The Role of Auxiliary Engines in Emergency Situations

As a marine engineer with 20 years of experience in ship operations and engine systems, I've seen firsthand how auxiliary engines can mean the difference between a safe voyage and a maritime disaster. When the main engine fails or electrical systems go dark, your auxiliary engine in ship becomes the lifeline that keeps critical systems running.

What is an Auxiliary Engine?

An auxiliary engine is a secondary power unit aboard ships that provides electrical power and drives essential systems everything except propulsion. Unlike the main engine that moves your vessel forward, marine auxiliary engines keep the lights on, pumps running, navigation systems active, and emergency equipment operational.

Think of your auxiliary engine in ship as the backup generator for a hospital. When the main power goes out, it automatically kicks in to keep life-supporting equipment running. On ships, these engines typically generate 440V to 6600V of electrical power and can range from 850kW on smaller vessels to 1.5MW on large tankers. (ref)

The Critical Role of Auxiliary Engines in Emergency Situations

Blackout Prevention and Recovery

The most dangerous situation at sea is a complete power blackout. When this happens, marine auxiliary engines become your vessel's salvation. During blackouts:

• Navigation lights go dark, making collision risk extremely high.

• Steering systems lose hydraulic power, compromising maneuverability.

• Communication equipment shuts down, cutting off distress signals.

• Fire suppression systems become inoperable.
  

Your auxiliary engines must start within 45 seconds to restore emergency power automatically. Modern ships carry multiple auxiliary engines typically two running (one at sea, two in port) with one spare for redundancy. (ref)

Emergency Power for Critical Systems

When main power fails, marine auxiliary engines immediately supply power to:

• Emergency lighting for safe evacuation and operations

• Fire pumps for firefighting systems

• Bilge pumps to prevent flooding

• Steering gear for maintaining course control

• Communication systems for distress calls

• Navigation equipment including radar and GPS
  

Main Engine Support During Crisis

Your auxiliary engine in ship doesn't just provide backup power it supports main engine restart procedures. During main engine failure, auxiliary systems provide:

• Starting air pressure for main engine restart attempts

• Cooling water circulation to prevent overheating

• Lubricating oil pressure for safe operation

• Fuel system pressurization
  

Common Problems in Auxiliary Engines and How to Fix

Them

1. Engine Won't Start

Symptoms: No response when starting, cranking but not firing.

  Common Causes:

• Empty fuel tank or closed fuel valve

• Clogged fuel filters

• Air in fuel system

• Low starting air pressure

• Faulty starting air valves

  
  

Quick Fixes:

• Check fuel tank levels and open all fuel valves

• Replace clogged fuel filters immediately

• Bleed air from fuel system at high points

• Verify starting air bottle pressure (minimum 30 bar)

• Test starting air valve operation manually
  

2. Engine Stops Suddenly

Symptoms: Engine running normally then shuts down without warning.

Common Causes:

• Fuel system contamination

• Overheating due to cooling system failure

• Low lubricating oil pressure

• Safety system activation
  

Emergency Actions:

• Switch to standby auxiliary engine immediately

• Check cooling water flow and temperature

• Verify lubricating oil level and pressure

• Inspect for visible leaks or damage
  

3. Poor Engine Performance

Symptoms: Reduced power output, high exhaust temperatures, excessive fuel consumption.

Common Causes:

• Dirty air filters restricting airflow

• Fuel injection system problems

• Turbocharger issues

• Worn engine components
  

Solutions:

• Replace air filters every 250 hours

• Test and calibrate fuel injectors

• Check turbocharger operation and cleanliness

• Monitor cylinder peak pressures for uneven loading
  

4. Abnormal Noise or Vibration

Symptoms: Unusual sounds, excessive vibration, knocking.

  When to Stop Immediately:

• Any metallic knocking sounds

• Grinding or scraping noises

• Severe vibration increase

• Squealing from auxiliaries
  

Action Required: Stop engine immediately and start standby unit. Investigate bearing wear, misalignment, or component failure before restarting.

Auxiliary Engine Maintenance Checklist for Marine Engineers

Daily Checks (Every Watch)

• Fuel System: Check service tank levels, drain water from fuel filters.

• Lubricating Oil: Verify sump oil level and pressure readings

• Cooling Water: Monitor temperatures and pressures

• Starting Air: Check air bottle pressure and drain condensate

• Exhaust Temperatures: Log readings for each cylinder

• Visual Inspection: Look for leaks, unusual wear, or damage
  

250-Hour Routine Maintenance

• Clean lubricating oil filters

• Replace fuel oil filters

• Clean turbocharger air filters

• Service governor lubricating oil

• Lubricate fuel rack linkages
  

1000-Hour Major Service

• Crankcase Inspection: Check for contamination or wear particles

• Fuel Injector Service: Remove, pressure test, and recalibrate

• Valve Adjustment: Check and adjust tappet clearances

• Performance Testing: Record power output and fuel consumption

• Turbocharger Service: Change oil and inspect components
  

2000-4000 Hour Overhaul

• Cylinder Inspection: Check liner wear and piston condition

• Bearing Clearances: Measure and record all bearing clearances

• Crankshaft Inspection: Check for cracks and measure deflection

• Valve Timing: Verify correct timing settings

• Safety System Testing: Test all alarms and trips
  

Emergency Standby Procedures

Keep non-running auxiliary engines in standby condition for quick emergency starts:

• Pre-lubrication: Turn engine manually and operate lubricators

• Warming: Maintain engine temperature with heating systems

• Air System: Keep starting air charged and valves tested

• Fuel System: Ensure fuel is circulated and heated to proper viscosity
  

Best Practices for Emergency Preparedness

Crew Training

• Conduct weekly emergency drills with auxiliary engine startup procedures

• Train all watch engineers on troubleshooting common problems

• Maintain emergency contact procedures with shore support

• Practice blackout recovery scenarios regularly

  
  

Preventive Maintenance

• Never delay scheduled maintenance on marine auxiliary engines

• Keep spare parts inventory for critical components

• Monitor engine performance trends to predict failures

• Maintain detailed maintenance logs for each engine
  

System Redundancy

• Always maintain at least one auxiliary engine in standby condition

• Test automatic start systems monthly

• Ensure emergency fuel supplies are adequate

• Keep manual backup procedures readily available
  

When Professional Help is Essential

Some auxiliary engine problems require immediate professional assistance:

• Seized internal components (pistons, bearings, crankshaft)

• Major fuel system contamination

• Electrical control system failures

• Structural damage from overheating or mechanical failure

Never attempt to restart an auxiliary engine with these problems you risk catastrophic damage that could leave your vessel without any backup power.

Take Action Now: Don't wait for an emergency to test your auxiliary engines. Schedule a comprehensive inspection of your marine auxiliary engines today. Ensure your crew knows emergency startup procedures and your maintenance schedule is up to date.