OCTAMAR ™ LI-5 PLUS Marine Fuel Preservative

OCTAMAR™ LI-5 Plus is a new multifunctional additive, specifically formulated for commercial shipping & superyachts, to overcome quality issues and reduce risk when using marine distillate fuel.

Marine Fuel Changes

Distillate fuels are to become an increasing part of the marine fuel pool in commercial shipping. Heavy fuel oils are decreasing in frequency due to worldwide fuel legislation changes (MARPOL). Sulphur content is being systematically reduced which has numerous implications for commercial operators - most notably differing fuel solubility and therefore stability. Many vessels will begin to suffer fuel storage and combustion problems as a result of these changes in the coming years. OCTAMAR™ LI-5 Plus provides complete engine and fuel system protection - eliminating risks and ensuring integrity of your vessel irrespective of bunker fuel quality.

Benefits of OCTAMAR™ LI-5 Plus

OCTAMAR™ LI-5 Plus improves oxidation and thermal stability, allowing extended storage periods, protects against the potential presence of Biodiesel (FAME) and possible corrosion caused by high TAN fuels. OCTAMAR™ LI-5 Plus reduces fuel injector fouling, provides improved protection against corrosion, reduces risk of filter blocking, improves fuel lubricity, reduces wear risk of fuel pumps and fuel injection equipment. 'No-harm' tests show no adverse effects to fuels, lubricants, and OCTAMAR™ LI-5 Plus being fully compatible with engine and system materials.

Application of OCTAMAR™ LI-5 Plus

Manually dose OCTAMAR™ LI-5 Plus direct to storage/bunker tanks – prior to, or during, every bunkering OR manually dose OCTAMAR™ LI-5 Plus direct to service tank – prior to or during every filling. Use a Fuelcare injection system to dose in line. The recommended dosage rate is 1kg OCTAMAR™ LI-5 Plus per 4 tonnes fuel.

Lloyds Register Product Verification

OCTAMAR™ LI-5 Plus has been verified by Lloyds Register as of 2014. This is the first fuel additive of its kind to ever be approved by Lloyds Register Product Verification Service. The product claims have been independently tested, verified and approved by Lloyds Register. The product improves fuel against the following common fuel testing methods:
  • Oxidation Stability (ISO12205)
  • Thermal Stability (ASTMD6468)
  • Injector Fouling (CECF-23-01 Peugeot XUD9)
  • Steel Corrosion (ASTMD665 A & B)
  • Fuel Lubricity (HFRR ISO12156)
  • Filter Blocking Tendency (IP387).
As part of an injection system, OCTAMAR™ LI-5 Plus can be directly dosed into all bunkering fuels on a permanent basis at 250ppm, and also used together with KATHON™ FP 1.5 Fuel Biocide for complete protection from poor bunkering fuel quality.

OCTAMAR™ LI-5 Plus' Multiple Functions

1. Lubricity
Lubricity is defined as “The intrinsic ability of a fluid to prevent wear on contacting metal surfaces.” In the case of marine engines, poor lubricity affects mechanisms that rely on the fluid being pumped for lubrication, such as fuel injection equipment. Common misconceptions about lubricity abound including - “Increasing the viscosity of the fuel will improve the lubricity characteristics” or “It is the Sulphur in the fuel which offers the lubrication.”

Fuel Pump Tribology

Two distinct regimes of lubrication are within a fuel pump, firstly, 'Hydro-dynamic Lubrication' which relates to the oil film between moving two metal surfaces, preventing contact and therefore wear. This is affected to some extent by viscosity. Secondly, 'Boundary Lubrication' which is more critical in fuel pumps. This relates to lubrication where clearance is minimal, and moving metal surfaces are in contact. The fluid creates a mono-molecular layer on the surface of the components to reduce friction and prevent wear.

What reduces lubricity in middle distillate fuels? What are the consequences?

Hydroprocessing at the refinery to reduce sulphur levels has the side effect of removing other components of your fuel including 'N species', 'O species' and Polyaromatics amongst others. High sulphur fuel has natural lubricity from minor species. Therefore once sulphur is removed, the lubricity is also removed.

