MTU 12V4000M73 series Operating Instructions Manual page 201

2. Open threaded vent plug (1) of the filter to be
flushed.
3. Remove drain valve (2) and drain fuel.
Result: Fuel flows from filtered side back to the unfil-
tered side, flushing the filter deposits down-
wards out of the filter.
4. Close threaded vent plug (1) and drain
valve (2).
5. Open rotary slide valve (2) a little (turning to
approx. 30°) to introduce fuel into the filter
housing with the new filter element.
6. Close vent valves (1) as soon as fuel emerges
from vent pipe (4).
7. Turn the rotary slide valve to the upright posi-
tion (3) until it engages.
Result: Both filters are cut in.
8. Set differential pressure gauge (→ Page 195).
MS150045/03E 2018-08 | Fuel Filter | 199