Pentair 72173 stainless steel flat washer, 5/16 inch ID by 3/4 inch ODPentair Washer 5/16" ID x 3/4" OD, 72173 In stock$599
Pentair 72173 stainless steel flat washer, 5/16 inch ID by 3/4 inch OD
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Pentair Washer 5/16" ID x 3/4" OD, 72173

Ask a questionMPN 72173
$599
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Quick overview

  • Sized 5/16 by 3/4 Five sixteenths of an inch inside diameter, three quarters outside diameter.
  • Stainless steel Stays serviceable in the splash and chlorinated air of an equipment pad.
  • Flat washer Spreads the clamping load of the nut across the part instead of letting it dig in.
  • Four called for The source parts listing shows this washer as four required, so check your diagram before ordering one.
  • Wide fitment Listed for Pentair Challenger pumps, PF stainless side mount sand filters, Mitra and Mytilus cartridge filters and Purex CFM, CFW, 2000 and 4000 Series filters.
  • Factory part number Pentair 72173, the number to match when you are working from a parts diagram.
Full description and specifications ↓

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Product details

Pentair 72173 is a stainless steel flat washer measuring 5/16 inch inside diameter by 3/4 inch outside diameter. It is generic looking hardware that appears on a surprising number of parts diagrams, from Challenger pumps through PacFab Nautilus DE filters to the Purex CFM, CFW, 2000 Series and 4000 Series filter families.

What it does

A flat washer spreads the clamping force of a nut or bolt head over a wider area. On filter clamps and pump hardware that matters, because without it the fastener bites straight into the casting or the band and slowly deforms it. It also gives the fastener a clean, flat face to turn against so torque readings mean something.

Ordering

The source parts listing shows this washer as four required. That number belongs to a particular assembly, so count the washers you removed and work from your own diagram rather than assuming. Renew all of them together while the assembly is apart, since a corroded or dished washer will not clamp evenly against fresh ones.

Specifications
Brand Pentair
Manufacturer part number 72173
UPC 788379693541
Type Flat washer
Material Stainless steel
Inside diameter 5/16"
Outside diameter 3/4"
Quantity required 4 (per the source parts listing)
Fits Pentair Challenger pumps; Pentair PF stainless steel side mount sand filters; Pentair Mitra stainless cartridge filters; Pentair Mytilus B fiberglass cartridge filters; Pentair PacFab Nautilus and Nautilus Plus DE filters; Purex CFM 120, 180, 315 and CFW 120, 180, 315, 405 cartridge filters; Purex 2000 Series stainless DE filters; Purex 4000 Series molded DE filters
Shipping weight 0.05 lb
Ships Parcel

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Questions and answers

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

What size is this washer?
5/16 inch inside diameter by 3/4 inch outside diameter, in stainless steel.
How many do I need?
The source parts listing calls for four. Your own diagram is the final word, so count what came off the machine.
Is it stainless?
Yes. The parts listing describes it as a stainless steel flat washer, which is what you want on a wet equipment pad.
Will it fit my Challenger pump?
Pentair 72173 is listed in the Challenger pump parts diagram, along with a long list of Pentair and Purex filters. Match the part number on your diagram to be sure.
Ask your own question