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29/04/2024

Freefall lifeboat does not start. Part 1. Troubleshooting

Lifeboats on a ship are usually inspected once a week, testing the starting condition of the engine on two batteries, rudder, telegraph-propeller, lighting, as well as the condition of batteries and chargers.

The lifeboat does not start. Troubleshooting

Despite regular checks, the lifeboat's engine may stop starting at any time. This is exactly the situation that occurred on the ship during the inspection of the boat by the port inspector.

Selecting a battery for starting the boat
Selecting a battery for starting the boat

When selecting the first (main) battery to start the engine, it turned out that the boat would not start, although all the lighting was working. The indicator on the charger lights up green, which indicates the normal state of the battery.

Electrical diagram of batteries, charging and lighting of the freefall lifeboat
Electrical diagram of batteries, charging and lighting of the freefall lifeboat

After an unsuccessful attempt with the first battery, the engine was started using the second (emergency) battery. This time it was successful.

Lifeboat batteries
Lifeboat batteries

As a result of checking with a battery tester, it was discovered that the capacity of the first battery is near zero. Despite the fact that the battery indicator is green and the battery voltage is about 13V.

Checking the first battery (low capacity)
Checking the first battery (low capacity)

The voltage of the first battery is about 13V
The voltage of the first battery is about 13V

Checking the first battery (green indicator)
Checking the first battery (green indicator)

We can conclude that the battery capacity for lighting is quite enough, but there is not enough starting current to start the lifeboat engine. In addition, it turned out that this battery is almost 4 years old since it was installed. Typically, the service life of maintenance-free acid batteries on a ship is about 4 years, after which it is recommended to replace them with new ones.

Checking the second (emergency) battery
Checking the second (emergency) battery

Checking the second (emergency) battery also showed an unsatisfactory result, because its capacity is at the “weak” level. This battery was also installed about 4 years ago, so its capacity has dropped.

Checking a new battery (12V 62Ah 590A)
Checking a new battery (12V 62Ah 590A)

It is very important when receiving a new battery to immediately check its capacity with a battery tester, because it is not enough just to measure its voltage and look at the green indication.

Battery tester
Battery tester

After installing the new battery, the freefall lifeboat was tested and showed successful operation on both batteries.

By the way, if you work on tankers, then this battery tester will not suit you. I recommend using an electronic battery capacity tester.

Read also the second article on this topic: “The lifeboat engine does not start. Part 2. Troubleshooting,” which details another common problem with starting lifeboats, namely problems with the starter motor and relay of gear wheel.

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