Pioneer PB Series, Operation & Maintenance Manual

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screw if necessary. Use the impeller removal tool to fix the shaft from rotating, and use a metal
bar or piece of wood to rotate the impeller counter-clockwise until it is free of the shaft. It may
be necessary to pound the bar with a hammer to loosen the impeller. Inspect the impeller and
replace as necessary. Use caution when removing the impeller.
BACK WEAR PLATE (P10B)
With the rotating assembly out of the volute and the
impeller removed, remove the four (4) nuts to remove the
back wear plate. Replace the wear plate if it is badly worn
or scored.
MECHANICAL SEAL
With the rotating assembly out of the volute and the impeller removed, slide the shaft sleeve
and rotating portion of the seal off of the shaft as one unit (3” to 8” pumps). On the P10B there
is no sleeve or sleeve o-ring. Drain the oil in the seal cavity by removing the seal cavity drain
plug, located on the bearing housing’s bottom front boss (figure 4)
. Clean and replace the drain
plug after draining seal cavity of oil. Remove the seal housing from the bearing frame, and
place it, face down, on a flat surface. With a suitable tool press on the backside of the
stationary seat until it is removed from the seal housing. On the P10B, the stationary seat is
held in a retainer, and the two are pressed out together.