Ullage requirement, or the airspace necessary in a fuel tank, is dependent both on tank shape and tank and boat size. Boatbuilders who leave too little ullage risk tank over-pressurization. Too much airspace, on the other hand, sacrifices precious range unnecessarily. Perko offers an easy and affordable solution, even for unusual or large tanks, with its new 0586XL series fill limit valves.

Locating a valve outside the standard 1/2″ to 1-1/2″ setting range presents a challenge. Until now, boatbuilders have had to pay the tank’s manufacturer for modification, an expensive and imperfect solution.

Designed to work specifically for larger boats with deep fuel tanks, Perko’s new 0586 series valves come in extra large versions in addition to all the standard sizes. Besides offering the popular 3/8″, 1/2″, 3/4″,

1-1/8″ and 1-1/2″ heights, Perko now provides valves with shutoff heights ranging from 2″ up to over 6″, in 1/2″ increments.

Boatbuilders can order the new fill limit valves in quantities as low as five pieces. Custom sizes between 1-1/2″ and 10″ are also available when purchased in quantities of 25 or more.

Prices for the new 0586XL fill limit valve series start at $32. Like all Perko tank-mounted valves, the 0586 and 0586XL series come in 1″ NPTF threaded, SAE five-bolt pattern flanged, or swivel versions.

Image courtesy Perko