U.S. Seal PS-851 Seal Assembly In stock$11⁹⁹

U.S. Seal PS-851 pump shaft seal assembly

U.S. Seal PS-851 Seal Assembly

Name: U.S. Seal PS-851 Seal Assembly
Brand: US Seal
SKU: USS-60-5016
Price: 11.99 USD
Availability: InStock

Ask a questionMPN PS-851

$11⁹⁹

In stock

Get volume pricing Request a quote

30 day returns · Easy, with prepaid labels provided

Quick overview

Matched set The rotating half and the ceramic seat come together, so both faces are replaced as a pair.
Two part numbers, one part Listed as PS-851 and also as PS851B.
The part that stops a leaking pump A dripping motor end on a running pump is almost always the shaft seal.
Replace it whenever the pump is open The seal faces bed in together and should not be reused once separated.
Never run dry Seals fail fast when a pump loses prime, so fix the air leak before fitting a new one.
Standard rebuild item The seal goes in alongside the gaskets and o-rings on any pump service.

Full description and specifications ↓

Need a hand?

Bilingual support from pool professionals.

(888) 751-8084Call Chat with a techChat Email usEmail

Frequently bought together

Current item Select U.S. Seal PS-851 Seal Assembly

US Seal

U.S. Seal PS-851 Seal Assembly

$11⁹⁹

Select

US Seal

U.S. Seal PS1000 Shaft Seal Assembly

$6⁹⁹

Select

US Seal

U.S. Seal PS200 Mechanical Seal Assembly

$12⁹⁹

Select

US Seal

U.S. Seal Pump Shaft Seal Assembly PS201

$6⁹⁹

Select

US Seal

U.S. Seal Heavy Duty Mechanical Seal Assembly (PS200), PS-3867

$15⁹⁹

Select

US Seal

U.S. Seal Heavy Duty Seal Assembly, PS-3868

$19⁹⁹

Select

US Seal

U.S. Seal Mechanical Seal, 13/16" ID (Generic), PS-4231

$25⁹⁹

Subtotal

Similar products

Other products people compare with this one.

SuperPro 201 pump shaft seal assembly for 3/4 inch shaft motors

SuperPro 201 Seal Assembly for 3/4" Shaft Motors$11⁹⁹

U.S. Seal PS100 replacement pump shaft seal assembly

U.S. Seal PS100 Replacement Pump Seal Assembly$6⁹⁹

U.S. Seal PS-2131 pump shaft seal assembly

U.S. Seal Shaft Seal Assembly PS2131$15⁹⁹

Aladdin GO-KIT 71 seal kit for the old style Polaris PB4-60 booster pump

Aladdin GO-KIT 71 Seal Kit for Polaris PB4-60 Booster Pump$16⁹⁹

Pentair 351446 WhisperFlo XF seal plate o-ring

Pentair WhisperFlo XF Seal Plate O-Ring, 351446$12⁹⁹

Pentair 357102 molded seal plate gasket in almond for WhisperFlo pumps

Pentair Molded Seal Plate Gasket for WhisperFlo, 357102$6⁹⁹

U.S. Seal PS-3865R heavy duty 5/8 inch Viton carbon pump shaft seal

U.S. Seal Heavy Duty Salt and Ozone Service Shaft Seal, Viton Carbon, PS-3865R$15⁹⁹

Pentair 356173Z seal plate o-ring for the 3HP IntelliFlo3 pool pump

Pentair Seal Plate O-Ring for 3HP IntelliFlo3 Pool Pump, 356173Z$13⁹⁹

Waterway 400-4060 1-1/2 inch PVC pump half union assembly

Waterway Pump Union Assembly 1-1/2", 400-4060$8⁹⁹

Waterway 400-5570 pump union assembly, 2" nut by 2" slip

Waterway Pump Union Assembly, 2" Nut x 2" Slip, 400-5570$11⁹⁹

SuperPro 1000V-9 Viton heavy duty pool pump shaft seal for a 5/8 inch shaft

SuperPro Viton Heavy Duty Shaft Seal, 5/8" Shaft, 1000V-9$15⁹⁹

Waterway 400-5990 pump union assembly, 2.5 in. by 2 in., for Executive pumps

Waterway 2.5" x 2" Pump Union Assembly, 400-5990$14⁹⁴

Pentair 357100Z black seal plate gasket for IntelliFlo and WhisperFlo pumps

Pentair Black Seal Plate Gasket, 357100Z$10⁹⁹

Magic Plastics 0602-20 two inch pump union assembly

Magic Plastics 2" Pump Union Assembly, 0602-20$13⁹⁹

U.S. Seal RBL-6203-LL double sealed 6203 pool pump motor bearing

U.S. Seal 6203 Motor Bearing, RBL-6203-LL$12⁹⁹

Waterway 400-5670 pump union assembly with o-ring, 2 in. nut by 2 in. slip

Waterway Pump Union Assembly with O-Ring, 2" Nut x 2" Slip, 400-5670$11⁹⁹

Pentair 356148Z seal plate o-ring for the IntelliFlo3 VSF 1.5 HP pump

Pentair Seal Plate O-Ring for IntelliFlo3 VSF 1.5 HP Pump, 356148Z$13⁹⁹

U.S. Seal BC-36M-250S 36 to 43 MFD 250V start capacitor

U.S. Seal Start Capacitor, 36 to 43 MFD 250V, BC-36M-250S$8⁹⁹

US Seal CAPACITOR 189/227 MFD 125V | BC-189$14⁹⁹

U.S. Seal BC-270 270/324 MFD 125V motor start capacitor

U.S. Seal 270/324 MFD 125V Pool Pump Motor Start Capacitor, BC-270$12⁹⁹

Product details

The U.S. Seal PS-851 is a pump shaft seal assembly, also carried under the number PS851B. It is supplied as a complete assembly, the rotating half and the stationary ceramic seat together as a matched set.

