OM−05267
SUPER T SERIES
MAINTENANCE & REPAIR
PAGE E − 13
Back Cover Installation And Adjustment
(Figure 1)
If the wear plate (13) was removed for replace-
ment, carefully center it on the back cover and se-
cure it with the hardware (15 and 16). 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 (32) and
locking collars (31). There are 18 detents on the
I.D. of each locking collar. Indexing the collars one
detent on the adjusting screws represents approxi-
mately .005 inch (0,13 mm) of wear plate clear-
ance. The recommended clearance between the
wear plate and the impeller is .010 to .020 inch
(0,25 to 0,50 mm).
USE TWO
OPPOSING
HAND NUTS
TO PRESS
BACK COVER
INTO PUMP
CASING
USE TWO REMAINING
ADJUSTING SCREWS
AND LOCKING COL-
LARS TO SET FACE
CLEARANCE
INDEX COLLARS 3
DETENTS COUNTER-
CLOCKWISE, THEN
TURN CLOCKWISE
UNTIL SCREW
HOLES ALIGN
Figure 6. Installing and Adjusting Back Cover
Replace the back cover O-rings (14 and 18), 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.
Screw the four adjusting screws (32) 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 (33) and
slide it into the pump casing. Use two hand nuts
(28) 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 hand 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 hand 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
(29 and 30). Install the two remaining hand nuts
snugly against the adjusting screws.
Remove the first two hand nuts from their studs.
Turn the adjusting screws clockwise until they en-
gage the pump casing. Install the locking collars
and hardware (29 and 30). Reinstall the hand nuts.
PRESSURE RELIEF VALVE
MAINTENANCE
(Figure 1)
The back cover is equipped with a pressure relief
valve (23) to provide additional safety for the pump
and operator (refer to
Liquid Temperature And
Overheating
in
OPERATION
).
It is recommended that the pressure relief valve as-
sembly be replaced at each overhaul, or any time
the pump overheats and activates the valve.
Never
replace this valve with a substitute which has not
been specified or provided by the Gorman-Rupp
Company.
Periodically, the valve should be removed for in-
spection and cleaning. When reinstalling the relief
valve, apply ‘Loctite Pipe Sealant With Teflon No.
592’, or equivalent compound, on the relief valve
threads. Position the valve as shown in Figure 1
with the discharge port pointing down.
