In The Shop: Vinegar Smell Means Caution When Working On Electronics
May 15, 2011
Ever notice that some RTV silicone sealants sold in auto parts stores are labeled, "Safe For Oxygen Sensors"? That's because some RTV silicones (RTV stands for "Room Temperature Vulcanizing, by the way, which means they cure at normal room temperature without special curing agents or need for baking in an oven) create acetic acid vapors as they cure. Acetic acid vapors can corrode exposed metal on electronic circuitry.
There have, in the past, been problems when RTV silicones were used to seal engine components during repairs, and acetic acid fumes from the curing silicone damaged the oxygen sensor elsewhere on the engine. Hence the development of RTV silicones that don't create acetic acid during the curing process.
FYI, acetic acid smell like vinegar. If you're using silicone sealant during repairs to vehicles or farm equipment and smell vinegar, consider if those fumes could damage nearby electronics.