MTU 12V4000G34F Operating Instructions Manual page 168

2. Undo threaded vent plugs (2, 3) unscrewing
at least one rotation.
Note: • Only operate the fuel priming pump man-
ually!
• Move the pump plunger only vertically to
avoid damaging the pump!
3. Unlock fuel priming pump, screw out han-
dle (1).
Note: Catch escaping fuel with a suitable rag.
4. Operate fuel priming pump handle (1) until
bubble-free fuel emerges from the threaded
vent plugs (2, 3).
Note: Never actuate the handle with the threaded
vent plugs closed!
5. Move handle (1) of fuel priming pump back
and screw in.
6. Close threaded vent plugs (2, 3) and tighten
by hand.
Venting fuel prefilter in case of
high pressure, version B
1. Open fuel supply as necessary.
2. Carefully undo threaded vent plugs (1) un-
screwing at least one rotation.
3. Leave threaded vent plugs (1) opened until
bubble-free fuel emerges at the vent plugs.
4. Close threaded vent plugs (1) and tighten by
hand.
168 | Fuel Filter | MS15060/01E 2018-12