Ampco Pumps Company LF 401, Instruction & Maintenance Manual

Page: 30 / 36

30
SETTING THE IMPELLER CLEARANCE
Assemble the pump as described in the Pump Assembly and Seal Installa-
tion section of this manual. For double seals perform steps 1-10 and for single
seals perform steps 4-10 of the Pump Assembly and Seal Installation instructions.
Take note that the shaft collar screw must be torqued to the proper torque value as
determined by the frame size of the motor. Using a torque value less than the pre-
scribed value may allow the shaft to move toward the cover and cause damage to
the pump.
·0.02” (0.5mm) Shim for LF R Pumps
·0.04” (1.0mm) Shim for LF V Pumps
·0.06” (1.5mm) Shim for LF X Pumps
·0.08” (2.0mm) Shim for LF 401 Pumps
1. Loosen the socket head cap
screw in the shaft collar and re-
tighten it just enough so the shaft is
still able move along the motors
axis.
2. Once the shaft collar is able to
slide on the motor shaft, insert an
appropriate thickness shim between
the back side of the impeller vane
and the back of the casing’s bore as
shown in figure 38. Check all vanes
and set the clearance with the vane
that has the smallest clearance.
LF & LM SERIES PUMPS
Figure 37
Figure 38