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Leaking Febco 765 Vacuum Breaker: Complete Rebuild Procedure

Photo shows brass Febco 765 vacuum breaker with JB Weld on PVC connections. Leaking from bottom. Need removal/repair procedure.

Identify the Device

This is a Febco 765 atmospheric vacuum breaker (anti-siphon valve). Common on pool fill lines and irrigation.

Complete Replacement Procedure (Recommended Over Repair)

Shut off house water main
Cut PVC discharge pipe ~6" below elbow (by black wrap)
Unthread entire assembly (tee + hose bib + vacuum breaker) from wall pipe
Unscrew tee from vacuum breaker bottom
Replace galvanized tee with BRASS tee + brass nipple
Remove discharge male adapter + elbow (chisel off JB Weld if needed)
If plastic insert breaks in discharge valve, heat with torch to soften and remove
Reassemble: brass tee/nipple → vacuum breaker → hose bib on tee side
Reinstall on wall pipe, check for leaks with bottom valve closed
Reconnect discharge: new male adapter → PVC pipe → coupling → existing pipe → new elbow

Why Not Just Rebuild Kit?

Leak is at BOTTOM (pipe connection), not top. Rebuild kit fixes top seal only. The galvanized tee is corroded - must replace with brass. JB Weld indicates previous failed repair.

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