)(8) Angle of face of intake valve seat insert ... 30 1/4 1/2 degreeAngle of face of exhaust valve seat insert ... 44 3/4 1/2 degree(9) Dimension from end of closed valve to machined face of head. Maximum permissible dimension:New 115-2368 Inlet & 115-2367 Exhaust valves.Below (recessed from) machined face ... 1.22 mm (.048 in)Above (extended from) machined face ... 0.04 mm (.0016 in)All other new Inlet & Exhaust valves.Below (recessed from) machined face ... 1.22 mm (.048 in)Above (extended from) machined face ... 0.20 mm (.008 in)Reconditioned 115-2368 Inlet & 115-2367 Exhaust valves.Below (recessed from) machined face ... 1.70 mm (.067 in)Above (extended from) machined face ... 0.04 mm (.0016 in)All other reconditioned Inlet & Exhaust valves.Below (recessed from) machined face ... 1.70 mm (.067 in)Above (extended from) machined face ... 0.20 mm (.008 in)(10) Outside diameter of the face of the valve seat insert: Exhaust seat ... 40.41 0.13 mm (1.591 .005 in)Intake seat ... 44.04 0.13 mm (1.734 .005 in)(11) "Use again" thickness of valve lip: Exhaust valve ... 2.03 mm (.080 in)Intake valve ... 2.51 mm (.099 in)