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Seacock 3/4" Flush, 90 Degree Hose Barb

Part #: Z3747
This 3/4" seacock valve became standard equipment on many Catalinas towards the end of 1993. This valve is configured with a flush through hull fitting and with a 3/4" 90 degree barb on top. Used as shower sump drain, sink drain, and ice box outlets as well as for marine head inlets. These valves are pressure tested when they are assembled, and should not be disassembled unless it is an emergency. To replace you will need to order the complete assembly, although you can often reuse the thru hull fitting.

Molded Marelon offers superior strength and corrosion resistance. Marelon is lightweight, corrosion and electrolysis free, ideal for thru-hull valves. Marelon is a modern material formulation of polymer composite compounds that uses resins and additives to produce an extremely strong marine-grade product that will not deteriorate like traditional bronze marine plumbing parts. Ideal for above and below the waterline applications.
Know usage: (there may have been others):
• Catalina 310: (3) total, (1) head intake, (1) head sink drain, and (1) engine raw water intake
• Catalina 315: (2) total, (1) head intake, (1) sink and shower drain
• Catalina 34: (2) total, (1) head intake, (1) ice box drain & shower sump outlet
• Catalina 350: (4) total, (1) head intake, (1) shower sump (note changed to a straight valve 3/26/03), (1) ice box drain, and (1) engine raw water intake
• Catalina 355: Head intake
• Catalina 36: Head intake
• Catalina 375: (3) total, (1) head intake, (1) ice box drain, (1) engine raw water intake (note drawing in manual calls out a straight valve)
• Catalina 380: (4) total, (1) fwd sink drain, (1) icebox drain, (1) head intake, and (1) shower drain
• Catalina 385: Head intake
• Catalina 387: (2) total, (1) head intake and (1) shower drain
• Catalina 390: (4) total, (1) fwd sink drain, (1) ice box drain, (1) aft sink drain, and (1) shower drain.
• Catalina 400: (4) total, (1) fwd head intake, (1) aft head intake, (1) fwd sump drain, and (1) aft sump drain
• Catalina 440: TBA (2 listed per valve kit)
• Catalina 445: (3) total, (2) head inlet, (1) sink drain
• Catalina 470: (4) total, (1) fwd sink drain, (1) aft sink drain, (1) aft head intake, and (1) gray water discharge
• Valve configuration: 90 degree elbow hose barb
• Height from base to top of handle when valve is open (maximum height not including wood mounting ring): 4-1/2"
• King nut diameter: 3-1/8"
• Thru-hull minor diameter: 1-9/32"
• Thru-hull major diameter: 1-23/32"
• Thru-hull outside diameter: 1-3/32"
• Thru-hull inside diameter: 5/8"
• Thru-hull length overall: 3"
• Thread type: Buttress

The thru-hull uses a buttress style thread with 45 degree angled threads for exceptional strength and are not compatible with any other valves. A buttress thread design with the same amount of clearance as for a conventional pipe thread will give the impression of greater looseness. However, when the joint is taken up tight, there is a greater area of surface between threads with the buttress thread form creating greater load capacity. Like any threaded pipe assembly thread compound or Teflon tape applied to the threads to seal is required.
1) If your through hull has a mushroom through hull and it needs to be replaced as well, order Thru Hull Mushroom for 1/2" or 3/4" Seacock listed below in "May we also suggest".
Each valve is factory assembled and pressure tested. We cannot be responsible for valves disassembled and modified or reassembled improperly.
3) The buttress thread on these seacocks is not compatible with and will not work with a traditional through hull thread type. The seacock and through hull fitting must be replaced in sets at the same time.
C-315, C-355, C-375, C-385, C-445

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