What Does TBN Mean And Why Does It Matter For Ship Propulsion?

What Does TBN Mean And Why Does It Matter For Ship Propulsion?

Marine engine oils

You might recall from high school chemistry lessons that ‘an acid plus a base equals a salt plus water’ a well known saying to many thousands of students; the TBN of a marine lubricant actually means Total Base Number.

A higher total base number means that a crank case or marine engine oil is more alkaline in nature due to the additives package with which the base oil is blended. As an aside, this high TBN additive package would likely damage the exhaust catalyst in a modern car or van…

Why Is This A Bit Unique To Shipping?

In short, despite the proliferation of press releases about use of biofuels and liquified natural gas in dual fuel trunk piston engines, many ship engines continue to run on HFO or heavy fuel oil.

HFO is known also as residual fuel, a helpful name pointer to the nature of this heavy black treacle-like fuel that is left behind after cracking by distillation has taken off fractions like DERV, petrol, LPG, kerosene and so on.

Ships Engine Oil Supplier

Residual fuels are cheap, that is the bottom line of why they are still the fuel of choice for the maritime industry with cargo vessels, bulk carriers, and tankers.

In the case of military naval vessels this seems to be less common with the use of gas turbine engines or high/medium speed diesel engine gensets from brands like MTU, Scania, or Wartsila using lighter distillates, marine diesel, or kerosene derived jet fuel.

The Acid Problem

Heavy fuel oil often contains a fairly high amount of sulphur (or sulfur) which, when combusted in the cylinders of a ship’s engine, leads to production of sulphuric acid, this damaging by-product of combustion needs a ‘base’ (another name for an alkali) to neutralise this acid.

Ship Engine Oil

This is the simple reason why trunk piston engine lubricating oil and engine oil for crosshead 2 stroke and 4 stroke engines on ships will often have a relatively high TBN.

It plays the role of an alkaline neutraliser in engines running on HFO fuel as well as acting as a cylinder lubricant to stop ring sticking on the liners.

Because of the huge size and specifically the stroke length of the cylinders, marine engine oils for these large powerplants from Bergen, MaK, MAN Energy Solutions, and Daihatsu, the cylinder oil is generally fairly viscous so that it stays in place on cylinders that can be 2 to 3 metres in height.

Talk over your ship oils needs with NauticOil, the specialists in supply of lubricating oils, hydraulic oils, and marine greases with fast deliveries to yacht marinas, ship yards, ports and dry docks.

Marine Engines

Marine Engines – The World Of Caterpillar

Marine Engines Videos

These videos give you a fascinating insight to the MaK medium-speed marine engines plant in Kiel and the CAT marine engines plant in South Carolina, USA.

Discover the fascinating world of marine engines with both high-speed engines from Caterpillar like the C32 and C7.1 and the MaK stable of medium speed ship propulsion engines and auxiliary gensets, made in Germany.

Colossal crankshafts, phenomenal pistons, 2.5 metres of stroke per cylinder, these dual fuel trunk piston engines output multiple thousands of kilowatts of power running on natural gas or heavy fuel oil.

Watch the processes here and if you need ship oil or hydraulic oils just drop us an email to info@acute.uk.com

Oil For Boat Engine

The specialist NauticOil 15W 40 oil for boat engine is optimised for use by heavy-duty diesel engines such as Cat, MTU, John Deere or Perkins brands of 4 stroke power plants.

Oil For Boat Engine

Discourages crank case and component corrosion, ring sticking, and lowers exhaust emissions and NOx or particulates with its low SAPS E9 standard formulation.

Blended from mineral oils and specialist additives, this 15 40 marine oil is suitable for SHPD super high performance diesel engines that are used in the marine environment where they run at high revolutions for extended periods.

Jet Boat At Speed

Lube Oil For Fishing Boats

Engine Oil For Fishing Vessels

Try our marine engine lube oils for high-speed diesel engines in fishing vessels, coasting boats, and tug boats.

Purpose designed and formulated from base oils with specialist additives for use in Scania, Volvo Penta, Beta marine, Baudouin, Renault, Perkins, and Caterpillar marine engines and auxiliary generators on offshore platforms and shipping.

Baudouin marine diesel engine tier ll
Engine Oils

Our lubricants are approved for use with Cummins, Deutz, Mercedes-Benz, Renault, and DAF diesel engines for both Euro 5 and Euro 6 that have after treatment systems, EGR, or SCR catalysts.

The 15W40 marine engine oil and the 10W30 product are both low SAPS oils to E9 low emissions standards, SAPS means sulphated ash, phosphorus, and sulphur.

These oils bring the latest standards of performance from the on-road automotive lubrincant technologies to the marine, offshore, and shipping sector.

Marine Engine Oil

Our mineral lube oils are suitable for both naturally aspirated and turbo-charged boat engines. They are made in the UK to high specifications.

Diesel engines in fishing vessels or tub boats have an arduous life with a wide range of throttle settings and some short burst manoeuvring before heavy bursts.

NauticOil products give both top engine protection from cylinder polishing for day-in, day-out reliable output, easy turn-over for starting and good thermal stability and a TBN number of 9.5.

With the Skipper show now behind us it is time to consider if your engine could do with an oil change to keep it running at its best!

Call us on 01324 309100 or email info@acute.uk.com or maybe you would be interested to watch this video of 1000hp Scania engines on a Swedish boat?

US Coast Guard RBM – 1650 Horsepower From MTU Engines

US Coastguard RBM Launch

In this very interesting video from the Smarter Every Day YouTube channel the author Destin is given a feel of the power of a pair of Detroit Diesel 2-stroke 6-cylinder engines of 825 horsepower on a waterjet propelled and super manoeuvrable US Coastguard response boat medium – the RBM.

As well as the gulf coast sunshine, the remarkable coasty training in evidence, and sheer power of the boat. you get an insight into how important keeping an eye on your 15W/40 marine engine oil is.

The US Coastguard utilise a very neat mechanical device called the falling ball as in this image that allows them to test oil for fuel ingress right there and then on the water after taking oil samples!

Marine Engine Oil Test Device

All in all, it is mighty impressive to see a jet boat like this at full speed and then basically do a handbrake skid to a halt – not to far removed from the reversing thrust buckets on a commercial airliner when it comes in to land on the runway!

Destin goes interesting places like Opal mines, nuclear submarines, and literal rocket factories as well as meeting Mr Obama – his channel can be seen here. 

MTU gas engines

A Fuel First On MTU Gas Engines For Dutch Ferries


Selected by a Dutch operator of catamarans and inland ferries around the Zudier Zee area, these MTU Series 4000 marine engines are powered by natural gas. You can watch a video of these impresssive and eco-friendly power plants below.

As a single fuel engine which comply with emissions regulations with out even needing to have EGR or catalytic treatment of exhaust fumes!

It is an impressive achivement for MTU marine propulsion solutions that is part of wider Rolls-Royce Group.

Marine Engine Oil

Marine Engine Oils Supplier

Marine engine oils brand NauticOil offers a SAE 15W-40 and 10W-30 engine oils that are ideal for all engine types, petrol or diesel, installed in canal boats, speed boats, launches, catamarans, and fast ferry boats and similar vessels.
Volvo Penta Marine Diesel Engine

Above: The Volvo Penta D13 Marine Diesel Engine As Fitted To HMS Cutlass.

Outboard 4 stroke engines requiring a lubricant with this level of modern performance and low emissions are generally 10W-30 and to the E9 standard as our product is.

Both options in our range are low SAPS products so are ideal where an exhaust gas re-circulation system is in use or SCR catalyst.

Baudouin marine diesel engine tier ll