engine gauge panels

Mitsubishi S12R low oil pressure cause



I have written many times about how important feedback of information on engine performance is, and how it can be used to prevent failures and downtime.

And recently, we saw a case in point where the initial information needed to be explored further to prevent bigger problems.

It started when the Superintendent of a vessel rang us up because their Mitsubishi S12R engine was stalling whilst out at sea.

That’s a pretty big problem, so we deployed straight to the vessel once it was back in port.

Once on-board, we found that the reason the engine kept cutting out was because the low oil pressure alarm was doing its job and stopping the engine from running.

As they say ‘time is money’, and the quick fix would have been to disengage the alarm, and monitor the engine, meaning that the vessel could get back out to sea and back to earning.

But as was proved, that would have been completely the WRONG thing to do. The trouble is, we see it happen so often…

Fortunately for the operator, Fraser (our engineer) didn’t even contemplate that.

Instead, he carried out investigations that helped him to work out the root cause of the oil pressure – water contamination.

Here’s what he saw when he investigated:


Yes, that’s water coming down the liner, past the piston.

The water was coming down the liner as a result of perished O-rings on two of the cylinder liners; and because they’d been running for many hours with contaminated oil, the only option to bring reliability back to the engine was to carry out a complete overhaul.

That’s exactly what we did, covering the cylinder heads, pistons, liners, turbo and injectors, to give the Superintendent the engine reliability he needed.

Once again, this story highlights the importance of ensuring that these warning signs are investigated and acted upon and things are dealt with properly, just as this operator did.

If you’ve got any engine issues you would like help with, email us info@bartechmarine.com or call +44 (0)1206 673101.

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