BLACK SILICONE SEALANT & ADHESIVE
BLACK SILICONE SEALANT & ADHESIVE
BLACK SILICONE SEALANT & ADHESIVE
SKU: 31319

BLACK SILICONE SEALANT & ADHESIVE

$9.99

Attributes

Mold and Mildew Resistant
Water Resistant

Use On

Automotive
Glass
Metal
Wood
Plastic

Product Details

J-B Weld Black Silicone Sealant and Adhesive is a general purpose RTV (Room Temperature Vulcanized) Silicone, designed for sealing and bonding uneven surfaces. Upon curing, which occurs when the product is exposed to the moisture in air, the silicone forms a tough, waterproof seal on most surfaces. It will not shrink or crack, resists weathering and is great for many automotive accessories and household applications.

Get the Safety Data Sheet

Product Attributes

Set Time
1 Hour
Dry Color
Black

Surfaces

Automotive
Glass
Metal
Wood
Plastic

How to Use

Prepare

For best results, clean and dry surface area

Apply

Apply even, continuous ¼ inch bead of Silicone to one surface area. Surround all bolt holes with Silicone.

Assemble

Reconnect parts while Silicone is wet.

Secure

Hand tighten until Silicone begins to squeeze out.

Dry

Allow drying for 1 hour and then tighten an additional ½ turn.

Finish

Scrape or cut away excess cured sealant. Silicone will fully cure in 24 hours.

Frequently Asked Questions

Is Black Silicone Sealant the same as Ultimate Black, and is it oil resistant?

They are different products. Black Silicone Sealant 31319 is a general-purpose sealant and adhesive and is not oil resistant. Ultimate Black Gasket Maker 32329 is the oil-resistant one, formulated for maximum petroleum resistance on oil pans, valve covers, and differential covers. Use 31319 for weatherproofing, trim, and household sealing where no oil or fuel is present.

What temperature can Black Silicone Sealant handle?

J-B Weld does not publish a temperature rating for this product on its page, and support has quoted figures between 450 F and 550 F, so treat it as a moderate-heat general sealant rather than a rated high-heat gasket maker. For anything near an exhaust, manifold, or engine hot spot, use Hi-Temp Red 31314, which is rated to 550 F continuous and 650 F intermittent.

Is Black Silicone safe on painted surfaces, and how do I remove it later?

It will not attack cured automotive paint in normal use, but it is an acid-cure silicone, so for bonding directly to a painted finish J-B Weld recommends a neutral grey RTV instead. To remove it, peel or pare the bulk away with a plastic razor blade, then soften the residue with a solvent such as acetone. Test any solvent on a hidden area first.

Does Black Silicone stay flexible, and can it be sanded smooth?

It stays flexible. It cures to a rubbery consistency that will not shrink or crack, which is what lets it seal uneven surfaces and absorb movement. Because it is rubbery, it cannot be sanded to a smooth finish; sandpaper tears and gums it. Tool the bead with a wet fingertip or a plastic spreader within the one-hour set time to get the shape you want.

Can I use Black Silicone to bond weatherstrip or rubber seals to metal?

No. RTV silicone does not hold well on rubber weatherstrip or trunk seals and tends to make a mess at the joint; use an adhesive sold specifically for weatherstrip. It does work for bonding and sealing rigid plastic trim to metal, such as a windshield header trim piece, where the seal is the main job and the part is not carrying load.

Reviews