Specifications

14 Coolants
Emulsions of MTU-approved corrosion-inhibiting oils (1.0 – 2.0% by volume) and suitable
fresh water provide adequate corrosion protection.
Some corrosion-inhibiting oils tend to foam if used with completely demineralized water. This can
be avoided by adding an appropriate quantity of harder water.
The required quantity of corrosion-inhibiting oil is best mixed in advance in a container with 4 to 5 times the amount
of fresh water and then added to the coolant when the engine is running at operating temperature.
In maintenance stations or multi-engine installations the complete amount of coolant required should be prepared
in a separate container, it can then be used for initial filling or replenishment as required.
Under unfavorable conditions, individual cases of bacterial attack may occur in the emulsifiable
corrosion-inhibiting oils. In such cases, and after consultation with the MTU chemical laboratory, the
emulsion is to be treated with biocides.
Note:
Slight precipitation may occur where coolant emulsions are used. This is shown by a layer on the surface of the
coolant in the expansion t
ank. This is of no significance provided that the emulsion concentration remains within
the specified limit values. Change the coolant in the event of a sudden drop in coolant additive concentration
or if the additive is no lon
ger absorbed. If necessary, the engine coolant chambers are to be cleaned (see the
Flushing and Cleaning Specification for Engine Coolant Systems at t he end of this specification).
Emulsifiable corrosion-inhibiting oil must never be used for coolant temperatures >90 °C
except during test stand runs and test runs.
Emulsifiable corrosion-inhibiting oil is to be used for the Series 595, 956 and 1163
engines in
marine applications exclusively.
Emulsi
fiable corrosion-inhibiting oils must not be used with the following Series:
• Series 183
• Series 396 TB (external charge air cooling with plate core heat exchanger)
• Series 396 TE (split-circuit cooling system)
• Series 4000
• Series 8000
Corrosion-inhibiting antifreezes
General information
These antifreezes are necessary for engines without heating facilities and operating in areas
where below-freezing temperatures may occur.
Provided that the specified concentrations are maintained, the MTU-approved corrosion inhibiting
antifreezes ensure adequate corrosion protection.
The corrosion inhibiting antifreeze concentration mu st therefore be determined not only in accordance with
the minimum anticipated temperatures but with the corrosion protection requirements also.
If a higher level of corrosion-inhibiting antifreeze is used, a higher engine temperature will result.
Limitations on the Use of Corrosion-Inhibiting Antifreezes
Marine engines are subject to the following limitations when using corrosion-inhibiting antifreezes:
• Series 538, 595 and 956/1163:
These engines are fitted with heating units. Because of their cooler capacity,
corrosion-inhibiting antifreezes must not be used.
• Series 099, 183, 396:
The use of corrosion-inhibiting antifreeze in these engines is permitted only at seawater
temperatures of up to 20 °C maximum.
• Series 2000 and 4000:
Corrosion-inhibiting antifreeze may be used with these engines at seawater temperatures up to 25 °C
• Series 8000:
The use of corrosion-inhibiting antifreezes is not allowed for these engines.
A001061/33E 08-01 ©MTU
TIM ID: 0000010136 – 006