Viking Pump TSM151.1: H-LL 123/4123 - Manual (Page 11)

SECTION TSM 151.1 ISSUE C PAGE 11 OF 13
THRUST BEARING ADJUSTMENT
1. Loosen setscrews over outer and inner end caps.
Two for H and HL size pumps, four for all other
sizes.
2. Turn inner end cap clockwise, viewed from shaft
end, until it projects slightly from bracket exposing
approximately three threads.
3. Turn outer end cap clockwise until rotor is tight
against head and rotor shaft cannot be turned.
4. Make a reference mark on bracket end, opposite a
notch on outer end cap. Back off outer end cap
required number of notches. See Figure 14.
Each 0.25 travel on circumference of end cap is
equivalent to approximately .0115 inch for all sizes.
5. End clearances set per Step 4 are adequate for
viscosity’s up to 750 SSU (SAE 20-lube oil at room
temperature). Higher viscosity liquids require
additional end clearances.
As a general guideline, for viscosity’s between 750
and 7500 SSU (heavier lube oils) double the amount
of end clearance indicated in Step 4; for viscosity’s
between 7500 and 75,000 SSU (e.g., resins) triple
the amount an for viscosity’s greater than 75,000
SSU (e.g., black strap molasses) use 4 times the
amount.
6. Tighten inner end cap with a spanner wrench. Tap
spanner wrench lightly but DO NOT OVER
TIGHTEN, as it will damage the threads.
7. Tighten setscrews that hold inner and outer end
caps to prevent their turning in bracket.
8. Rotor and shaft should turn smoothly by hand one
complete revolution. If rotor and shaft doesn’t turn
smoothly, go back and repeat Thrust Bearing
Adjustment Steps 1 through 8.
INSTALLATION OF CARBON
GRAPHITE BUSHINGS
When installing carbon graphite bushings, extreme care
must be taken to prevent breaking. Carbon graphite is a
brittle material and easily cracked. If cracked, the bushing
will quickly disintegrate. Using a lubricant and adding a
chamfer on the bushing and the mating part will help in
installation. The additional precautions listed below must be
followed for proper installation.
1. A press must be used for installation.
2. Be certain bushing is started straight.
3. Do not stop pressing operation until bushing is in proper
position, starting and stopping will result in a cracked
bushing.
4. Check bushing for cracks after installation.
Carbon graphite bushings with extra interference fits are
frequently furnished for high temperature operation. These
bushings must be installed by a shrink fit.
1. Heat bracket or idler to 750 º F.
2. Install cool bushings with a press.
3. If facilities are not available to reach 750º F.
temperature, it is possible to install with 450º F.
temperature; however, the lower the temperature, the
greater the possibility of cracking bushing.
Consult factory with specific questions on high temperature
applications. Refer to Engineering Service Bulletin ESB-
3.
Pump
Size Turn Outer End Cap C.C.W.
No. of Notches* Or Length on O.D., Inches
H – HL 3 0.50
K - LL 3 0.656
*Each small notch on outer end cap represents .001 inch
end clearance