MTU 12 V 4000 M23F Operating Instructions Manual page 240

Filling coolant through filler
neck
1. Open vent points on charge-air cooler, ex-
haust turbochargers and on plate-core heat
exchanger (arrows).
2. Fill coolant through the filler neck of the
expansion tank (for engines with remote
heat exchanger: the expansion tank is part
of the remote cooling system) until the
coolant level at the top edge of the filler
neck remains constant.
3. When coolant emerges from the vent
points, close vent points one by one, pro-
ceeding 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 77).
7. After 10 seconds of running the engine
without load, shut down the engine
(→ Page 86).
8. Turn breather valve counterclockwise and
remove.
9. Check coolant level (→ Page 234) 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 re-
quired.
c) Set breather valve onto filler neck and
close it.
Final steps
1. Start the engine and run it without load for some minutes.
2. Check coolant level (→ Page 234) and top up engine coolant as required.
240 | Task Description | MS150068/01E 2014-01