How to Install a Hydraulic Excavator or Backhoe Thumb July 29 2014, 3 Comments

 You've recently purchased a hydraulic excavator or backhoe thumb and after a few short weeks it has finally arrived. Great.. so now what?

In this article we walk you through a simple installation process for a hydraulic excavator or backhoe thumb.


Step1 Installing the front bracket

  1. Position the bucket in full curl and locate the bracket as shown in F2. Allow 1/2 inch clearance between the bracket and the bucket. Clamp or tack weld the bracket in place. The tack weld or clamp ned to be sufficient to hold the bracket and thumb.
  2. Install the thumb to the bracket.
  3. Check the bracket and thumb position as shown in F1. The thumb to be Position 90 degrees to the flat part of the stick as shown. Bring the bucket and thumb together as shown in figure D2. The thumb must contact the bucket cutting edge or bucket teeth. The bucket must contact the thumb only in this area. When the thumb contacts the bucket in another area the bracket position is to be moved back on the stick to remove the contact area.

Step 2 Installing the Cylinder Base Bracket

  1. Install the cylinder bracket to the dimension shin and tack weld in place.The tack weld needs to be sufficient to hold the bracket, thumb and cylinder.
  2. Move the thumb to the minimum and maximum cylinder stroke, check that the cylinder is free and that it has no contact that would damage the cylinder.
  3. Finish welding the brackets to the boom using 70-18 electrode.

The thumb is now ready for use.


***Warning*** max pressure must not exceed 2,500psi.


-Mr. Mini Excavator