Loctite
Loctite 743519 RTV Silicone Sealant 190 mL Black
Black RTV silicone sealant withstands -65 °F to 450 °F, cures in one day and seals automotive fluids on metal, glass and rubber
- TypeCaulks
- Withstands extreme heat up to 450 °F for engine gaskets
- Remains flexible in cold down to -65 °F for year-round reliability
- Ready to handle fluids in 30 minutes working time
- Bonds metal, glass, rubber and fibreglass for versatile repairs
- 190 mL pressurised can delivers controlled bead with trigger
Black RTV silicone for automotive sealing
Loctite 743519 is a black RTV silicone sealant supplied in a 190 mL pressurised can with trigger. It forms a flexible paste gasket that bonds to metal, glass, fibreglass and rubber. The product cures at room temperature and is designed for automotive fluid systems.
30-minute work window and 1-day full cure
After application you have about 30 minutes to assemble parts before the sealant skins over. Full cure completes in one day at room temperature. The cured seal remains effective from -65 °F up to 450 °F, covering typical engine, gearbox and cooling-system temperatures.
Trigger can enables controlled bead placement
The pressurised can with trigger lets you lay a consistent bead directly onto flanges or into grooves without a separate caulking gun. This reduces mess and waste on irregular surfaces such as water-pump housings, thermostat housings or differential covers.
Highlights
- Withstands extreme heat up to 450 °F for engine gaskets
- Remains flexible in cold down to -65 °F for year-round reliability
- Ready to handle fluids in 30 minutes working time
- Bonds metal, glass, rubber and fibreglass for versatile repairs
- 190 mL pressurised can delivers controlled bead with trigger
Specifications
| Type | Caulks |
|---|---|
| Brand | LOCTITE |
Questions about this item
Will the SI 593 black paste adhere to the metal and rubber parts I am keeping from my current build?
The product is rated for metal, rubber, glass and fiberglass substrates, so it will bond to those materials you are reusing.
How can I confirm the SI 593 paste has cured properly after the full-cure period?
After one day at room temperature the paste reaches full cure; a uniform black colour and firm, non-tacky surface indicate it has set correctly.
Does the 190 mL pressurised can include a nozzle, or must I buy a separate applicator?
The container is a pressurised can with a built-in trigger dispenser, so no extra applicator is required.
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