The Motor Killer
It's when you notice water puddling under the pool motor. Unless it's been raining, the water is evidence of one of three increasingly serious problems:
A leaky pump seal. You may or may not see water dripping from the bottom of the pump body; some pumps sit directly on the slab. An aggravating problem only because when the pump's off, air is allowed to slip into the system making priming a chore. Never an emergency repair, but easy enough to fix.
A leak at the PVC male adaptor on the top of the pump. Run your finger around the seam where PVC pipe joins the pump body. Running water here is not a mortal wound but a repair that needs attention because the male adaptor will eventually separate completely and water will spew out of the pump and straight up into the air.
A leaky shaft seal. This is the motor killer and is evidenced (right) by water dripping out of the air vents on the bottom front of the motor. What's happened is that the shaft seal has failed and water is migrating down the motor shaft and into the motor.
Water erodes grease in motor bearings and you will first be alerted to the damage when motor bearings start whining. The whine will turn into a screech and finally the bearings will meld in place and the motor won't turn at all. Your local pump wholesaler will recognize the cause of this damage and negate any warranty.
Open the pump. A Sta-Rite type pump is held together with a large stainless steel band and a Hayward type pump is opened by undoing either 4 or 6 - 9/16 bolts. The good news, you'll have the opportunity to teflon-grease all rubber gaskets and threads to greatly extend the life of your pump.
(photo, left) Remove a plastic diffuser (black snap-on or white with eight tiny screws) and you'll find the impeller. Always inspect the front center of the impeller for a screw or bolt holding impeller to end of the shaft. It's a rare feature but can save you from breaking the impeller when you're simply trying to remove it.
To immobilize the shaft, any good motor repairman will tell you to remove the end cap, press the wiring aside and use either a screwdriver (Hayward) or open-end wrench (Sta-Rite) to secure the shaft end. But, this can add 15 to 20, not always happy minutes to your job.
An old school tech trick is to immobilize the shaft by gently inserting a long, thin screwdriver through an air vent (note the screwdriver handle in the photo, left), firmly resting the tip against the cooling fan blades. Break a blade and you'll throw a motor that turns better than 4,000 revolutions a minute out of balance, but I haven't broken a blade in 30 years of using this procedure. Everything is plastic and everything is breakable. If you need channel locks to loosen the impeller, use a rag to cushion the jaws. Be firm but always, always with respect.
(right) Remove the impeller and a shaft seal pops into view. Undo the either 4 or 6 bolts that hold housing to motor. Then, with a 'bump' the pump housing should pull easily away from the motor.
Often, the rubber seal will hang up in the pump housing recess. I use a 9/16" socket to gently bump it out of position. Clean the recess with a clean rag or paper towel.
Avoid touching the white teflon surface. By this point in the repair, your fingers are dirty enough to contaminate the teflon surface, greatly reducing its service life. Use a little waterproof grease to lubricate the rubber edges of the seal (old techs use spit) and using your rag, press the seal tightly into place. Despite all your care should you notice a fingerprint on the teflon, use your rag and a little waterproof grease to clean it.
The brown ceramic edge of the shaft seal rides against the teflon and should also be wiped clean. The steel edge of the seal will soon butt up against the back of the impeller. If the impeller has a trumpet type projection (ie Hayward MaxFlo and SuperFlo), it's easiest to slip the seal over the trumpet end before you thread it onto the shaft.
It's not necessary to apply anymore than hand pressure to tighten the impeller as torque will hold it in place. Assemble the pump in reverse order, greasing every rubber gasket and threaded fitting as you go. Fill the strainer basket with water to prime the pump, turn the motor on to check for leakage or odd noises and you're done.
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