5.5 Antifreeze

The predecessor version of the MTU Fluids and Lubricants Specifications used the term "Corrosion inhibiting antifreeze". For clarity purposes, this publication uses the term "Antifreeze" will be used. Antifreeze is necessary for engines without heating facilities and for operation in areas where below-freezing temperatures may occur. The product BASF G206 is available for use at arctic temperatures (< -40 °C). Most of the antifreezes approved at MTU are based on ethylene glycol. Exceptions: • Ready mixture of Fleetguard PG XL based on propylene glycol (→ Page 171) • Concentrate BASF G206 as a mixture of ethylene glycol and propylene glycol Provided that they are used in approved concentrations, antifreezes approved by MTU provide effective protection against corrosion, see Operational monitoring (→ Page 31). The antifreeze concentration must be determined not only in accordance with the minimum anticipated temperatures but also with the corrosion protection requirements. For approved coolant additives for the individual engine series, refer to chapter "Approved coolants" (→ Page 132).

Special approvals presently in effect remain valid. Coolant additives containing nitrite must not be used in conjunction with coolers that contain brass!

Marine engines are subject to the following limitations when using antifreezes:

• Series 538, 595 and 8000:

The use of antifreezes is not allowed for these engines. • Series 956-01, 956-02, 1163-02, 1163-03, 1163-04:

These engines are fitted with heating units. Because of their cooler capacity, antifreezes must not be used. • Series 099, 183, 396:

Antifreezes may be used with these engines at seawater temperatures up to a maximum of 20 °C max. • Series 2000 and 4000:

On these engines with installed heat exchanger, antifreezes may be used at seawater temperatures up to a maximum of 25 °C. The use of antifreezes is generally not allowed on engines with no installed heat exchanger. Ensure that the heat exchanger not installed on the engine is sufficiently dimensioned.

The specified maximum values for the seawater temperatures apply to all engines on a vessel that are cooled with seawater, e.g. drive motor and onboard power generator. The possibility of using antifreezes for the above-mentioned series for other applications (e.g. genset, rail) is described in the overview in the chapter "Approved coolants"(→ Page 132).

Note:

Propylene glycol-based antifreezes are stipulated for use in some types of applications. These products have a lower thermal conductivity than the usual ethylene glycol products. This results in a higher temperature level in the engine. Flushing with water is required at every change to a different coolant product. For preserved engines (new engines, field engines, reserve stock engines, etc.), a flushing run must be carried out prior to filling with engine coolant if the engines were preserved with an emulsifiable corrosion inhibitor. The necessary work is described in the chapter "Flushing and cleaning specifications for engine coolant circuits" (→ Page 172).