Vessel engine block blown open in and around cylinder

  • Safety Flash
  • Published on 9 July 2018
  • Generated on 16 February 2026
  • IMCA SF 14/18
  • 1 minute read

A severe engine failure occurred during a major vessel overhaul. 

What happened?

The connection rod on cylinder #12 parted from the connecting rod cap and punched a hole in the engine block. The engine had been running for 17 hours, carrying approximately a 20% load.

Parts of the engine block were found spread around the engine room, indicating that the outcome of the event could have been much worse, with potential for personnel injuries and a fire. At the time of the event, the engine room was vacated for lunch. No injuries were sustained, there was no spill of fluids and no fire.

Showing the connection rod on the cylinder blown through the engine block

Showing the connection rod on the cylinder blown through the engine block

Debris found spread around the engine room

Debris found spread around the engine room

What went wrong?

Failure to change out and correctly torque up four temporarily installed connection rod bolts. The four bolts were temporarily installed. Preliminary investigation revealed high pressure on work schedule, poor handovers, lack of checklists and incorrect marking of cylinder #12.

What actions were taken? What lessons were learned?

Our member noted the following:

  • Focus on correct and sufficient management of change (MoC) and handovers processes.

  • Use of checklists and marking/signage during work on engines.

  • Limit personnel exposure during start-up of overhauled engines.

Latest Safety Flashes:

Fall from height during mooring due to rope tension reaction

Rope became entangled with the propellor during mooring operations of a tanker causing the operator to lose balance and fall onto the lower platform.

Read more
Missing protection – progressive wear on hydraulic hoses causes damage

During an inspection, several hydraulic hoses and fuel hoses were found in direct contact with surrounding surfaces and sharp edges.

Read more
Small engine room fire – flammable object ignited

While ramping up the starboard main engine, a small flammable foreign object ignited.

Read more
Positive: damage to Fast Rescue Craft davit wire rope caught before failure

During routine checks, it was observed that the FRC davit wire rope had a visible fracture at the socket termination area.

Read more
BSEE: Miscommunication and trapped pressure causes injury during valve maintenance

BSEE has published Safety Alert 509 relating to a gas release incident on an offshore platform.

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.