Installing a hydraulic thumb on your small excavator can significantly boost its versatility, making tasks like grabbing and holding materials much easier. This guide will walk you through the entire process of how to install a hydraulic thumb for mini excavator, ensuring you do it safely and effectively.
(Reading Time: 5-8 Minutes)
We know dealing with text can be a hassle, so we’ve got a video made by one of our YouTuber partners for you. Check out the video below—it's one of the ways to install our hydraulic thumb for mini excavator.
We’ll also include a step-by-step written guide, so hang tight and keep reading. We're specifically referring to the excavator thumb we sell, designed to fit excavator arms with a single mounting hole.
Attaching the Thumb
Step 1: Prepare the Thumb
- Remove the hinge and cylinder pins and their nuts on the hydraulic thumb.
- Stand the thumb upright, using either a hoist or help from a couple of extra hands.
Step 2: Align and Attach
- Align the hinge pin holes on the thumb with those on the excavator's arm by moving the boom and arm into position.
- Secure the hinge pin with its removed nut.
- Align the cylinder pin hole on the thumb with the one on the excavator arm, and insert the removed cylinder pin.
- Secure the cylinder pin with its removed nut.
Connecting the Hydraulic Hoses
Before you begin, check if your micro excavator has hydraulic valves. This will determine how you connect the hydraulic hoses. Always make sure to follow safety protocols and wait until the hydraulic oil has cooled to ambient temperature.
For Excavators with Hydraulic Valves
Step 1: Shut Off and Cool Down
Turn off the engine and wait for both the engine and hydraulic oil to cool to ambient temperature.
Step 2: Close the Valves
- Close the hydraulic valves by turning them clockwise 90° until the debossing is perpendicular to the arm.
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Step 3: Prepare the Hoses
- On one side, remove the hose cap on the excavator hose end to expose the male port by turning the cap and holding the male port still.
Note: If the core of the hose cap remains stuck inside the male port, remove it with a pair of pliers. Store it with the removed hose cap.
- (Optional) If the male port on your excavator is not M16 but M14, convert the port to an M16 male port by replacing it with the provided M14×1.5 male to M16×1.5 male thread adapter.
- Cover the hose end with plastic wrap (not included).
- Repeat steps for the other side.
- Remove the caps of the thumb as shown, covering the exposed ports with plastic wrap.
Step 4: Connect the Thumb and Hoses
- Having removed the plastic wrap around the LEFT port on the hydraulic thumb and the LEFT hose end on the excavator, connect the M14×1.5 end of the provided hose to the thumb, and the M16×1.5 end to the excavator hose end by hand turning.
- Repeat similar steps for the RIGHT
- Fasten each connection on both ends of the provided hoses with an adjustable wrench.
Step 5: Open the Valves and Test
- Open the hydraulic valves by turning them counterclockwise 90° until their debossing is parallel to the arm.
- Test the hydraulic thumb by operating the excavator. Ensure the thumb opens and closes smoothly, and check for any hydraulic oil leaks at the connections. Reconnect as needed if there are any issues.
For Excavators Without Hydraulic Valves
- Raise the boom so that it’s slanted upward but still within reach.
- Shut off the engine.
- Wait until the engine and hydraulic oil have cooled to ambient temperature.
- On one side, remove the hose cap on the excavator hose end to expose the male port by turning the cap and holding the male port still.
Note: If the core of the hose cap remains stuck inside the male port, remove it with a pair of pliers. Store it with the removed hose cap.
- (Optional) If the male port on your excavator is not M16 but M14, convert the port to an M16 male port by replacing it with the provided M14×1.5 male to M16×1.5 male thread adapter.
- Cover the hose end with plastic wrap (not included).
- Repeat steps 4–6 for the other side.
- Remove the caps of the thumb as shown, covering the exposed ports with plastic wrap.
Note: Keep the caps in place. If the excavator hydraulic thumb is to be detached for storage, they will do a better job protecting the cylinder than plastic wrap.
- Having removed the plastic wrap around the LEFT port on the hydraulic thumb and the LEFT hose end on the excavator, connect the M14×1.5 end of the provided hose to the thumb, and the M16×1.5 end to the excavator hose end by hand turning.
- Repeat similar steps for the RIGHT
- Fasten each connection on both ends of the provided hoses with an adjustable wrench.
- Test the excavator and make sure:
- You can open and close the thumb smoothly.
- No hydraulic oil is leaking from connections, if not, reconnect as needed.
Conclusion
Installing a hydraulic thumb on your micro excavator involves careful alignment, secure connections, and thorough testing to ensure everything operates smoothly. Following these steps will help you get the job done safely and efficiently.
When it comes to small excavators, AHM is your go-to for quality at unbeatable prices. Whether you need help with sales inquiries or post-sale technical support, our dedicated team is always ready to assist. Contact AHM today for top-notch service!
