Quantity Your Price
1 $66.95



2-1/4-10 Straight Thread
6 on 4.438 in. Dia. Bolt Circle
3/4 in. Bung Height
Includes mounting hardware and Buna gasket

Pro-Werks provides another new improvement for racers and rodders alike. Fuel Cell users can now easily upgrade their Cells from troublesome Flip style filler or Bail cap, to the popular non-vented, Easy Turn Fill Cap Assembly from Pro-Werks. This assembly is a simple bolt on installation. The Billet Aluminum Fuel Cell & Filler Cap is a Pro-werks specialty.

The positive grip finger notches of the Easy Turn Caps are easy to get a hold of. This design is another Pro-werks innovation, and is appreciated by everyone who uses them.  Featuring quick acting coarse threads with a starter nose to accurately lead the cap into position. Each is standard with a special positive sealing " radial squeeze " Buna O-ring, which also holds the cap secure. The Pro-werks Fuel Cell cap also includes a built in lanyard boss feature, enabling the use of the optional lanyard chain to keep the cap close by if you so desire.

  Easy Turn caps are available in a large selection of Pro-Werks Brilliance Anodize Finish colors or beautiful Micro-polished aluminum. The bung of  this assembly is also available in your choice of two anodized colors, Silver or Brilliance Black. The extensive selection of color combinations gives you the opportunity to match your individual style. Includes all the necessary stainless mounting hardware and the Buna flange gasket.

Both the cap and bung are precision CNC machined to exacting tolerances, of light weight billet aluminum, right here in the USA ( Mears, Michigan ).

You can always count on Pro-werks to do it right.

"I upgraded my fuel cell to an Easy Turn fill cap assembly. It wasn't long until all my friends did the same. Great product!"
             As shared with us at the
PRI Show


How much do I need to tighten a fill cap?


It is not necessary to bottom the fill cap into the receiving bung. Adequately seating the O-ring to make a seal is all that is required. The radial squeeze action on the O-ring creates a strong seal and helps to keep the cap from coming loose.



What should I use to lubricate a Buna O-ring?


A light coating of Dielectric grease works very well as O-ring lubricant.



What is Buna and is it compatible with my fluid?


Buna is a universal composition synthetic rubber, a standard of plumbing related products because it is compatible with many fluids. Due to the complex chemistry of modern day performance oils and fuels, you may find it necessary to replace Buna components with a material that is compatible with the unique chemistry of your specific fluids.


2-3/4 in. Blue Fill Cap: C73-782
Outside Grip Diameter: 3.200 in.
Height: 0.312 in.
Thread: 2-1/4-10
Height: 0.625 in.
Inside Grip Diameter: 2.750 in.
Aluminum Fuel Cell Bung: C73-712
    Diameter:     2.625 in.  
    Thickness:     0.25 in.  
    Thread:     2-1/4-10
    Thickness :     0.50 in.  
    Holes:     0.265 in.
Dia. Hole
    Bolt Circle:     6 on 4.4 in. Bolt Circle  
    Outside Diameter:     5.25 in