yamaha knows his stuff. I will add a few comments for additional info.
First, RTV stands for Room Temperature Vulcanizing. It cures when exposed to air, and it cures fastest at room temperature (i.e., 72 deg F). The colder the environment, the longer it will take to cure.
Second, RTV compounds come in many different colors. High temperature resistant compounds are most likely red due to the addition of iron oxide. Other colors (black, white, blue, or translucent) do not indicate any brand or physical charactertics.
Third, sealing surfaces of the mating parts must be cleaned with a chlorinated solvent, such as carbuerator spray cleaner, brake cleaner, or alcohol. (Do not use petroleum-based cleaners such as mineral spirits, because they leave a film onto which the RTV will not stick!) Cleanliness of mating parts is very important. All materials (nylon, sheet metal, cast iron, and aluminum) are equally susceptible to leaks if the surface has grease and oil contaminants. Surfaces must be kept as clean as possible when assembling with RTV.
Fourth, during application, RTV often requires (depending on the brand) an initial cure time of 15 minutes after the bolts are torqued to allow for the RTV material to skin over. (Never let the material skin over before joining the mating parts.) In an automotive engine application, follow-up the installation with an engine warm-up of 15 minutes. During this 15-minute run, the parts should be inspected for leaks. This should be followed by a shut-down of approximately 45 minutes, called a soak, before the engine is operated under normal conditions. The initial skin-over allows for a set of the RTV to prevent liquid lubrication systems from leaking, and the warm-up provides heat in order to accelerate the curing process. The 45-minute soak period allows a thicker skin build-up in areas of excess RTV bead thickness and further reduces the chance of any of the excess falling off. The longer the soak, the better, and overnight curing is recommended when possible.
