The Davey Silensor SLS150 uses a mechanical seal for a 5/8″ shaft, and this CapacitorsNZ seal replaces Davey part 49771SP. The same seal is listed for the Silensor SLS75, SLS100, SLS200, SLS300, SLL150, SLL200, SLL300 and SLL400, and the Davey HS50 and HS60. Measure the shaft or compare your old seal before fitting.
Davey Silensor SLS150 seal part number: 49771SP
Davey’s reference for the shaft seal in the Silensor SLS150 is 49771SP. This is an aftermarket seal made to replace it, for a 5/8″ shaft (about 15.9 mm). The pump label should show the model as SLS150 or SLS150E. If you still have the old seal’s packet or a Davey parts diagram for your pump, the 49771SP number is the quickest way to confirm you are matching like for like.
This seal is also sold on its own as our 5/8″ mechanical seal to suit Davey HS50, HS60, Silensor and ProMaster pumps.
Which pumps use the same seal
The 49771SP seal is listed for these Davey pumps as well: HS50, HS60, Silensor SLS75, Silensor SLS100, Silensor SLS200, Silensor SLS300, Silensor SLL150, Silensor SLL200, Silensor SLL300 and Silensor SLL400. It is also listed for the Davey HS60-08 and Davey ProMaster, which don’t have their own page.
Signs the SLS150 seal has failed
- Drips or a damp patch where the pump housing meets the motor.
- White crusting or rust stains running down below the motor end.
- Air bubbles in the pump basket or the pump struggling to hold prime, which a worn seal can cause.
- A grinding or squealing note from the motor, which can mean water has already reached the bearings.
Fitting notes
A mechanical seal comes in two halves: a stationary seat that presses into the pump housing and a spring-loaded rotating half that slides onto the shaft behind the impeller. Keep the polished faces clean and dry of fingerprints, and use clean water or a little soapy water to ease the parts on, never grease or oil. Press the seat in squarely with even pressure. Before reassembly, check the shaft for scoring or corrosion where the seal sits. Once it is back together, prime the pump and never let it run dry, as running without water, even briefly, can overheat and damage new seal faces.
If the motor has also been slow to start, the Davey Silensor SLS150 service kit pairs this seal with a run capacitor, which is also sold alone as the SLS150 capacitor. Seals for other models are on our Davey service kits page.
Before you order
Check the old part before fitting: match the size of your old seal.
Capacitor details for this pump: Davey Silensor SLS150 capacitor guide.