Rustex ~ Rust Inhibitor



Castle® Rustex™ is a stabilizer and inhibitor that neutralizes radiator coolant, preventing rust, corrosion, and scale. Rustex™ leaves no oily film usually present in most other rust inhibitors. Rustex™ also works as a lubricant to the water pump. It can be used in all types of radiators, including plastic. Rustex™ is a silicate-based formula and should not be used in conjunction with silicate free antifreeze.


  • Auto
  • Truck
  • Bus
  • Farm Equipment
  • Heavy Equipment
  • Fork Lifts


1. 12 ounce bottles should be added to the cooling system every six months or 10,000 miles in automotive applications.
2. A 12 ounce bottle will treat up to a 20 quart system.


  • 8 oz (#C0834) 24/case
  • 12 oz (#C1204) 24/case
  • 5 gal (#C1204-5) pail
  • 15 gal (#C1204-15) drum
  • 55 gal (#C1204-55) drum


  • Color – blue
  • Flash Point – 407°
  • Cleaning – excellent
  • Effect on Paint – none
  • Odor – none
  • pH – 14
  • Density – 1.1
  • Freeze Stable – yes
  • Degreasing – yes


When handling this product wear gloves and eye protection. This is a high pH product.

Product #:

C0834, C1204, C1204-5, C1204-55

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U.S. Customers
Castle AutoChem Products Ltd services Canadian customers only.

U.S. customers, please visit the Castle U.S. Website,
or call 1-800-876-0222.