Pool Pump Parts: All You Need to Know

pool pump parts
Mark Garcia February 11, 2014


All About Pool Pump Parts

All About Pool Pump Parts

The pool pump is the workhorse of the equipment pad - pulling the water from the pool and pushing it through your filter and heater. And when the pool pump ain't working - ain't nothing working!

When we get orders for pool parts here at poolcenter, they are automatically triaged by our system to a priority status. That's because pool pump parts can be very urgently needed.

Understanding the parts of your pool pump is simple enough, and that is the goal of this blog post. Let's start by breaking down the typical parts of a pool pump, with some typical problems and solutions.

Hair & Lint Pot (8)

Also known as the strainer potthe hair and lint pot has a pump basket (9) acting as a pre-filter for the pump, to strain out particles that would clog the impeller. The strainer pot must be air tight for the pump to work properly, and when it is, the pump basket is under a vacuum, so any small void in the works will suck in air, eventually causing the pump to lose prime. There are four areas that this could occur - where the pipe enters the hair & lint pot, and on the opposite side where the pot bolts (17) to the volute (6). Air can also leak from the o-ring (7) that fits around the pump lid (10), and through a loose drain plug (5), or one that is missing an o-ring (21). Water left inside a hair & lint pot during freezing weather will almost certainly crack the hair & lint pot.

Volute (6)

Also known as the impeller housing, the volute is designed to create pressure by diffusing the water as it is thrown out of the impeller (4) vanes. Some pool pumps also use a diffuser, (shown right) also known as an impeller shroud, which helps to increase pressure further on high head pumps. The volute also requires an air tight connection on all sides, to prevent air and water leaks. Air leaks on the front if the connection to the hair & lint pot is loose, and water leaks to the rear, if the connection to the seal plate (12) is loose, or if the drain plug on the bottom or the pipe carrying water out of the volute, is loose.

Seal Plate (12)

The seal plate makes a seal against the volute, with the assistance of the seal plate o-ring (11), and the clamp band (3), or sometimes with a set of nuts and bolts. Loosening the clamp knob (16) allows one to "crack the case", or open up the pump to inspect the impeller (4), and remove the motor from the 'wet end' of the pump. The seal plate also holds the smaller half of the shaft seal (14), press-fit into the center of the seal plate. The motor bolts to the back of the seal plate with the motor shaft extending through the seal plate. The other half of the shaft seal (2) is installed onto the motor shaft, and the impeller threads onto the end of the shaft. The longer motor bolts (19) run through the motor support bracket (1).

Pump Motor (13)

The electric motor has a particular horsepower, voltage and service factor. It also has a particular flange type, either square or round on the shaft end. A slinger (18) comes with the motor, a small rubber gasket that rides on the shaft to sling away any water that makes it past the shaft seal. On the back cap of the motor is a 3/4" hole that allows you to thread in a wire connector, to bring the wires into the motor. Also in the rear of the motor are parts such as the capacitor, a centrifugal switch and the terminal board, where the wires connect.

Pool Pump Troubleshooting Guide

  1. IF your pump is leaking AIR - look for the problem around the Hair & Lint Strainer.
  2. IF your pump is leaking WATER - look for the problem to be in the Volute or Seal Plate.
  3. IF your pump sounds like a SCREECH owl, the motor bearings are shot - rebuild or replace the motor.
  4. IF your pump sounds like it's Gargling ROCKS, it is starved for water, look for obstructions or closed valves.
  5. IF your pump is overheating, check the motor air vents have adequate air flow, and voltage is correct +/- 10%.
  6. IF your pump is not pumping water, check for an air leak first, then inspect the impeller for damage or clogs.


Thanks for Reading!
Mark Garcia