Silicone sealant (RTV) is one of the most useful products in the shop, and one of the most misused. Used in the right place it prevents leaks. Used in the wrong place, it can cause them, or end up in the oil pickup.
When to Install the Gasket Dry
- Head gaskets. Install dry unless the gasket instructions say otherwise. Sealant can interfere with coatings and fire rings.
- Molded rubber gaskets for valve covers, oil pans and intake manifolds are designed to seal on their own on a clean surface.
- Coated or MLS gaskets. The coating is the sealant.
Where a Small Dab of RTV Belongs
- Joints and corners where two parts meet, such as where the timing cover meets the block at the oil pan rail, or at the ends of an intake valley seal.
- Follow the gasket instructions for exact locations. A small dab is enough.
When RTV Replaces a Gasket
Some engines are designed for formed-in-place sealant instead of a cut gasket. In that case, use an RTV that meets the application and apply a continuous, even bead.
Tips for Using RTV Correctly
- Surfaces must be clean, dry and oil-free. See Gasket Surface Preparation.
- Use a thin, even bead. Excess squeezes inside the engine and can block oil passages or the pickup screen.
- Assemble within the working time on the label, then let it cure before adding fluids.
- Choose a sensor-safe, oil-resistant product for engine work.
Evergreen High Temp RTV Silicone Gasket Maker
Evergreen High Temp RTV Silicone Gasket Maker (Grey, 1.13 oz / 32 g) is made for engine sealing jobs: corners and joints alongside Eversealed™ Technology gaskets, and formed-in-place applications where the engine is designed for RTV. The tube comes with an applicator nozzle for a clean, even bead. Find it in our product catalog.
