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Anyone here use synthetic oil in ship engines?

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frankiee

Marine/Ocean
Jun 28, 2005
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We do not use synthetic oil and I was thinking that must be be cause it is not as good as some claim.
If it would make a $5,000,000 engine last longer or burn less fuel then the ships would have it.
What do you people use???
 
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Hello frankiee

In marine big engine is better to use mineral in the brand new engine. The new engine piston and cylinder, valves dimension is a little bit oversize and special shaped. Mineral oils help matching these parts and allow to wear it. After this process combustion chamber is tigth. You can not do it with synthetic oil.
Also marine engine is low or medium revolute engine and wearing is not so big like in cars high revolute engine. Marine engine have got also quite big capacity of crankase with large amount of oil. Because of that is too expencive and not necessary use synthetic oil.
But I think is nothing against apply synthetic oil after gring in trial.
 
Marine engines, especially 2-stroke engines, use up quite an amount oil. The main advantage of synthetic oil is its longer useful operating life. So, you'll improve the service life and overall quality of the oil, and then blow it out the chimney...
 
So what size and brand is that 5Mil engine?

Synthetic vs Mineral. I'm don't know, but what about spillage of one vs the other? And time use limits? Cost of course. I was at first thinking burning and by products from. But recycled motor oil is all dumped into the same container and then used to mix bunker oil. Unless that has changed in the last 15 or so years. I'm sure during oil changes that the used engine lube oil is used as a blend to fuel the engine.
 
Shipboard synthetics used to be a no-no due to the fact that they broke down when exposed to water. This is no longer the case and according to my local Mobil rep, they now separate from water better than non-synthetics.

5 million dollar engine I am guessing is probably a big Sulzer type, 2 stroke with an exhaust valve instead of an exhaust port, with a crosshead system. Depending on the exact configuration, you COULD use a synthetic but with the consumption involved in your cylinder lube system your costs are going to go up some due to the difference in costs of the oil. Honestly though, I really dont know how much you would gain by doing this. As long as you are having samples lab tested regularly and keeping your purifiers/clarifiers in good shape, regular oil will give you the protection you need in your engine.

The biggest thing you need to worry about is fuel dilution. You can find this by using a flow stick once a month to check the viscosity of your oil.
 
Re blending oil with fuel. I had a discussion a couple of years ago on this subject with a Cat representative. They had a large number of gensets on lease in the 1000 to 1500 HP range. He told me that with the new fine pattern injectors and the newer filters needed for the new injectors that blending used oil with the fuel was no longer an economic viability. The cost of replacing plugged filters exceeded the savings in fuel.
This is probably not an issue yet with large marine engines, but probably will be in the future.
yours
 
May be worth investigating on medium and high speed diesels.For new engines you will want to verify if the synthetic lube is approved for use by the engine builder. A lot of the smaller synthetic lube suppliers are unwilling /unable to pay for bench testing of each engine type.
 
The marine engines are very large ( 10,000 bhp to 93,000bhp), and having crank case system oil from some 15000 ltrs to 40,000 ltrs or more. Being cross head type the combustion products seldome enteres the crank case. Thus relatively the oil stays clean for a very long duration.
However the system oil passes through the centrifuges continuously to remove any combustion products entered into the system.
For this reason the Large marine engines need not use the synthetic oil for their system oil.
However the case of Lubrication of Turbo charger lubricating oils is different. More and more vessels using Synthetic oil for its better life with respect to the oxidation, stability and most importantly for its more running hours between renwal.
 
Hi,

We are about to embark with a new ship and running Caterpillar Synthetic Motor Oil in 2 x Series2 3516 Engines and 3 x C 18 Gensets.

All of these engines have been run for their factory and class tests with Mineral Oil, they will continue with this till after all Dock and Sea Trials when we will change over to the Synthetic Oil.

I have mede this choice based on several issues. Low Sulphated Ash (we are using ETB Exhaust Cleaners), extended change interval. The later has two points in it's favour. The cost and difficulty of disposal for the areas we work has been a problem for me in the past so I am hoping to avoid these same issues with this boat.
 
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