How to Lubricate Sealed Bearings

Sealed bearings offer low maintenance and long life for many applications from machinery to bicycles and appliances.

Disassembling the Bearing

To extend the life of sealed bearings, lubrication may eventually be necessary. Lubricants can wear out through use or dry out over time. There are two main methods of getting lubrication into sealed bearings: disassembling the bearing or injecting the lubrication under pressure or vacuum.

Take the bearing apart. Use properly fitting wrenches to take the cap off the bearing races. There will be rubber flanges that interlock to hold the lubricant in--be very careful not to damage these or the bearing will not be sealed when you put it back together. Adjustable bearings will have two screw caps--the first is to adjust the spacing for the bearings, the second is to lock the first cap in place.

Remove the bearings. Some bearings are in fitted cages, others will be loose. Be careful not to lose any bearings.

Clean the bearings. Use a soft disposable cloth or paper towel to remove any lubricant or sediment from the bearings. Inspect the bearings for wear and replace if appropriate. Set the bearings aside.

Clean the races. Remove any lubricant, debris, and sediment from the races using a soft cloth or paper towel. Use a de-greaser for stubborn dried lubricant on the bearings and races.

Repack the bearings. Contact the manufacturer for the proper grade grease or oil to use for your sealed bearing. Put in as much lubricant as the bearing will hold.

Reassemble the bearing. Using your fingers, screw the cap back onto the races with the bearings in place. Make sure the rubber flanges to seal the bearing are seated and sealed properly.

Adjust the bearings. Screw the first cap on until you feel pressure on the bearings inside. The bearing should rotate without a gravelly feeling--if it feels bumpy or does not turn easily, the cap is too tight. Back it off slightly so the bearing rotates freely. Use the second locking screw cap to set the first cap properly. Tighten the lock cap with a wrench, applying back pressure with a second wrench on the first cap to keep it from tightening down on the bearings.

Vacuum Injection

Place the bearing in a small container filled with lubricant. Some sealed bearings cannot be disassembled. You can still work lubricant into the bearing under pressure or vacuum.

Place the container with the lubricant and bearing into a vacuum container.

Apply a vacuum. This will evacuate air inside the sealed bearing.

Release the vacuum. Allow air to re-enter the vacuum chamber. This will cause the lubricant to seep into the sealed bearing.

Remove the bearing and wipe clean with a soft cloth or paper towel.

Things You Will Need

  • Lubricant
  • De-greaser
  • Wrenches
  • Disposable cloth or paper towels
  • Vacuum pump
  • Vacuum container


  • If you repack your bearing with the wrong grease or oil, you might shorten the life of the bearing considerably. Specialty bearings have a variety of different types of lubricants depending on their specific applications. Check with the manufacturer of the bearing for the proper lubricant for bearings with critical or special applications.

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