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1.
The engine can be damaged if the antifreeze concentration is insufficient.
Corrosion.
Damage to the cooling system.
Engine housing fracture.
➤ Check coolant.
➤ Protect the coolant against freezing.
➤ Replenish immediately if necessary.
2. To test the coolant, use the coolant tester as instructed by the manufacturer.
Concentration of antifreeze is too low: Change the coolant.
Performing final work steps:
1. Screw the cover back on again.
2. Close the door.
10.4.1.3 Mixing the coolant
The coolant is a mixture of clean, fresh water and an antifreeze containing added anti-corrosion
agent.
Never use water without added coolant. Water alone is corrosive at engine operating temperatures.
Water alone does not offer sufficient protection from boiling or freezing of the coolant.
To protect against corrosion and raise the boiling point, the coolant must remain in the cooling sys‐
tem throughout the year.
The maximum permissible service life for the coolant is 3 years.
An adhesive label with the recommended mixture ratio for the coolant is fitted by the coolant
expansion tank, see Figure 39.
Fig. 39 Recommended mixture ratio for coolant
1
Water
2
Anti-corrosion agent/antifreeze
➤ Observe the coolant recommendations given in Chapter 2.8.4!
Preparing the coolant:
Precondition The coolant used must meet the specification of ASTM D4985.
10 Maintenance
10.4 Drive engine maintenance
No.: 901783 08 USE
Operator Manual Portable Rotary Screw Compressor
MOBILAIR M82 SIGMA CONTROL SMART
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