JYINCPED Transfer Tank Vented Diesel Fuel Cap — 2" Threaded Neck, Lockable Spring-Seal, Corrosion-Resistant

This heavy-duty transfer tank cap is designed as a direct-fit replacement for standard 2" NPT threaded tank bungs and fills the same role as fill-rite and Dee Zee caps on mobile diesel, farm, and commercial fuel tanks. Constructed with corrosion-resistant materials, it combines a cast-iron base with a removable vented cap, an internal gasket, and a spring-loaded seal to stop leaks while allowing controlled venting when needed.

How does this vented diesel cap protect my tank during refueling and transport?

The cap vents in both directions to relieve positive pressure and allow air in as fuel leaves the tank. That prevents excessive vapor pressure during filling and avoids dangerous vacuum that can collapse or deform a transfer tank when pumping out fuel.

• Vents outward as you loosen the cap to safely release built-up pressure.
• Admits air to prevent vacuum formation while dispensing fuel.
• Spring-loaded gasket maintains a tight seal during normal operation and transport.

Will this fit my existing transfer or auxiliary diesel tank?

Yes — the cap assembly is intended to replace transfer tank vented caps that use a standard 2" NPT threaded neck. The heavy-duty cast iron base matches common tank bung dimensions used on many mobile and stationary fuel tanks.

• Standard 2" NPT threaded neck for broad compatibility.
• Designed as a replacement for Dee Zee and Fill-Rite style caps.
• Works with transfer, auxiliary, mobile, and weather-guard tanks.

How secure and leak-resistant is the fuel cap?

Security is increased with a built-in lock tab that accepts 1/4"–5/16" shackle padlocks (padlock not included), helping deter theft and tampering. The interior gasket plus spring-loading compresses the seal tightly when closed, reducing leaks and limiting excess vapor escape while driving.

• Lockable tab secures the cap against siphoning and vandalism.
• Compression gasket and spring keep a reliable leak-resistant fit.
• Robust materials resist corrosion for long-term service.

How simple is it to install and operate this vented cap?

Installation and daily use are straightforward: align the cap with the notch, push down and twist clockwise to tighten. To remove, twist counter-clockwise to the vent position to release pressure, then lift; the action is intuitive even when wearing gloves.

• Push-down and clockwise twist to fully engage the seal.
• Counter-clockwise to notch for controlled venting before removal.
• Removable cap design allows easy cleaning and inspection.

Who this is for: This JYINCPED vented transfer tank cap is ideal for farmers, fleet managers, contractors, and anyone operating mobile fuel systems or auxiliary diesel tanks who needs a dependable, leak-resistant cap with venting and optional padlock security. It suits applications on ground-service, commercial, and distillate storage where standard 2" NPT bungs are used and where preventing pressure/vacuum damage, theft, or fuel loss is a priority.