The Pedrollo PKM90 bearing set is a matched pair of sealed ball bearings for the motor: one for the drive end next to the pump and one for the fan end. Fit both together when the PKM90 motor gets noisy or the shaft feels rough. Compare your old bearings with these before pressing the new ones on.
Why both Pedrollo PKM90 motor bearings are changed together
The motor shaft of this single-phase peripheral pump runs in two bearings, one at each end. They have done the same hours under the same load, so when one is worn the other is rarely far behind. Getting at either of them means taking the motor apart and pulling the rotor out, so replacing the pair in one go saves doing the whole strip-down twice.
Both bearings in this set are sealed, which keeps grease in and dust and moisture out. Sealed bearings like these are pre-greased and are not regreased once fitted.
Signs the PKM90 motor bearings are worn
Bearing noise usually starts quietly and builds. Listen to the motor with the pump running and then spin the shaft by hand with the power isolated.
- A rumble, growl or rising whine from the motor rather than the pump end.
- The shaft feels notchy, gritty or loose when turned by hand.
- The motor running warmer than it used to.
- Noise that began after a seal leak let water track along the shaft.
Before you strip the PKM90 motor
Worn motor bearings are often the result of a leaking seal that let water into the motor. If water has reached the motor on your PKM90, change the PKM90 mechanical seal at the same time or the new bearings will go the same way. The PKM90 service kit bundles the bearings with the seal and capacitor. Use a proper bearing puller and press on the inner race only when fitting, never tap on the outer race or the seals. Bearings and kits for other Pedrollo pumps are listed under Pedrollo service kits.
Before you order
Check the old part before fitting: match the bearings in your old motor.
Capacitor details for this pump: Pedrollo PKM90 capacitor guide.