Viking Pump TSM161.3: LS-M 127/4127 - Manual (Page 8)

SECTION TSM 161.3 ISSUE D PAGE 8 OF 12
ASSEMBLY
Standard Mechanical Seal
(PTfE fitted Type)
The seal used in this pump is simple to install and good
performance will result if care is taken during installation.
The principle of the mechanical seal is contact between the
rotary and stationary members. These parts are lapped to
a high finish and their sealing effectiveness depends on
complete contact.
A number of heavy-duty pumps are furnished with special
mechanical seals. These special seals are not discussed in
TSM161.3. Information is available by contacting the factory.
When requesting special seal information, be sure to give
pump model number and serial number.
1. Install bracket bushing. If bracket bushing has a
lubrication groove, install bushing with groove at 6:00
o’clock position in bracket. If carbon graphite, Refer to
Installation of Carbon graphite Bushings, page 10.
2. Coat rotor shaft with non-detergent SAE 30 weight oil.
Start end of shaft in bracket bushing and turn from right
to left, slowly pushing until the ends of the rotor teeth are
just below the face of the casing.
3. Using a .015 inch head gasket, install head and idler
assembly on pump. Pump head and casing were marked
before disassembly to insure proper reassembly. If not, be
sure idler pin, which is offset in pump head, is positioned
toward and equal distance between port connections to
allow for proper flow of liquid through pump.
If pump is equipped with jacketed head plate, install at
this time along with new gasket.
Tighten head capscrews evenly.
If pump was equipped with a relief valve and it was
removed during disassembly, install a head with new
gaskets. Relief valve adjusting screw cap must always
point toward suction port. Refer to figures 1 and 2,
page 1. For relief valve repair or adjustments, Refer to
Pressure Relief Valve Instructions, page 10.
5. Tap shaft forward approximately 0.50 inch and remove
pair of half round rings under inner spacer collar. There
is no pair of half round rings on Q, QS and M size pumps.
Refer to figure 7, page 5.
6. Carefully remove rotor and shaft to avoid damaging
bracket bushing.
7. Remove seal holder and seal holder plate.
8. The seal seat and rotary member of the seal can now be
removed from the side opening of bracket.
9. Loosen the four setscrews over the outer and inner
end caps. Remove both end caps, spacer collars and
ball bearing. Refer to figure 4, page 5. The inner end
cap can be removed through the side openings in the
bracket.
10. Clean all parts thoroughly and examine for wear or
damage. Check lip seals, ball bearing, bushing and idler
pin and replace if necessary. Check all other parts for
nicks, burrs, excessive wear and replace if necessary.
Wash bearings in clean solvent. Blow out bearings with
compressed air. Do not allow bearings to spin; turn them
slowly by hand. Spinning bearings will damage race
and balls. Make sure bearings are clean, then lubricate
with non-detergent SAE 30 weight oil and check for
roughness. Roughness can be determined by turning
outer race by hand.
Be sure shaft is free from nicks, burrs and foreign
particles that might damage bracket bushing. Scratches
on shaft in seal area will provide leakage paths under
mechanical seal.
11. Casing can be checked for wear or damage while
mounted on bracket.
fIgURE 6
TAPERED INSTALLATION SLEEVE
SHAfT
MECHANICAL SEAL
ROTARY MEMBER
LEfT SIDE
Of PUMP
SEAL ACCESS HOLE (fOR SETSCREWS)
MECHANICAL SEAL (ROTARY MEMBER)
SEAL SEAT
SEAL HOLDER
SEAL SEAT gASKET SEAL
HOLDER
PLATE
fIgURE 5 - PTfE fITTED MECHANICAL SEAL