MTU 20 V 4000 M93 x Operating Instructions Manual page 162

Filling with coolant through filler neck
1. Fill coolant through filler neck on expansion tank until coolant emerges from the loosened unions at the
coolant distributor.
2. Tighten the union for coolant line at the coolant distributor (→ Page 155).
3. Continue to fill until coolant level remains constant at top edge of filler neck.
4. Tighten the coolant line union on both turbochargers (→ Page 155).
5. Check proper condition of breather valve and clean sealing faces if required.
6. Start engine with open expansion tank (→ Page 58) and operate it at idle.
7. Open vent points successively, starting at the lowest point and proceeding upwards. Wait until air no
longer emerges from the vent points and close them.
8. Top up coolant in expansion tank until coolant level is at the overflow edge.
9. When coolant temperature is 40°C (T-Coolant), increase engine speed to 1,000 rpm for approx. 2 mi-
nutes. With the engine running idle, top up with coolant until coolant level is at the overflow edge.
10. Start engine with open expansion tank and run it up to nominal speed (full load).
11. Operate engine at idle for approx. 5 minutes until coolant temperature is steady. Check coolant level in
expansion tank. If coolant level is above 50%, close filler neck cover. If the coolant level in expansion
tank is less than 50%, stop engine (→ Page 70) and fill coolant into expansion tank until coolant level is
at the overflow edge.
12. Close breather valve on expansion tank and briefly run up engine to full load.
13. Stop engine (→ Page 70).
14. Allow the engine to cool down, then top up with coolant until coolant level is at the overflow edge.
Close breather valve on expansion tank.
162 | Task Description | MS150048/04E 2013-07