Fig. 47 Checking coolant level
1
Filler neck with cap
2
Overflow
3
Coolant expansion tank
4
Radiator connection hose
5
Coolant level
A
Maximum mark (FULL)
B
Minimum mark (LOW)
1. Open the right-hand access door.
2. Check the level of coolant in the expansion tank.
Top up when the coolant level falls below the minimum level
B
.
3. Close the access door.
Find out and rectify the reason for coolant loss.
10.4.1.2 Check coolant
The coolant should be checked according to the maintenance schedule to ensure quality and opera‐
tional life.
Coolant quality can be determined by the following parameters:
■ Visual check
■ Antifreeze concentration measurement
1. Open the right-hand access door.
2. Unscrew and remove the expansion tank filler cap
1
.
Visual check
The coolant should be checked for its colour and any particles or sediments floating in it.
➤ Take a coolant sample and have analysed.
The coolant should be changed if it is discoloured or has floating particles.
Antifreeze concentration measurement
An instrument (e.g. refractometer) is used to check antifreeze concentration.
10 Maintenance
10.4 Engine
104
Service Manual Screw Compressor
M135 SIGMA CONTROL MOBIL
No.: 9_6975 00 E