Documents are only to be used and distributed completely and unchanged. It is strictly the users’ responsibility to check carefully
the validity of this document with respect to his product. Manual-no.: 999155 / 29/01/2009
page 25 of 36
☞
ME 8 NT / MD 4 NT / MV 2 NT
: Underneath the pump there is a connecting tube (MV 2 NT: with con-
necting block) between the two housing covers. The connecting tube is merely stuck into the housing
covers and sealed with seal rings at the connecting tube’s ends. If the housing cover is removed, the
connecting tube becomes detached as well.
Replacing the diaphragm
Replacing the diaphragms of a pump MZ 2D NT:
☞
Check the diaphragm for damage and replace if necessary.
➨
Use a Phillips screw driver to remove the countersunk head screw in the centre of the diaphragm
clamping disc.
☞
Attention:
The screw is secured with adhesive against loosening. Clean the screw or use a new
one (cat. no.: 63 98 47).
☞
If the old diaphragm is difficult to separate from the support disc, immerse the assembly in naph-
tha or petroleum ether. Do not inhale!
➨
Check for washers between the diaphragm support disc and the connecting rod.
Do not mix the
washers from different pump heads
. Make sure that the original number is reassembled at the
individual pump head.
☞
Smaller number of washers: The pump will not attain ultimate vacuum. More washers: The clamp-
ing disc will hit the head cover; noise or even blockade and damage of the pump.
☞
Attention:
Double diaphragm consisting of two single dia-
phragms! Put the two diaphragms together with the printed
sides outwards.
➨
Apply a drop of adhesive (OmniFit
®
50M or Loctite
®
243) to
the lower side of the screw head and the thread and screw
diaphragm clamping disc, diaphragm, diaphragm support
disc and washers (if applicable) to connecting rod.
OmniFit
®
and Loctite
®
are registered trade marks of Henkel Technologies
Replacing the diaphragms of pumps ME 4 NT, MZ 2(S) NT, ME 8 NT, MD 4 NT, MV 2 NT:
☞
Check the diaphragm for damage and replace if neces-
sary.
➨
Lift the diaphragm carefully sidewise.
☞
Never use a spiky or sharp-edged tool to lift the dia-
phragm.
➨
Use the diaphragm key to grip the diaphragm support disc
under the diaphragm. Unscrew the diaphragm support
disc with diaphragm and diaphragm clamping disc.
☞
If the old diaphragm is difficult to separate from the support
disc, immerse assembly in naphtha or petroleum ether. Do
not inhale!
➨
Check for washers between the diaphragm support disc
and the connecting rod.
Do not mix the washers from
the different pump heads
. Make sure that the original
number is reassembled at the individual pump head.
☞
Smaller number of washers: The pump will not attain ulti-
mate vacuum. More washers: Clamping disc will hit head
cover; noise or even blockade and damage of the pump.
