AUXILIARY-DRIVE CHAIN BREAKAGE


Main Engine was a 6L80MC MAN B & W derated to run at 77 rpm. The vessel was recently taken over from another management company and was running @ 71 rpm.

The turning gear was not functional because of some problems. To meet the Charter party demands rpm was increased from 71 rpm to 75 rpm so as to reach the loading port on time. But after two days the M/E tripped and stopped due no cylinder oil flow.

When the lubricator was checked we found the shaft not rotating. On opening the chain case it was found that the aux. Chain was broken and timing of the lubricator and starting air distributor had been altered. Timing of the lubricator was adjusted by turning the driver wheel but for the start air distributor the chain block had to be used to turn the driver wheel.

So it was ascertained that the start air distributor shaft is seized. The whole start air distributor was removed and overhauled. Found that there is no lubricating hole in the start air dist. as per original drawings. Same drilled and starting air dist. assembled and put in place.

The engine was turned with the help of blowing 30 kg air in the engine units which are at TDC through indicator cock connection. Also a hyd. Jack was used to turn the fly wheel.
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