Specifications Information and Repair Parts Manual
4294-98 thru 429N-98
4294-251-00
2
9/2016
1-Inch Self-Priming Centrifugal Pumps
SHIM ADJUSTMENT
When installing a replacement impeller (Ref. No. 11) or motor (Ref. No. 1), it
may be necessary to adjust number of shims (Ref. No. 10) to ensure proper
running clearance between impeller and casing. Proceed as follows:
NOTE:
A proper running clearance is less than 0.010.
1. For impeller replacement, add one 0.010” shim in addition to shims
removed originally.
2. For motor replacement, add two 0.010” shims in addition to shims
removed during disassembly.
3. Reassemble pump using “Mechanical Seal Replacement” for reference.
IMPORTANT:
Be sure that casing is in place and check shaft to make sure
it is turning freely (use screwdriver slot or two flats at rear of motor to turn
shaft). If it turns freely, check to ensure that casing cover and casing are fitted
metal-to-metal where they meet on outside. If they are not metal-to-metal,
tighten the hex nuts (Ref. No. 4) and recheck shaft for free turning. Tighten,
carefully turning shaft while tightening so that motor bearings are not damaged
in event that too many shims were installed. If shaft seizes before fasteners
are completely tight, disassemble pump and remove one shim and repeat
reassembly.