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COOLANT WT SUPRA - Total Lubmarine

Utilizing the latest organic technology to reduce maintenance costs, WT SUPRA delivers high-quality performance and extended service life to equipment. Here we take a detailed look at the marine and stationary engine coolant and corrosion inhibitor.

Technical overview

WT Supra is an environmentally friendly inhibitor concentrate. Based on patented carboxylate additive technology, providing long-life corrosion protection in aqueous solutions for all engine metals, including aluminum, iron, copper and solder alloys.

Mixed with the appropriate amount of water, WT Supra is recommended as a coolant, flushing fluid or hot test fluid for engine blocks and all cooling systems. During extensive field testing, the synergistic combination of mono and di-carboxylic additives has proven to provide superior protection for at least 32,000 hours in marine and stationary applications. The product is compatible with glycol-based engine coolants.


WT Supra offers a number of benefits to the engine designer as well as to the user, including:

  • Extended and superior corrosion protection through a synergistic combination of additives
  • Superior technology provides more flexibility to engine design
  • Excellent protection of thermostat, radiator and water pump
  • Reliable depletion free and stable inhibitor
  • Improved hard water stability absence of silicates and phosphates
  • Saves time and money maintenance-free inhibitor
  • Environmentally friendly by using carboxylic additives in the inhibitor package


WT Supra provides long-life protection against all forms of corrosion by using optimized and patented organic corrosion inhibitors. Excellent and lasting high-temperature corrosion protection is provided for the aluminium heat transfer surfaces contained in modern engines. The inhibitor package of WT Supra offers excellent cavitation protection even without using nitrite or nitrite-based supplemental coolant additives (SCA’s).

Outstanding performance

Thanks to its organic technology, WT SUPRA protects circuits much better against cavitation and corrosion than conventional "water treatment" products. The absence of any inorganic ingredients, such as phosphates or nitrites, means that no hard deposits are formed, especially around the top of liners, cylinder heads, heat exchanger tubes and electric heaters. As a result, heat transfer is sustained, anti-corrosion and anti-cavitation properties are maintained.        In addition, there is no risk of pipe erosion, due to hard particles in circulation, and the circuit remains clean.

Bigger savings, better protection

In marine application, the concentration of WT Supra should not be lower than 5 vol.% At this dosage, the recommended lifetime is at least 32,000 hours. When WT Supra is replenished to compensate for leakage, the cooling water can be considered as fill for life.

Small marine engines sometimes require limited frost protection. This can be obtained by using the adequate dosage of Coolelf Auto Supra, based on ethylene glycol, supplemented with 5 vol.% WT Supra. For frost protection of -10 and -15°C, the required Coolelf Auto Supra dosages are respectively 22 and 29 vol.%

At 5 vol.% WT Supra performs as a flushing fluid to clean cooling systems that were filled with other inhibitor packages.

OEM approved

WT Supra is fully approved by most major engine designers including Caterpillar, Detroit Diesel,  MAK, MAN Energy Solutions, 2 and 4 cycle engines, MAN (Ruston) MTU Rolls-Royce Wärtsilä diesel, gas and dual-fuel engines WinGD diesel, gas and dual-fuel engines Yanmar.

Compatible services

There are two key services to support customers using WT SUPRA, Diagomar Coolant and Tech’Care Coolant.

Diagomar Coolant provides a complete diagnosis of the condition of the coolant, as well as offering recommendations of maintenance and draining to optimize the operating conditions of the customer’s equipment. In short, it enhances both the reliability and service life of the equipment, ensuring operational cost savings.

The Tech’Care Coolant field test kit is ideally suited for the monitoring of engine cooling fluids on-site and facilitates the checking of important characteristics of the coolant. This includes the WT SUPRA concentration, pH, chloride content, hardness and temperature. The kit includes all accessories, reagents and operating manuals for performing and understanding 100 tests.

To find out more about WT SUPRA, visit our section.

Protection of the Cylinder Liners Liners after 400 hours of thermal shock tests on 6.2 L engine
Protection of the Cylinder Liners Liners after 400 hours of thermal shock tests on 6.2 L engine
Protection of the Heat Exchanger Tubes Results after 18 months on 4MW Wärtsilä SACM preheating circuit.
Protection of the Heat Exchanger Tubes Results after 18 months on 4MW Wärtsilä SACM preheating circuit
Chemistry Technical