MTU 16V4000M*3 series Operating Instructions Manual page 233

Filling coolant through filler
neck
1. Open vent points on charge-air cooler, ex-
haust turbochargers and on plate-core heat
exchanger (arrows).
Note: On engines with a separate heat exchanger,
the expansion tank is connected separately
from the engine to the external cooling sys-
tem.
2. Fill in engine coolant via filler neck on expan-
sion tank until engine coolant level remains
constant at top edge of filler neck.
3. When coolant emerges from the vent points,
close vent points one by one, proceeding
from the lowest point upwards.
4. Check proper condition of breather valve and
clean sealing faces if required.
5. Set breather valve onto filler neck and turn
until the first stop.
6. Start engine (→ Page 96).
7. After 10 seconds of running the engine with-
out load, shut down the engine (→ Page 98).
8. Turn breather valve counterclockwise and re-
move.
9. Check coolant level (→ Page 225) and top up
engine coolant as required:
a) Repeat the steps from starting the en-
gine (→ Step 6) until no coolant needs to
be topped up any more.
b) Check proper condition of breather valve
and clean sealing faces if required.
c) Position breather valve on filler neck and
close.
Final steps
1. Start the engine and run it without load for some minutes.
2. Check coolant level (→ Page 225) and top up engine coolant as required.
MS15035/00E 2018-08 | Coolant Circuit, General, High-Temperature Circuit | 231