Introduction

This document describes the iOptron CEM 25P – RA axle bearings replacement of a pair of RA axis bearings in an iOptron CEM 25P mount. This DIY document certainly does not cover the topic exhaustively, but I have tried to include as much information as I was able to gather during the bearing replacement.

Description of the problem: during rotation, bearings liked to “brake” the entire RA axis. The symptom was present permanently especially at the temperature of 25C++

After disassembling the RA axis and removing both bearings, when rotating them by hand, a slight resistance could be felt in some places. These were either defective products or factory-induced damages acquired during product assembly.

The revealed defects had to be eliminated by replacing the faulty parts with new, high-quality ones. The method of dismantling the old bearings and installing the new ones is described below.

ATTENTION!

The following steps require a certain level of skill. If you do not feel confident, it is better to entrust the mount to someone who has experience in “tinkering” and will not find it difficult to perform all the steps described below. Be aware that this description is certainly not error-free. I take no responsibility for any damage resulting from the use of this document. You perform all actions at your own risk.