Draining coolant, filling in - Anti-freeze table - RA20001200100X(20-0100)
Preceding work:
Bottom engine compartment panel removed
(Maintenance Manual 6190).
Operation no. of the operation texts and work units or standard texts and flat rates
20-1142-1151
| Cap (1) | turn counter-clockwise to detent 1, release pressure. Cap (1) must not be opened unless coolant temperature below 90 °C. Risk of scalding! |
| Cap (1) | turn on to detent 2 and remove. |
| Draining coolant from radiator Hose (inner dia. 12 mm) onto the connection (arrow) |
fit. |
| Drain plug (4) | open, close. |
| Coolant | drain into a suitable vessel (approx. 10 liters). |
| Draining coolant from crankcase | unscrew, screw on (30 Nm). |
| Drain plug (4) with seal next to left and right engine carrier |
NOTE:
Model 129 for drain plug (4) on right side of engine: unbolt shield above steering Model 140 for drain plug (4) on left side of engine: remove exhaust system (49-0045, 49-0170):
|
| Coolant | drain into a suitable vessel (metal tray). |
| Pouring in coolant, bleeding | pour in up to separation level (arrow) on top |
| Coolant | part of expansion reservoir (black) and bottom part of expansion reservoir (transparent). |
| Heater | switch on. |
| Engine | warm up at moderate speed until coolant thermostat opens. |
| Vehicles with stationary heater: stationary heater | bleed (BLEEDING COOLANT CIRCUIT WITH AUXILIARY HEATER - RA83001401165X(1165) ). |
| Coolant | top up up to separation level (arrow) between top part of reservoir (black) and bottom part of reservoir (transparent). |
| Filler neck of expansion reservoir (2) | seal as of a coolant temperature of approx. 60 - 70 °C. |
| Coolant | test for resistance to low temperature. |
| Cooling | system check for leaks Testing cooling system for leaks . |
| Drain plug of radiator (reference value) | 1.5 |
| Drain plug of crankcase | 30 |
| Anti-freeze tester | e.g. | Ph. Gather |
| Prestone-VV-Check (Union Carbide) | 4020 Mettman | |
| Model | Engine | Cooling system with heater | Anti-corrosion | Anti-freeze |
|---|---|---|---|---|
| -37 °C (50 % by vol.) | -45 °C (55 % by vol.) | |||
| 129 | 120.981 | 15.5 | 7.75 | 8.75 |
| 140 | 120.980 | 18.5 | 9.25 | 10.25 |
50 % by vol. water (Mercedes-Benz Specifications for Service Products).
50 % by vol. anti-corrosion/anti-freeze agent (Mercedes-Benz Specifications for Service Products).
A higher concentration is only of practical benefit at lower ambient temperatures.
55 % by vol. anti-corrosion/anti-freeze agent offer anti-freeze protection down to approx. -45 °C.
More than 55 % by vol. anti-corrosion/anti-freeze agent reduces the anti-freeze protection and impairs heat dissipation.
Checking coolant during operation
Before the start of the cold season the coolant should be checked for its resistance to low temperatures.
In countries with high outside temperatures, check the anti-corrosion/anti-freeze agent concentration once a year.
Anti-corrosion protection in the coolant is reduced during operation. Such coolants have a strongly corrosive effect.
The maximum permissible period of use of the approved coolant in a car engine is 3 years . When topping up (after loss of coolant) it is essential to ensure that the anti-corrosion/antifreeze agent concentration in the coolant is 50 % by vol. (anti-freeze protection down to -37 °C).
Before adding fresh coolant, the cooling and heating system must be free of used coolant and of corrosion residues. For this reason, clean cooling and heating system.
Disposing of coolants
The anti-corrosion/anti-freeze agents approved in the Mercedes-Benz Specifications for Service Products are bio-degradable substances.
Observe legal provisions as well as local waste water regulations.
Workshops in Germany should refer to the Environmental Protection Catalogue available from MBVD/PWU.
Anti-corrosion/anti-freeze agent
The anti-corrosion/anti-freeze agent performs the following tasks:
- provides adequate corrosion and cavitation protection for all components
- provides anti-freeze protection
- increases the boiling point
Use only approved anti-corrosion/anti-freeze agents (see Mercedes-Benz Specifications for Service Products).
Water
Use water which is clean and not too hard. Drinking water frequently, but not always, meets requirements. The contents of resolved substances in the water maybe of importance for the occurrence of corrosion. If the water quality is not known, distilled or demineralised water should be used. For water quality see Mercedes-Benz Specifications for Service Products.