National Vacuum Equipment 607 challenger series Replacement And Rebuild Manual - page 13
607 Challenger
Series | 13
www.natvac.com | 800.253.5500
12 Remove the four-way
assembly, gaskets, and check
valve assembly Carefully turn
the housing upside down so
that the pump feet are facing
the ceiling
13 Inspect the housing for wear or damage If the housing needs
to be bored or honed, remove only as much material as is
necessary to give a smooth clean bore
The maximum overbore we recommend is 0 060 inches A new
housing has a bore of 7 875 inches
If you bore or hone the housing, remove all connected accessories,
including the fan shroud, 4-way valve, gaskets, etc
14 Clean the housing of any
debris and apply a liberal
amount of lubrication to the
housing bore
15 (Optional) If there is damage
evident to the bearings, they
will need to be replaced Once
the rotor is removed, start
by cutting off the old bearing
inner race on both ends of the
rotor Be sure to line up the
cutting wheel with one of the
vane slots so as not to dam-
age the rotor or seal sleeve