Gorman-Rupp Pumps T8A71S-B /F,/FM - Manual (Page 38)

OM-05352 SUPER T SERIES
MAINTENANCE & REPAIR PAGE E - 15
in the mounting slot in the suction flange (46). Align
the adaptor with the flange hole, and secure the as­
sembly with the check valve pin (3).
NOTE
If the suction or discharge flanges were removed,
replace the respective gaskets, apply `Permatex
Aviation No. 3 Form‐A‐Gasket' or equivalent com­
pound to the mating surfaces, and secure them to
the pump casing with the attaching hardware.
Back Cover Installation And Adjustment
(Figure 1 and 6)
If the wear plate (22) was removed for replace­
ment, carefully center it on the back cover and se­
cure it with the hardware (25 and 26). The wear
plate must be concentric to prevent binding when
the back cover is installed.
Clearance between the impeller and wear plate is
adjusted using four adjusting screws and locking
collars. There are 18 detents on the I.D. of each
locking collar. Indexing the collars one detent on
the adjusting screws represents approximately
.005 inch (0,13 mm) of wear plate clearance. The
recommended clearance between the wear plate
and the impeller is .010 to .020 inch (0,25 to 0,50
mm).
Replace the back cover O‐rings (23 and 28), and
lubricate them with a generous amount of No. 2
grease. Clean any scale or debris from the contact­
ing surfaces in the pump casing that might inter­
fere or prevent a good seal with the back cover.
USE TWO
OPPOSING
BACK COVER NUTS
TO PRESS
BACK COVER
INTO PUMP
CASING USE TWO REMAINING
ADJUSTING SCREWS AND
LOCKING COLLARS TO
SET FACE CLEARANCE
INDEX COLLARS 3
DETENTS COUNTER‐
CLOCKWISE, THEN
TURN CLOCKWISE
UNTIL SCREW
HOLES ALIGN
Figure 9. Installing and Adjusting Back Cover
Screw the four adjusting screws (43) into the
tapped holes in the back cover plate until they are
just flush with the machined surface on the back
side of the cover plate.
Align the back cover plate over the studs (41) and
slide it into the pump casing. Use two back cover
nuts (42) on diagonally opposing studs to press
the back cover into the pump casing until the wear
plate just touches the impeller when the shaft is
turned by hand. Tighten the back cover nuts
evenly to avoid binding.
With the wear plate just touching the impeller, turn
the two free adjusting screws until they engage the
pump casing. Position the locking collars over the
adjusting screws so the holes in the collars for the
locking screws align approximately with the holes
in the cover plate.
Loosen the back cover nuts used to press the back
cover into the pump casing one full turn.
Pull the collars off the adjusting screws, index them
three detents counterclockwise, and reinstall the
collars on the adjusting screws. Use the collars to
turn the adjusting screws clockwise until the holes
in the locking collars realign with the tapped screw
holes in the back cover plate. Secure the locking
collars to the back cover plate with the hardware
(36 and 37). Install the two remaining back cover
nuts snugly against the adjusting screws.
Remove the first two back cover nuts from their
studs. Turn the adjusting screws clockwise until