The main issue resulting from low lubricity is excessive wear of fuel injection equipment. However there are options for reducing this problem, including:
  • Increase sulphur levels
  • Less hydroprocessing - not possible for high sulphur crudes.
  • Improved pump metallurgy - increased cost to fuel injection equipment manufacturers, many old pumps already in the field.
  • Use of lubricity additives - most marine users preferred choice.
How OCTAMAR™ LI-5 Plus works:
2. Storage Stability Improvement
Fuel stability is effected by exposure to light, temperature and oxygen, and can result in excessive gum and sediment formation. This can lead to a range of issues including fuel filter plugging & injector deposition. OCTAMAR™ LI-5 Plus contains a stabiliser which is used to achieve specification limits and improve operability.

ISO 8217:2010 (Marine Gas Oil DMA) includes a limit for stability and oxidation - test method 'ISO12205' with a limit of 25g/m3. OCTAMAR™ LI-5 Plus brings fuel into line with this limit, bringing the stability rating down and reducing insolubles by 82%.

3. Injector Fouling
OCTAMAR™ LI-5 Plus contains a powerful detergent which prevents the formation of, and removes existing, deposits caused by fuel decomposition. This detergency characteristic results in optimal fuel spray pattern being maintained during engine running. In turn, this optimal spray pattern provides a number of benefits including:
  • Optimised fuel economy
  • Reduced emissions
  • Improved engine durability

In high pressure common rail engines, fuel is drawn from the fuel tank through a prefilter or stage 1 filter to take out the large particles (greater than 10 micron average particle size) and then through a transfer pump to boost the system pressure to 7-12 bar. Then a second stage or, polishing filter media, filters the fuel to 2-3 microns (4 micron or better) to ISO 4406: 12/9/6 levels of cleanliness.

After which, a high pressure intensification pump raises the system pressure to over 1600 bar to deliver to the common rail for storage and distribution to the injectors. This also raises the fuel temperature substantially to over 100°C above the fuel inlet temperature which may be up to 70°C.

The injectors are electronically controlled to open and close multiple times per combustion cycle to deliver the fuel precisely when and how much is needed. A small leakoff path returns drained fuel back to the tank. Note that the fuel can stay at high temperature and pressure for long residence times as potential energy of the pressurized fuel.
4. Filter Plugging
Middle distillate fuel instability can result in increased rates of filter plugging due to the changing fuel specifications. Filter deposits are then formed through instability, in turn caused by the fuel being exposed to high temperatures and pressures. Such high temperatures are commonplace in high pressure fuel injection systems used in modern marine diesel engines.

Industry standard tests exist to measure the filter blocking tendency of a middle distillate fuels - these tests measures the pressure difference across a filter 'Filter Blocking Tendency' or 'F.B.T.' - any value below 1.41 is considered satisfactory. In-house laboratory tests show OCTAMAR™ LI-5 Plus brings fuel with high filter blocking tendency down from to 1.00 using various degraded fuels. This has been independently verified by Lloyds Register in approving OCTAMAR™ LI-5 Plus for their Product Verification Scheme.

OCTAMAR ™ LI-5 PLUS Documentation

Documentation for the safe & effective use of OCTAMAR™ LI-5 PLUS Marine Fuel Preservative:

OCTAMAR™ LI-5 PLUS Brochure » Other languages:(En Français, En Español, In Italiano)

OCTAMAR™ LI-5 PLUS Product Data » Other languages:(En Français, En Español, In Italiano)

OCTAMAR™ LI-5 PLUS Safety Data »

Diesel Bug - Sampling, Testing & Treatment advice for Superyachts including MARPOL Annex VI advice, KATHON™ FP 1.5 Fuel Biocide & OCTAMAR™ LI-5 Plus:

Monaco Yacht Show Presentation »

OCTAMAR ™ LI-5 PLUS Distributors

OCTAMAR™ LI-5 PLUS is only available from selected stockists:
A.S.A.P. Supplies (U.K.)

A.S.A.P. Supplies
Ellough Industrial Estate
NR34 7TD
Tel: +44 (0)1502 716993

SilMid Ltd (U.K.)

SilMid Ltd
Roman Way
West Midlands
B46 1HG
Tel: +44 (0)1675 432850

Pinmar Supply (Majorca, Spain)

Pinmar Supply (Palma)
Camí Escollera 5
07012 Palma de Mallorca
Tel: +34 971 713 744

J.M. Scicluna (Malta)

Oleander Str.
St. Julians
STJ 1913
Tel: +356 2135 3388 / +356 99498558

Marine Technical Assistance (Sardinia, Italy)

Via Piovene 6
07026 Olbia (OT)
Tel: +39 328 1956056

Freedom Maritime (France)

4 Avenue Mirabeau
06600 Antibes
Tel: +33 4 93 34 01 68