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Black Loctite SI 5900 RTV gasket maker in a 300 mL cartridge

Loctite

Loctite 212184 SI 5900 RTV Gasket Maker 300 mL Black

SKU CH-QCKF-FTF5Q

Black RTV gasket maker forms an oil-resistant seal on metal and plastic in 15 minutes and withstands -65 °F to 400 °F

  • Forms instant oil-resistant seals on metal and plastic
  • Cures fully in one day at room temperature
  • Withstands temperatures from minus 65 °F to 400 °F
  • Fills gaps up to 0.25 inch with 15-minute working time
  • 300 mL cartridge delivers ample material for large jobs

Gasket Maker for Metal and Plastic

Loctite SI 5900 RTV gasket maker forms a flexible, oil-resistant seal between metal and plastic flanges. The black paste cures at room temperature to a durable rubber that withstands temperatures from minus 65 to 400 degrees Fahrenheit. It is supplied in a 300 mL cartridge for use with a standard caulking gun.

Fits Standard Caulking Guns and Flanged Joints

The cartridge fits any standard 10.14 fl oz caulking gun so no special dispensing tool is required. A 15-minute working time allows precise placement and assembly of parts before the seal begins to skin over. Full cure completes in one day, freeing the joint for service without prolonged downtime.

Seals Gaps Up to 0.25 Inch in High-Temperature Oil

The paste fills gaps up to 0.25 inch and maintains its seal through thermal cycling in engines, transmissions and gearboxes. It is not suited for gaps larger than 0.25 inch or for fluids other than oil. Buyers needing larger gap fill or compatibility with coolant or fuel should select a different formulation.

Highlights

  • Forms instant oil-resistant seals on metal and plastic
  • Cures fully in one day at room temperature
  • Withstands temperatures from minus 65 °F to 400 °F
  • Fills gaps up to 0.25 inch with 15-minute working time
  • 300 mL cartridge delivers ample material for large jobs

Specifications

BrandLOCTITE

Questions about this item

How thick a gap can the SI 5900 paste fill before it stops sealing?

The cartridge is rated to fill gaps up to .25 in, so joints wider than that need shimming or a different method.

Will the cured gasket hold up when the engine runs at 400 Degrees F all day?

Yes, the material is rated for a maximum operating temperature of 400 Degrees F and stays flexible down to -65 Degrees F.

Do I need a standard caulking gun to apply the 300 mL cartridge?

The product comes in a 10.14 fl oz cartridge that fits any standard caulking gun for hand application.

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