Apply LOCTITE® SF 790™ to old gasket or gasket sealants and use a wood or plastic scraper to remove residues from flange surfaces. Remove burrs. It is recommended to use LOCTITE® SF 7070™ to degrease and clean surfaces prior to applying the sealant.
2. Preparation - Activation
If cure speed of LOCTITE® 518™ is too slow due to passive metals or low temperature (below 5°C), use LOCTITE® SF 7649™ activator. Allow to dry.
Apply a continuous bead of sealant onto one flange surface. Place the bead close to the inner rim of the flange and encircle all bolt holes. Small surface scratches will be filled by the adhesive. LOCTITE® 518™ can also be applied by roller onto larger flanges.
Assemble flanges and tighten bolts as soon as possible. Wipe away any excess squeeze-out, as this will not cure when exposed to air due to sealant's anaerobic curing properties.
Disassemble bolts with standard hand tools. Use jacking-screws, cast-on bosses or recesses to lift flanges apart. Once disassembled, apply LOCTITE® SF 790™ on old sealant and use a wood or plastic scraper to remove residues from flange surfaces. For corroded or seized parts, use LOCTITE® LB 8040™ Freeze and Release.