Most modern excavators allow you to adjust the auxiliary hydraulic flow from inside the cab, but many machines aren’t set correctly for the attachment being used.
What Is Auxiliary Flow?
- Flow (L/min) controls how much oil is sent to the attachment.
- More flow = faster motor speed
- Less flow = slower performance
This directly affects attachments like flails, mulchers, augers, planers and screening buckets.
Start with the Spec Sheet
Check your machine’s spec sheet or operator manual.
You’re looking for:
- Auxiliary hydraulic flow (L/min)
- Working pressure (bar)
Be careful not to confuse this with maximum pump flow, which is often higher. Attachments run from the auxiliary circuit, not total pump output.
Matching Machine to Attachment
- Compare your machine’s auxiliary flow to the required range
- If it’s within range, you’re good
- If not, check if the flow is adjustable
- Set it to suit the attachment
🚜 What Happens If It’s Set Incorrectly?
Too Low
- Poor performance
- Slow operation
Too High
- Heat build-up
- Increased wear
- High risk of damage
✅ Tech Tuesday Tip
Check the spec. Match the attachment. Set the flow correctly.
