Replacing Linkage Pins and Bushes on Mini Excavator – Part One

Doing the necessary checks

It is critical to replace the linkage pins and bushes before they wear out. If you do not do this the structure of the mini excavator will also wear down and this is a much more costly problem to fix, in comparison to the cost of the pins and bushes which are relatively cheap to replace. It would be unhealthy for your business to let your excavator machine wear down when this can be avoided by making small repairs.

When you are doing this maintenance to your mini excavator, you first of all need to identify the parts that need replacing. To do this, you need to check all the joints to see if there are any excess play and movement in them. There should not be any movement side-to-side, and the pins should not rattle in the joint. When you have done these checks you should now have a list of the pins and bushes that you require. Look for a reputable supplier for these parts.

It is important that you make sure that the parts you have purchased are properly hardened, this means that both the pins and bushes have been heat treated in order to make them hard wearing so that they last longer. Pins and bushes are subjected to a lot of strain so you do not want these parts breaking early or wearing too fast. You will find that some suppliers will offer you un-hardened pins which are often slightly cheaper than hardened ones. However, you should avoid purchasing these parts because they will wear very fast and cause problems later on.

Replacing the pins

Once you have all the parts that you require, you need to start replacing them.

  1. Before you fit the new pins and bushes you need to remove the existing ones that need replacing.
  2. The pins should simply un-bolt and pull out. Be aware however that when you are taking out the pins which hold the excavator arm into place, you may need somebody to help you secure it. Perhaps you may even need a forklift, overhead crane or another excavator to support the arm as you take it apart.

Removing the bushes and replacing them is more difficult than the pins. For our guide on how to do this read our ‘Replacing Linkage Pins and Bushes on Mini Excavators- Part Two’ article. This will support you when replacing them tricky bushes.