Example of a bearing conversion

Shown on this page is an example how a bottom gliding bearing can be replaced by a Jefa 41000 series roller bearing. The yacht is a Dehler 31 owned by Mr. Holger Fisher.

The original gliding bearing pressed into an aluminium tube

Clearly present is the wear of the bearing

The rudder shaft removed from the ship. Please note the wear of the shaft surface.

The Jefa bottom bearing sleeve glued on the shaft to create a new high tolerance running surface.

 
The Jefa top bearing sleeve glued on the shaft to create a new high tolerance running surface.

The Jefa 41000 series bearing that will be fitted.

A template is used to mark the new bearing hole.

The roller bearing will always require a bigger hole to be drilled.

The new hole is cut out of the hull.

The hole cut out seen from the inside of the yacht.

The original rudder tube is cut and can be taken away.

Viewed from outside.

The new hole in the hull. This has to be cleaned.

The new Jefa bearing can be fitted, but can only be glassed in with the shaft also
mounted as the bearing is of a non self-aligning type.

The shaft is mounted to assure a perfect alignment of the bearing.

The new rudder tube is mounted in the top of the bearing and sealed, and
the bearing is glassed into the hull.

The new top bearing was mounted from the top and bolted on the deck.
The conversion is now finished.

Some pictures of a bearing conversion of a Maxi 999: