SAFARI

50 4 DLT ENGINE CYLINDERHEAD U sing a straight edge and feeler gauge, check cylinder head mating surface with crank case. Refer Figures. 81 & 82 I f unevenness exceeds permissible limits, replace cylinder head. CYLINDERHEADTOPANDBOTTOMSURFACERE- MACHINING IN SERVICE IS NOT RECOMMENDED. VALVES C lean valves. Remove adhering oil, carbon etc. V alves with burnt heads, excessive scoring and wear on stem should be replaced. C heck valve head thickness. If it is less than 1 mm replace valve. C heck valve seat run out with respect to valve stem. R efer Figure 83 If it exceed specified limit replace valve. No attempt should be made to straighten bent valves. If valve is free from any other defects except worn out seat, then only it can be re-machined 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 grinding valve head thickness should not be less than 1 mm. Fig. 81 Fig. 82 Fig. 83