Gorman-Rupp Pumps 14D1-GX390 1142746 thru 1325667 - Manual (Page 26)

OM−04529 10 SERIES
MAINTENANCE & REPAIR PAGE E − 9
A clearance of .020 to .040 inch (0,51 to 1,02 mm)
between the impeller and the intermediate is nec-
essary for maximum pump efficiency. Measure this
clearance and add or remove impeller shims until
this clearance is reached.
Pump Casing Installation
(Figure 2)
Install the same thickness of pump casing gaskets
(8) as previously removed and secure the pump
casing (1) to the intermediate with the nuts (14). Do
not fully tighten the nuts at this time.
A clearance of .008 to .015 inch (0,20 to 0,38 mm)
between the impeller and the wear plate is also rec-
ommended for maximum pump efficiency. Install
the back cover and set this clearance by adding or
removing gaskets in the pump casing gasket set
until the impeller scrapes against the wear plate
when the shaft is turned. After the impeller scrapes,
add approximately .015 inch (0,38 mm) of gaskets
and fully tighten the nuts (14).
NOTE
An alternate method of adjusting this clearance is to
reach through the discharge port with a feeler
gauge and measure the gap. Add or subtract pump
casing gaskets accordingly.
See Figure 1 and secure the pump casing to the
base (3) with the hardware (12, 13, 14 and 15). Be
sure to reinstall any leveling shims used under the
mounting feet of the pump casing.
Back Cover Installation
(Figure 2)
Inspect the wear plate (15) and replace it if badly
worn or grooved. Install the wear plate on the back
cover using the hardware (16 and 17).
Clean any scale or debris from the back cover
shoulder and pump casing which might prevent a
good seal.
NOTE
Apply a film of ‘Never-Seez’ or equivalent com-
pound on the back cover shoulder or any surface
which contacts the pump casing to ease future dis-
assembly and to reduce rust and scale build up.
Replace the back cover gasket (19) and slide the
back cover assembly (23) into the pump casing.
Be sure the wear plate does not scrape against the
impeller.
Secure the back cover assembly to the pump cas-
ing using the hardware (21 and 22). Do not over
tighten the wing nuts; they should be just tight
enough to ensure a good seal at the back cover
shoulder.
Suction Check Valve Installation
(Figure 2)
Inspect the check valve components and replace
as required. Subassemble the check valve weights
(30 and 33) and check valve gasket (34) with the
hardware (31 and 32).
Position the check valve assembly (29) in the suc-
tion port with the large weight (33) facing toward
the inside of the pump casing. Install the suction
flange (35) and secure with the nuts (28). Check
the operation of the check valve to ensure proper
seating and free movement.
Final Pump Assembly
(Figure 1)
Be sure the pump and engine are securely
mounted to the base.
Install the suction and discharge lines and open all
valves. Make certain that all piping connections are
tight, properly supported and secure.
Be sure the engine has been properly lubricated,
see LUBRICATION.
Remove the fill plug assembly (4). Fill the pump
casing with clean liquid. Reinstall the fill plug and
tighten it.
Refer to OPERATION, Section C, before putting
the pump back into service.