LINC 86 ver. 04082003 - pn 15107
LINC MILTON ROY • 201 IVYLAND ROAD • IVYLAND PA, 18974 • USA • TEL. 215.441.0800 Page 9
M E T E R I N G P U M P S
E L E C T R I C P U M P
To replace or repair the Suction
and/or Discharge Check Valve:
Two-Piece, fig. 1, items 10 & 13,
fig. 2, items 6 & 17, fig. 5 & 6:
Field repair of check valves
is not recommended. However, if
the checks are to be repaired, the
repairs should be done in a clean
environment that has the necessary
equipment to check the valves for
leakage after they are repaired.
The discharge check valve con-
tains a spring to hold the ball against
the seat. In the suction check valve,
the ball floats freely.
To repair the Check Valves:
1. Separate the two halves for
the check valve (fig. 5 & 6,
items 1 & 4).
2. Replace the o-rings, ball and
spring as required (fig. 5 & 6
items 2, 3, 5 & 6). In the
majority of the check valve
the seat o-ring will be Teflon
(fig. 5 & 6, item 2). This o-
ring may be removed, turned
around and reused if a new
o-ring is not available. During
this procedure, extreme care
should be exercised. The
ball should be "peened" on
the Teflon seat to ensure
proper sealing (fig. 5 & 6,
items 2, 5 & 1).
3. Connect the outlet of the
check valve to an air pres-
sure source and apply 10
psig. Place the inlet of the
check valve into water or
bubble test fluid. If bubbles
appear, reset the ball to the
seat o-ring and retest. In-
crease the air pressure to
100 psig and again check for
leaks as above.
4. Ensure that the proper flow
direction, as marked on the
valve body, is observed
when installing or replacing
the check valve.
5. Install the repaired check
valves into the pump body
and tighten securely.
Optional Bellows Pump Head
86-20 & 86-30
3/8" & 1/2" Plungers:
(figure 2)
To replace the Seals, Split
Bushings & Bellows:
1. Remove the entire bellows
pump head assembly from
the drive housing assembly
as previously described for
the standard pump head
assembly.
2. Loosen the four set screws
(fig. 1, item 4) that mount
the bellows seal body to the
head spacer (fig. 1, items
16 & 17). Pull the head
spacer assembly, with the
plunger attached (fig. 1,
item 8), out of the bellows
seal body. Loosen the six
cap screws (fig. 2, item 13)
that hold the bellows seal
body to the bellows housing
(fig. 2, item 8). Separate
the seal body and housing.
3. The split bushings, the
spacer and seals (fig. 2,
items 14, 15 & 16) can be
removed from the bellows
seal body by pushing the
round shank of a drill bit
through the plunger hole in
the bellows seal body. Use
a 25/64" diameter bit for the
3/8" plunger pump and a
33/64" diameter bit for the
1/2" plunger pump.
Note: Be careful not to scratch
the bore that houses the seals.
4. Remove the bellows (fig. 2
item 10) from the bellows
housing (fig. 2, item 8).
The bellows will be tight in
its housing and may be hard
to remove. Do not dam
age the sealing surfaces
while removing the bellows.
5. To reassemble the pump,
position the bellows hous-
ing in the vertical position,
possibly in a vise. Start by
placing the bellows spring
and bellows (fig. 2, item 9
& 10) in the bellows hous-
ing. Then, install the bel-
lows retainer and o-rings
(fig. 2, items 12, 2, 3, 4, &
5). Lubricate the o-rings be
fore installation.
6. Fill the bellows with 10W-30
or 5W-30 motor oil depend-
ing on temperature condi-
tions using the following
procedure.
7. Slowly fill the bellows cavity
until oil is flush with the top
of the bellows. Air will be
trapped in the bellows con-
volutions.
