HARBEN CENTURY, Service Manual

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Flowplant Century Pump Manual
c. Hold end of tap in a vice and gently tap the face of Mandrel (116) with a nylon mallet,
until the Bush is removed.
d. Carefully press a new Bush into the Mandrel using a drift (part no 201-044).
e. Using a 1.9 mm diameter bit, drill through 6 holes in Mandrel through wall of Bush (see
Fig 4.1 - holes A).
f. Using a 1.9 mm diameter bit, drill through hole in Mandrel, right through Bush (see Fig
4.1 - holes B).
g. Using a flat punch, refit Pin (115) through Mandrel and Bush.
Fig 4.1 Mandrel Assembly
x. To assemble Mandrel assembly (38) and Diaphragm (37), smear a light film of pump
oil along the lobes of the Mandrel then push it into the Diaphragm, ensuring there is
no gap between Mandrel and Diaphragm at inlet end.
Note: It may be easier to hold the Diaphragm with the Mandrel almost pushed home in
one hand, and hit the flat face of a nylon dolly (part no 201-012) with a nylon mallet.
xi. Inspect Seal (82 - Fig 4.1). If it is damaged, replace as follows:
a. Remove and discard old Seal.
b. Insert Dolly (part no 201-061) into the end of the Mandrel.
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