PROBLEMS WITH DIESEL GENERATORS
Upon sailing one morning the motorman noticed water leaking out from the cracked cylinder Head of No2 unit of Generator.
Engine sound also noticed to be a bit different. It was informed to 5th engineer. Other engine started and running engine stopped.
Unit No 1 opened up. Found inlet valve broken, bottom broken and bottom half portion found inside the unit. Cylinder head bottom broken and cooling water badly leaking into the unit. Water also went to the other unit through scavenge manifold. Also No. 4 and 7 unit connecting rod found slightly bent. Same thing had occurred on other generator 2 a month back.
On inspection found this incident was occurring due to rocker arm Lub Oil failure and the clearing between the valve stem and bush. Also due to luboil failure rocker arm bush was getting damaged. This cause increased in tappet clearance. Accumulation of this problem lead to breaking of Valve and Damaging unit parts.