Gasket Makers & RTV Silicone

Specification

Everything published for this product. Anything not listed here is not published — ask and we will confirm it for the unit you are buying.

What it is

Room-temperature-vulcanising silicones and sealing compounds that form a gasket in place between two mating faces, curing from a paste into rubber, plus the non-hardening compounds used alongside a conventional gasket.

Who buys it

Plant and facilities maintenance, generator and pump servicing, engine rebuilders and fleet workshops holding their own consumables.

Made of

Silicone chemistry, with the cure system and the filler varying by grade. The datasheet is the authority, not the shelf label.

How it works

An RTV silicone cures on contact with moisture in the air, so it skins over in minutes and takes hours to cure through. Form-A-Gasket and Spray-A-Gasket are different animals — they stay tacky and non-hardening and are used WITH a gasket, not instead of one.

Choosing the colour

Ultra Black is flexible with maximum oil resistance and is sensor safe — the default where the joint sees engine oil. Ultra Blue is the multi-purpose one, sensor safe, for general gasketing where neither extreme heat nor constant oil is the problem. Versachem Mega Gray is sensor safe and rated −65 °F to 450 °F continuous, 650 °F intermittent. Versachem Mega Copper is the high-temperature one, resisting up to 700 °F, for exhaust and turbo work; its maker describes it as low-volatile and suitable for vehicles with oxygen sensors, which is not the same phrase as sensor safe, so ask if your engine is sensitive. Permatex high-temperature red runs −65 °F to 650 °F. The general-purpose clear RTV is for non-structural sealing where appearance matters and heat does not — see the warning below before putting it near a sensor.

Where it is the wrong choice

Check "sensor safe" before anything else on a modern engine. An ordinary acetoxy silicone gives off acetic acid as it cures, which attacks oxygen sensors — cure a leak with the wrong tube and you may buy a sensor. Ultra Black, Ultra Blue, Mega Gray and the high-temperature red are sold as sensor safe. The 66C general-purpose clear adhesive sealant on this shelf is NOT, and it is the one the warning is about — keep it away from sensors and away from anything above 400 °F. And check the temperature rating before using any of them near an exhaust or a turbo.

Brands

Permatex and Versachem.

Genuine stock

Genuine Permatex and Versachem stock, held at our own warehouse rather than drop-shipped. What you order is what is on the shelf, and batch and shelf life are confirmed on request.

Storage

Cool and out of the sun. A UAE store room in August will take months off the shelf life of anything on this list.

Delivery

All 7 Emirates from our own yard. Sharjah and the northern emirates are usually same day on stocked lines; the rest of the country is one to three working days.

Trade and volume

Volume pricing above trade quantities for workshops, fleets, facilities contractors and car wash operators. Send the whole list rather than one line and we will price the package instead of the item.