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Gray 300 mL cartridge of Loctite SI 5999 silicone gasket maker paste

Loctite

Loctite 231230 Silicone Gasket Maker 300 mL Gray

SKU CH-39AP-V83N1

Gray RTV silicone gasket maker cures at room temperature in seven days, resists oil and temperatures from -65 °F to 550 °F, and fills gaps up to 0.25 in

  • Withstands extreme heat up to 550 °F
  • Remains flexible in cold down to -65 °F
  • Fills gaps up to 0.25 in on metal surfaces
  • 10 min working time allows precise positioning
  • Resists oil and high temperatures for lasting seals

What this gasket maker does

Loctite 231230 is a room-temperature-vulcanising silicone paste supplied in a 300 mL cartridge. It forms flexible, oil-resistant gaskets on metal flanges and housings. The grey compound withstands continuous temperatures from -65 °F to 550 °F. Full cure is reached after seven days.

Suited for original-equipment repairs

Mechanics resealing engine, transmission or differential covers will find the 0.25 in gap-fill capacity and ten-minute working time practical. The product is not intended for structural bonding, large voids beyond the stated gap limit, or non-metallic substrates that require a different chemistry.

Deciding specification: temperature range

The -65 °F to 550 °F operating window determines whether the seal survives the application. Verify that the assembly never exceeds these limits before selecting this compound.

Highlights

  • Withstands extreme heat up to 550 °F
  • Remains flexible in cold down to -65 °F
  • Fills gaps up to 0.25 in on metal surfaces
  • 10 min working time allows precise positioning
  • Resists oil and high temperatures for lasting seals

Specifications

BrandLOCTITE

Questions about this item

How do I install the Loctite 231230 cartridge and what is the common mistake?

Load the 300 mL cartridge into a caulk gun, apply a continuous bead on one clean flange, then assemble within the 10 min working time; the frequent error is waiting longer than 10 min before mating the parts.

What maintenance or replacement will the cured gasket need later?

Once fully cured after 7 days the silicone gasket remains in place for the life of the joint; no scheduled maintenance or replacement is required unless the seal is damaged or the assembly is disassembled.

What limit appears first during sustained high-temperature use?

The maximum continuous operating temperature is 550 Degrees F; exceeding this limit will degrade the silicone before any other property becomes critical.

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