GM Service Manual Online
For 1990-2009 cars only

The following 2 types of sealer are commonly used in engines:

    • The RTV sealer
    • The anaerobic gasket eliminator sealer

Follow the service procedure instructions. Use the correct sealer in the proper place in order to prevent oil leaks. Do not interchange the 2 types of sealers. Use the sealer recommended in the service procedure.

Applying RTV Sealer

    • Do not use the room temperature vulcanizing (RTV) sealant in areas where extreme temperatures are expected. These areas include the following locations:
       - The exhaust manifold
       - The head gasket
       - The other surfaces where gasket eliminator is specified
    • Use a rubber mallet in order to separate the components sealed with RTV sealant. Bump the part sideways in order to shear the RTV sealer. Perform the bumping at the bends or the reinforced areas in order to prevent distortion of the components. The RTV sealant is weaker in shear, lateral, strength than in tensile, vertical, strength.

       Important: Do not use any other method or technique in order to remove the gasket material from a component.

    • Do not use the following items in order to clean the gasket surfaces:
       - Abrasive pads
       - Sand Paper
       - Power tools

These methods of cleaning may damage the part.

Abrasive pads also produce a fine grit that the oil filter cannot remove from the oil. This grit is abrasive and may cause internal engine damage.

    • Remove all of the gasket material from the component using a plastic or a wood scraper. Use Loctite® brand gasket remover P/N 4MA or the equivalent. Follow all of the safety recommendations and the directions that are on the container.

   Important: Do not allow the sealer to enter the blind threaded holes. The sealer may cause the following conditions:

       - Prevent you from properly seating the bolt
       - Cause damage when you tighten the bolt
    • Apply the RTV sealant to a clean surface. Use a bead size as specified in the procedure. Apply the bead to the inside of any bolt holes.
    • Assemble the components while the RTV sealant is still wet, within 3 minutes. Do not wait for the RTV sealant to skin over.

       Important: Do not overtighten the bolts.

    • Tighten the bolts to specifications.

Applying Anaerobic Sealer

The anaerobic gasket eliminator hardens in the absence of air. This type of sealer is used where 2 rigid parts, such as castings, are assembled together. When 2 rigid parts are disassembled and no sealer or gasket is readily noticeable, the parts were probably assembled using a gasket eliminator.

Important: Do not use any other method or technique in order to remove the gasket material from a component.

Do not use the following items in order to clean the gasket surfaces:

    • Abrasive pads
    • Sand paper
    • Power tools

These methods of cleaning may damage the part.

Abrasive pads also produce a fine grit that the oil filter cannot remove from the oil. This grit is abrasive and may cause internal engine damage.

    • Remove all of the gasket material from the component using a plastic or a wood scraper. Use Loctite® brand gasket remover P/N 4MA or the equivalent. Follow all of the safety recommendations and the directions that are on the container.
    • Apply a continuous bead of the gasket eliminator to 1 flange. Clean and dry any surfaces that you will reseal.

       Important: Anaerobic sealed joints that are partially torqued and allowed to cure more than 5 minutes may result in incorrect shimming and sealing of the joint.

    • Do not allow the sealer to enter the blind threaded holes. The sealer may cause the following conditions:
       - Prevent you from properly seating the bolt
       - Cause damage when you tighten the bolt
    • Spread the sealer evenly in order to get a uniform coating on the sealing surface.
    • Tighten the bolts to the specifications.
    • Remove the excess sealer from the outside of the joint.