Replacing Engine Gaskets 1 . Determine size, pitch, and depth of damaged thread. If necessary, adjust stop collars on cutting tool and tap to required depth. IMPORTANT: Refer to the kit manufacturer's instructions regarding the size of drill and tap to be used. 2 . Drill out damaged thread. 3 . Tap hole. Lubricate tap with light engine oil. Clean the thread. IMPORTANT: Avoid build-up of chips. Back out the tap every few turns and remove chips. 4 . Thread the thread insert onto the mandrel of the installer. Engage the tang of the insert on the end of the mandrel. 5 . Lubricate the insert with light engine oil (except when installing in aluminum) and install. IMPORTANT:
When correctly installed, the insert should be flush to one turn below the surface. 6 . If the tang of the insert does not break off when backing out the installer, break the tang off with a drift. CAU TIO N Composite type gaskets are used in some areas of the engine assembly. These gaskets have a thin metal core. Use caution when removing or handling composite gaskets to help avoid personal injury. Thread Repair Figure 12-2 Tool Required: General purpose thread repair kits are available commercially. Damaged threads may be reconditioned by drilling out, rethreading, and installing a suitable thread insert. CAU TIO N Wear safety glasses to avoid eye damage.
Figure 12-2 Repairing Thread Holes G643 (E) Service Manual Chapter 3. Engine Mechanical System 47