J -B Weld Hi-Temp Red Silicone Gasket Maker and Sealant is an RTV (Room Temperature Vulcanized) silicone gasket material, designed for use in mechanical assemblies where the existence of higher, continuous temperatures up to 285°C or 340°C intermittent might exist.
We tested it at TAFE NSW – Wollongbar and used the sealant on the sump gasket, during an engine overhaul task which we were currently working on. The sealant formed a nice even bead as would be expected from any small sealant tube. I was impressed by the thickness of the plastic in the nozzle, which meant that it was robust and would not easily bend and could be blocked to preserve sealant for future use with ease.
The sealant adhered to the housing very well and even stuck to areas which had small traces of oil, which is not in keeping with the recommended preparation, but was impressive none the less.
Many of the students at TAFE NSW – Wollongbar had already used the sealant within their own workplaces and offered glowing reports as to its long-term performance and reliability – the peace of mind knowing that a product will offer a reliable, effective solution as return jobs equals lost income.
We also applied the product to the exhaust manifolds. It held nicely in position while in a vertical location – the smaller tube makes it easy to apply in tight and hard-to-access areas. When the product is exposed to moisture in the air, the silicone forms a tough, waterproof seal on most surfaces. Large volumes of silicon will not cure internally, so stick to the recommendations of approximately 5mm thickness.
Product details state it will not shrink or crack, it resists weathering and is great for many automotive applications. The sealant sets in an hour and fully cures within 24 hours. It is sensor safe which is critical in our technically advanced industry.