1-5/8 in. RED FILL CAP WITH ALUMINUM BOLT-ON BUNG1-5/8 in. RED FILL CAP WITH ALUMINUM BOLT-ON BUNGCap and Bolt-On Bung InstalledProudly Made In The USA
Quantity Your Price
1 $51.99

C73-736-B

1-5/8 in. RED FILL CAP WITH ALUMINUM BOLT-ON BUNG

1-1/4-12 Straight Thread
4 on 2 in. Dia. Bolt Circle
9/16 in. Bung Height

Includes mounting hardware and Buna O-rings.

Made in the USA

(Cap Replacement O-Ring is C73-749 & Bung Replacement O-Ring is C73-748)


Bolt-On Bung and Cap Assembly


The Pro-Werks Bolt-on fill assemblies require no welding; this produces a very clean finished installation every time. The base of the bung is machined to accept the provided Buna O-ring for a positive seal, mounting hardware is included.


Leak proof.
There are many very useful applications; ideal for composites when welding isn't an option and thin gauge materials that are too difficult to weld, or any installation that already has a sensitive protective finish applied. These are a favorite of engine builders for valve covers.

Fitted with the popular non vented Easy Turn Fill Cap, featuring positive grip finger notches that are easy to get a hold of. The 6061-T6 billet aluminum cap is CNC machined into a lightweight, attractive design with quick-starting coarse threads and positive sealing "radially squeezed" Buna O-Ring – which also holds the cap secure.


Great caps. Great colors.



To compliment the color coordination of your project, the caps are finished off in Pro-Werks Brilliance anodized colors in your choice of  black, red, blue, silver, or beautifully Micro-polished aluminum – the finishes are impeccable.


The right size matters.



Easy Turn Fill Caps come in many sizes and are packaged as complete assemblies with your choice of one of the many versatile mounting options, or each component is also available separately.



Be sure to check out the entire line up - Billet aluminum Easy Turn Fill Caps are a Pro-Werks specialty.  Watch the Video below to learn more !


Proudly Made in the USA

Customer Comments:


"I use your bolt on caps and bungs on my carbon fiber Cummins common rail valve covers. Love the quality. Thank you."
             Randy Davis, Owner of OldSkoolFab, Inc.







Finish Your Tank

We also offer a full line of weld-in plumbing bungs to complete your tank project.

Click the images below to view all the options.


   



Q:

How much do I need to tighten a fill cap?

A:

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.

 



Q:

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

A:

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

 



Q:

What is Buna and is it compatible with my fluid?

A:

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.

 

1-5/8 in. Red Fill Cap: C73-741
Inside Grip Diameter: 1.625 in.
Outside Grip Diameter: 1.970 in.
Height: 0.5 in.
Height: 0.312 in.
Thread: 1-1/4-12
Aluminum Bolt-On Bung: C73-746
Diameter: 1.5 in.
Thickness: 0.188 in.
Thread: 1-1/4-12
Holes: 0.172 Dia.
Bolt Circle: 4on 2.0 in.
Outside Diameter: 2.438 in.
Thickness: 0.375 in.
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