Manual

Preassembly inspections
Replacement guidelines
Casing check and replacement
Inspect the casing for cracks and excessive wear or pitting. Thoroughly clean gasket surfaces and alignment
fits in order to remove rust and debris.
• Localized wear or grooving that is greater than 1/8 in. (3.2 mm) deep
• Pitting that is greater than 1/8 in. (3.2 mm) deep
• Irregularities in the casing-gasket seat surface
Impeller replacement
This table shows the criteria for replacing the impeller:
Impeller parts When to replace
Vane edges When you see cracks, pitting, or corrosion damage
Keyway and bores When you see damage
Gaskets, O-rings, and seats replacement
• Replace all gaskets and O-rings at each overhaul and disassembly.
• Inspect the seats. They must be smooth and free of physical defects.
• Replace parts if the seats are defective.
Wear rings or suction sideplate checks
Check the surfaces for pitting, and excessive wear or corrosion damage.
Stuffing box cover and seal chamber replacement
• Thoroughly clean the gasket surfaces and fits to remove rust and debris.
• Inspect surfaces for pitting, and excessive wear or corrosion damage.
Bearing-frame inspection
Checklist
Check the bearing frame for these conditions:
• Visually inspect the bearing frame and frame foot for cracks.
• Check the inside surfaces of the frame for rust, scale, or debris. Remove all loose and foreign material.
• Make sure that all lubrication passages are clear.
• If the frame has been exposed to pumped fluid, inspect the frame for corrosion or pitting.
• Inspect the inboard-bearing bores.
If any bores are outside the measurements in the Bearing fits and tolerances table, replace the bearing
frame.
• Inspect the shafts and sleeves for wear.
• Inspect the labyrinth seal O-rings for cuts and cracks.
Reassembly
Assemble the bearing frame
WARNING:
Do not use a flame to heat bearings. This will damage the bearing surfaces.
1. Install the bearings on the shaft:
Maintenance
Models 3180, 3181, 3185, and 3186 Installation, Operation, and Maintenance Manual 85