930103-0800 Tohatsu NUT

Illustration 1 g00290110
(1) Assembled height of rocker arm support dowels ... 8.0 1.0 mm (.32 .04 inch) (2) Inside diameter of valve guide bore in cylinder head ... 16.031 0.028 mm (.6311 .0011 inch) (3) Assembled height of valve guides ... 20.0 2.0 mm (.79 .08 inch) (4) Assembled height of bridge dowels ... 105.0 2.0 mm (4.13 .08 inch) (5) 1W-1749 Spring inner spring for valve Length under test force ... 79.3 mm (3.12 inch) Test force ... 361 36 N (80 8 lb) Free length after test ... 107.0 mm (4.21 inch) Outside diameter ... 47.9 mm (1.89 inch) (6) 1W-1748 Spring outer spring for valve Length under test force ... 84.9 mm (3.34 inch) Test force ... 758 76 N (170 17 lb) Free length after test ... 114.0 mm (4.49 inch) Outside diameter ... 68.0 mm (2.68 inch) (7) Procedure to tighten the cylinder head nuts
Lubricate the washer face and the stud threads with 5P-3931 Anti-Seize Compound .
Assemble the seals, the gasket and the washers to the cylinder head. Tighten the nuts by hand.
Use the 156-7163 Stud Tensioner Tool Group to apply tension to all four studs at the same time.Tension the studs to the following value. ... 125000 2500 kPa (18130 363 psi)
Use a ratchet and a 1/2 inch drive extension to tighten the nut against the cylinder head assembly.
Slowly release the hydraulic pressure.
Repeat Step 3 through Step 5. (8) Tighten the pressure relief valve to the following torque. ... 275 25 N m (200 18 lb ft) (9) Thickness of combustion gasket ... 4.20 0.05 mm (.165 .002 inch)Surfaces must be parallel within the following dimension. ... 0.03 mm (.001 inch) (10) Angle of valve face Angle of the face of the inlet valve ... 20.25 0.10 degrees Angle of the face of the exhaust valve ... 30.25 0.10 degrees
Illustration 2 g01182869
(11) Depth of bore for inlet valve seat insert ... 29.00 0.15 mm (1.142 .006 inch) (12) Diameter of inlet valve stem ... 15.980 0.007 mm (.6291 .0003 inch)Install the valve guide into the cylinder head. The bore in the valve guide is the following dimension. ... 16.031 0.028 mm (.6311 .0011 inch)Note: The inlet valve stems should be coated with 8T-2998 Lubricant . This should be prior to the installation in the cylinder head. (13) Inlet valve seat insert Diameter of inlet valve seat insert ... 97.195 0.015 mm (3.8266 .0006 inch) Diameter of the pilot for the inlet valve seat insert ... 96.9 0.04 mm (3.8150 0.0016 inch)Bore in head for inlet valve seat insert ... 97.000 0.025 mm (3.8189 .0010 inch) (14) Angle of face of inlet valve seat insert after machining ... 20.50 0.15 degrees (15) Maximum recess from the closed valve face to the surface of the cylinder head ... 5.0 mm (.20 inch) (16) Outside diameter of the head of the inlet valve ... 90.00 0.20 mm (3.543 .008 inch) (17) The minimum valve lip thickness that can be used again is the following dimension. ... 4.80 mm (.189 inch)
Illustration 3 g00308583
Exhaust Valves (18) Depth of bore for exhaust valve seat insert ... 40.00 0.25 mm (1.575 .010 inch) (19) Diameter of exhaust valve stem ... 15.980 0.007 mm (.6291 .0003 inch)Install the exhaust valve guide into the cylinder head. The bore in the exhaust valve guide is the following dimension. ... 16.031 0.028 mm (.6311 .0011 inch)Note: The exhaust valve stems should be coated with 8T-2998 Lubricant . This should be prior to the installation in the cylinder head. (20) Diameter of exhaust valve seat insert ... 93.650 0.015 mm (3.6870 .0006 inch)Bore in head for exhaust valve seat insert ... 93.500 0.025 mm (3.6811 .0010 inch) (21) Angle of face of exhaust valve seat insert after machining ... 30.75 0.25 degrees (22) Maximum recess from the closed exhaust valve face to the surface of the cylinder head ... 5.0 mm (.20 inch) (23) Outside diameter of the head of the exhaust valve ... 90.00 0.20 mm (3.543 .008 inch) (24) The minimum valve lip thickness that can be used again is the following dimension. ... 4.80 mm (.189 inch)