Duff-Norton RAM-PAC - Page 9

reseating
ball
seats
A.
B.
C.
The ball
seats, as
supplied by
the
factory,
should last for
years.
However, it
may hap-
pen that
the ball does
not seat
properly be-
cause
of a
piece of
lint,
packing, scale or
a
metal chip
may have
lodged in
the ball
seat.
The proper
procedure to
follow in
checking
a ball
seat is:
Remove ball, spring, and spacer.
Examine the ball very closely for fl ats, nicks
or scratches. If
any fl aw is found, replace the
ball.
Inspect the ball
seat to see if there
are any
foreign
particles lodged in
it. If so, remove
them.
D .
Flush the
unit thoroughly
using a good
clean-
ing
solvent such as:
"AMSCO
TRICHLOR-
ETHYLENE,"
made by the
American Min-
eral Spirits
Company,
Division of
the Pure
Oil Company.
E .
Drain out
the
solvent
and
carefully
examine
the
ball
seat
using a fl
ashlight
to
permit a
close
visual
inspection.
If the
ball seat
is in
good
operating
condition, it
will
show up
as a
very
narrow, ring
-shaped,
shiny
surface
around
the
lip
of the
smaller
hole
against
which the
ball
is
seated.
F.
G.
If the ball seat
appears defective, minor im-
perfections such as indentations can be cor-
rected through reseating.
Drop a new ball into the seat and
reseat it
using a punch and
a 1 / 2
lb.
hammer. One
sharp blow of the
hammer is sufficient. Dis-
card this ball. Use a new ball
for assembly.
H
. Carefully reassemble the
parts in the reverse
manner and bleed the air from the pump
following instruction given under Point 15
of V.
I
• Retest
the ball seat
under
hydraulic
pressure.