4240c Mechanical Seal (PS-4240) — 5/8″ (Goulds 10K10)

4240c Mechanical Seal (PS-4240) — 5/8″ (Goulds 10K10)

The 4240c mechanical seal is a direct-fit 5/8″ shaft seal, the PS-4240 equivalent, cross-referenced to Goulds 10K10. It is built to OEM-equivalent standards or higher with a Type 166 footprint and a machined carbon face for longer service life.

Machined Carbon Face 
Our 4240c uses a precision-machined, resin-impregnated carbon face — not the molded plastic/phenolic carbon found in standard equivalents — for smoother sealing and longer life. For the standard molded carbon version, see our 680c seal.

At a Glance 

• Goulds Reference: 10K10 (also 10K121, 10K258)

• PS Reference: PS-4240 / 4240c

• Shaft size: 5/8″

• Cup Seat:1.187″ × 0.288″ / 0.296″ (verify thickness)

• Footprint: Type 166 (replaces Type 16 / G / A / 6 / AV / 2100 styles)

• Faces: Ceramic/Carbon: Machined carbon (not molded/phenolic) vs. ceramic, with Nitrile elastomers — for smoother sealing and longer life.

Why This Seal

Our Carbon/Ceramic build uses precision-machined, resin-impregnated carbon — not the plastic/phenolic used in PS-702 and similar equivalents — for smoother sealing and longer service life.

Applications

Built for Goulds pumps using the 5/8″ shaft and Type 166 seal arrangement. Matching from a worn seal? Confirm your shaft size and cup seat thickness first, or send a photo of the old seal and your pump nameplate to info@sealhouseusa.com, or call/text 561-414-1046. No purchase required.

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