How to Replace the bearing on the Monolithic Mixer

Step 1: Clean Bearing

The bearing needs to be clean. There is no hope of the bearing sliding off the shaft if the shaft has any concrete on it. The shaft is a very tight fit into the bearing, so plan accordingly. We found that a wire brush and some sand paper will do most of the cleaning.

Step 2: Loosen Lock Screw

There is a small allen screw that holds the bearing to the shaft.

Step 3: Remove bolts from bearing

Now remove the four bolts that bolt the bearing onto the mixer.

Step 4: Remove the bearing

This can be very challenging, especially on the older models. If the inner seal has been leaking, then some cement may have filled the already small gap between the bearing and the shaft. Usually you can pry it off with some good sized pry bars, but if that proves ineffective, a grinder with a cut off disk can be used to cut the bearing off.

Step 5: (ML1 and ML2 only) Replace the inner seal

The inner seal is held in place by a metal plate that is behind the bearing. Just pry the old seal out of the metal plate and replace it with the new one.

Step 6: Put it all back together

You have to be a little careful putting the bearing and the inner seal back together. Make sure that the shaft is centered in the hole when placing the bearing and seal back on. If the shaft is not centered in the seal, it will leak.

Notes about the ML3

The ML3 mixer is different. We have stepped the bearing away from the mixer, so that the cement water won’t leak into the bearing shaft. It makes replacing it a lot easier. The only other seal for the ML3 is the Graphite Rope Seal

We sell the bearing only, or with the inner seal together.