HEXA

ENGINE 51 D. Valves : 1. Check valve leakages by pouring gasoline on valve head. Gasoline must not seep past valve seat. 2. Valves with burnt heads, excessive scoring and wear on stem should be replaced. 3. Check valve seat run out with respect to valve stem. If it exceeds specified limit replace valve. No attempt should be made to straighten bent valves. 4. If valve is free from any other defects except worn out seat, then only it can be re-matched on valve grinding machine as follows:  Clamp valve on grinding machine jaws as close as possible to valve head.  Adjust grinding angle on graduated scale to achieve correct valve seat angle.  Feed valve slowly towards grinding wheel until wheel just touches valve head.  Grind at low feed until valve seat is just clean all around. NOTE  After machining the valve seat, remove the valve from the grinding machine and check valve head thickness. The minimum valve head thickness of the valve is 0.85 mm. Valve Dimensions Dimensions (Callout) Intake Valve Exhaust Valve Valve Head Diameter (A) Ø29.8 ± 0.1 mm Ø25.9 ± 0.2 mm Valve Seat Angle 45° + 15’ 45° + 15’ Valve Stem Diameter (B) Ø5.973 ± 0.007 mm Ø5.973 ± 0.007 mm Valve Seat Diameter (C) 27.7 mm 24.5 mm Valve Seat End Distance From Valve Face (D) 2.54 ± 0.08 mm 2.00 ± 0.08 mm Maximum Run out of Valve Face with Respect to Valve Stem 0.1 mm 0.1mm Maximum Run out of Valve Face with Respect to Valve Stem (C-B) 0.03 mm 0.03 mm Distance of Valve head from cylinder head mating surface with crankcase 0.23/-0.18 0.23/-0.18