What the shaft seal does

The shaft seal is the only thing keeping pool water out of the motor. Two lapped faces, one turning with the shaft and one fixed in the seal plate, run against each other under spring pressure. They wear as a pair, which is why a seal is always replaced as an assembly and why an old seat should never be reused with a new rotating half.

When to replace it

Water dripping from the joint between the wet end and the motor while the pump is running is the classic symptom. Left alone it runs straight into the motor bearings and turns a cheap part into a motor replacement, so a leak here is worth acting on quickly.

Make the new one last

Seals are destroyed by running dry. If the old seal failed early, look for a suction side air leak, a low water level or a blocked pump basket before you fit the new one, or the replacement will go the same way.

Specifications
Brand	U.S. Seal
Manufacturer part number	PS-851
Also listed as	PS851B
Type	Shaft seal assembly
Part type	Pool pump part
Supplied as	Complete seal assembly
Shipping weight	0.1 lb
Ships	Parcel

Request a quote

Need a volume price, a freight quote, or pricing in writing before you order? We reply the same business day.

Request a quote

Customer reviews

More from US Seal

U.S. Seal PS200 mechanical shaft seal assembly for pool pumps

U.S. Seal PS200 Mechanical Seal Assembly$12⁹⁹

U.S. Seal PS1000 mechanical shaft seal assembly for pool pumps

U.S. Seal PS1000 Shaft Seal Assembly$6⁹⁹

U.S. Seal PS201 pump shaft seal assembly with ceramic seat

U.S. Seal Pump Shaft Seal Assembly PS201$6⁹⁹

U.S. Seal PS-3867 heavy duty mechanical shaft seal assembly

U.S. Seal Heavy Duty Mechanical Seal Assembly (PS200), PS-3867$15⁹⁹

U.S. Seal PS-3868 heavy duty mechanical pump seal set

U.S. Seal Heavy Duty Seal Assembly, PS-3868$19⁹⁹

U.S. Seal PS-4231 generic mechanical shaft seal with a 13/16 inch ceramic inside diameter

U.S. Seal Mechanical Seal, 13/16" ID (Generic), PS-4231$25⁹⁹

U.S. Seal PS-3890 generic shaft seal assembly for Hayward Northstar pumps

U.S. Seal Shaft Seal Assembly (Generic), PS-3890$22⁹⁹

U.S. Seal Heavy Duty Salt and Ozone Service Shaft Seal, Viton Carbon, PS-3865R$15⁹⁹

Generic 5/8 inch inside diameter carbon and ceramic mechanical shaft seal for Jandy pumps

U.S. Seal Mechanical Seal, 5/8" ID (Generic), PS-4231-OS$19⁹⁹

U.S. Seal RD-50-370 run capacitor, 50 MFD 370 volts

U.S. Seal Run Capacitor 50 MFD 370V, RD-50-370$42⁹⁹

U.S. Seal 30 MFD 370 VAC run capacitor for pool pump motors

U.S. Seal Run Capacitor, 30 MFD, 370vac, 5VR0303$30⁹⁹

U.S. Seal PS-601 shaft seal assembly for a 3/4 inch pump shaft

U.S. Seal Shaft Seal Assembly, 3/4" Shaft, PS-601$19⁹⁹

U.S. Seal RD-25-370 round run capacitor, 25 MFD 370V

U.S. Seal Run Capacitor 25 MFD 370V Round, RD-25-370$27⁹⁹

U.S. Seal PS-3986 extra heavy duty shaft seal assembly for 3/4 inch shafts

U.S. Seal Shaft Seal Assembly, 3/4" Shaft, Extra Heavy Duty, Saltwater/Ozone Pools, PS-3986$27⁹⁹

U.S. Seal 6203 Motor Bearing, RBL-6203-LL$12⁹⁹

U.S. Seal PS100 Replacement Pump Seal Assembly$6⁹⁹

U.S. Seal Shaft Seal Assembly PS2131$15⁹⁹

US Seal CAPACITOR 35MFD 370V ROUND | RD-35-370$35⁹⁹

US Seal ASSEMBLY 3/4" CUP MTD | PS-201V-CMS$28⁹⁹

US Seal CAPACITOR 189/227 MFD 125V | BC-189$14⁹⁹

Questions and answers

What people ask about this product, answered by our pool techs.

Is PS-851 the same as PS851B?

This part is listed under both numbers. Match the number stamped on the seal you are replacing, or measure the shaft, if you need to be certain.

Does it include both halves of the seal?

Yes. It is supplied as a seal assembly, the rotating half and the stationary seat together.

Can I reuse the old ceramic seat?

No. The two faces wear as a pair. Fitting a new rotating half against an old seat will leak.

Why did my seal fail so quickly?

Almost always because the pump ran dry. A suction side air leak, a low water level or a blocked basket will destroy a new seal in minutes, so find the cause before rebuilding.

Ask your own question