CONTROL G 0069586 - Caterpillar

The following assembly instructions are provided to insure optimum seal life.
Instructions For Installing New Seal Assemblies
1. Inspect the cylinder piston for sharp edges, nicks, gouges, and/or dirt, which can be detrimental to seal life. Repair any defective area and wipe clean.2. Apply a thin film of hydraulic oil to the oval expander ring seal and the piston ring seal.3. Using both hands and a pry bar or similar round edged tool, stretch expander ring over cylinder piston until it is located in the piston ring groove. Do not use tools with sharp edges. Use care not to twist the oval expander ring while installing it in the groove. The ring must lay flat.4. Before installing the piston ring on the cylinder piston, place the piston ring into the bore of the cylinder. The ends of the piston ring are designed to overlap, which produces an interference assembly. Do not cut or trim the rings to relieve a tight fit.5. Place the piston ring over the cylinder piston, by expanding the diameter of the piston ring just enough to slip over piston body. Excessive stretching can weaken the piston ring.6. Check the lead-in chamfer and bore of the cylinder; both should be free of nicks and gouges. Repair, if necessary.7. Lubricate the cylinder bore with a thin film of hydraulic oil.8. Install the piston in the cylinder bore keeping the step joint of the piston ring opposite the cylinder port. It is important to keep the piston ring located in the ring groove during the assembly procedure.