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Oil Seal Installation

Oil Seal Installation Procedures:

1) Inspect the bore. Insure that it is clean and free of burrs that might distort the seal or cut the O.D., that may cause leakage. Check for roundness and make sure the leading edge is either rounded or chamfered.

2) Inspect the shaft. Look for machining lead, burrs, dirt and paint that might damage the seal or provide a leak path. If the old seal has worn a groove into the shaft, it needs to be repaired. In many cases, National Redi-Sleeves will enable you to quickly and inexpensively repair this condition.

3) Inspect the Shaft End. Remove all burrs and sharp edges. The shaft should be chamfered or radiused to assure the seal is not damaged during installation. If this is not possible, then an installation sleeve should be used.

4) Inspect Splines and Keyways. If the shaft has splines or keyways, cover with a sleeve, shim stock or tape to protect the seal lip.

5) Inspect the Seal. Check the seal for any damage (nicks, cuts, scratches or distortion of the sealing lip) that may have been caused during shipping. A damaged seal should be replaced.

6) Assure Proper Seal Direction. The sealing lip usually faces toward the medium to be sealed.

7) Prelube the Seal. Prior to installation, the sealing lip should be prelubed with the lubricant to be sealed. It is not necessary for the O.D. of metal parts to be lubed, however, a light film of oil should be applied to the O.D. of rubber coated seals to aid in the installation process and reduce sheer stress during installation. This prelube should reduce or eliminate the possibility of a rubber O.D. seal from backing out of the bore immediately after installation.

8) Installation Tools. Select an installation tool (see Fig below). For easy, accurate installation of National’s popular standard style oil and grease seals use the RD-2000 which can easily install seals up to 3.375” (85.7 mm) O.D. The best tool will have a diameter slightly smaller than that of the housing bore and will apply force only on the seal case.  Bearing races may be used as an installation tool adapter when “approved tools are not available.

9) Never Hammer Directly On the Seal.  Screwdrivers, drift pins or punches should not be used as installation tools. Steel hammers are not recommended for use with approved installation tools; the shock of steel on steel can dislodge the garter spring. After the seal has engaged the bore, the seal should be driven in evenly with only enough force to seat it in the bore.