Get to Know Your Excavator's Hydraulic Connections

You already know your new Next Gen Cat® excavator features dozens of attachments that can make your machine one of the most versatile on your worksite. Swapping out your attachments is easy — if you know how to do it safely.

Estimated read time: 2 minutes

It’s probably a safe bet you want to keep your Cat® hydraulic excavator running efficiently. This video will show you where you can find the auxiliary hydraulic connections on your excavator, and how to connect and disconnect hydraulic lines so you can change out attachments. 

Video about Excavator Hydraulic Connections

Estimated watch time: 2 minutes

Here are a few high points to remember:

  • Find your auxiliary hydraulic connections [00:15]

First, locate the ball valve on each side of your excavator’s stick. You’ll notice that the ball valve is connected to your high-pressure lines, which are used to operate specific attachments. The high-pressure lines are used for tools like a hammer or compactor, while the medium pressure lines rotate or tilt your attachments. You’ll also notice lines on the front of your stick. These are quick coupler lines that retract and extend the quick coupler. These are connected to the pin grabber, which is used to efficiently release your attachments.

  • Follow connection procedure [00:48]

When disconnecting or connecting any hydraulic line, always inspect for damage like breaks or bends, and use the appropriate backup wrench to reach the recommended torque. Need to switch your attachments? Press the apps button on your monitor and navigate through to swap them out. And don’t forget to consult your Cat dealer to set proper flows and pressures for specific attachments.

See more attachments available for your machine.

Remember: Always consult your Operation and Maintenance Manual for guidance on maintenance, safety, settings, feature and more.

Need to attach hydraulic lines to your excavator? Caterpillar has you covered. Ask your Cat dealer about tool control, single function, rotation and coupler kits, which provide you all the materials you need to add or replace your excavator’s auxiliary hydraulics.


The powerful family of hydraulic excavators can be invaluable to your worksite.

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