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Easy Turn Fill Cap with O-Ring

SKU C73-744
Cap Size
Fill Cap Color
Regular price $40.99

Spend $175 to get free shipping
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Easy Turn Fill Cap Replacement O-Ring, Buna Material

Easy Turn Fill Cap Replacement O-Ring, Buna Material


1-5/8 Inch Fill Cap
1-1/4-12 Straight Thread
No Lanyard Boss
Includes O-Ring
(Cap Replacement O-Ring is C73-749)

2 Inch Fill Cap
1-1/2-12 Straight Thread
Includes O-Ring
No Lanyard Boss
(Cap Replacement O-Ring is C73-769)

2-3/4 Inch Fill Cap
2-1/4-10 Straight Thread
With Lanyard Boss, Accepts Lanyard Chain Kit
Includes O-Ring
(Cap Replacement O-Ring is C73-788-A)

4-1/4 Inch Fill Cap
3-3/4-8 Straight Thread
With Lanyard Boss, Accepts Lanyard Chain Kit
Includes O-Ring
(Cap Replacement O-Ring is C74-788-A)

 


Choose your size. Choose your color.

Fill Cap with O-Ring


These lightweight, signature Pro-werk non-vented Fill Caps feature deep finger notches for a positive and comfortable grip, this design is another Pro-werks innovation, appreciated by everyone who uses them. The 6061-T6 American melt billet aluminum is CNC machined for accuracy, and is available in your choice of either brilliance anodized black, red, blue, or silver, as well as micro-polished aluminum - all of these finishes are impeccable.


Great caps. Great colors.

 



This design uses a radial squeeze action on a Buna O-ring for a secure seal. Precision machined quick-start coarse threads make using these caps a breeze.

The large selection of Pro-werks’ mounting bungs are crafted from steel, aluminum or stainless steel and available in both weld and bolt-on styles.

 

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.


Popular uses for Easy Turn Fill Caps include:

  • Custom-fabricated tanks
  • Fuel cells
  • Rear End housings
  • Valve covers
  • Overflow tanks
  • Ice boxes for intercoolers
  • Ballast tanks
  • Inspection viewing ports

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 here 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.



"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


 

 

 






FAQs
Q: How much do I need to tighten a fill cap?
A: It is not necessary to bottom the fill cap into the bung−just adequately seat the O-ring. The radial squeeze action on the O-ring creates a positive seal and helps prevent the cap from coming loose.

Q: What should I use to lubricate the Buna O-ring?
A: Applied periodically, a light coating of Dielectric grease has proven to work well as an O-ring lubricant.

Q: Is Buna rubber compatible with my fluid?
A: Buna is a synthetic rubber compound suitable for use with most fluids. Buna components may need to be replaced by a material compatible with the specific chemistry of some fluids.

Q: How do I properly weld my bung?
A: Apply several small, equally spaced tacks and preheat before welding. Keep the weld small to minimize potential distortion or shrinkage.

Q: If my threads are tight after welding, how do I fix it?
A: The solution is simple. Apply a small amount of fine grit lapping compound to the threads then turn the cap back and forth in the bung until the desired fit is achieved. Be patient−do not force the process. Thoroughly clean both sets of threads before use.

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