Adding auxiliary hydraulic kits to power attachments on your machine

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Gorilla offers easy-to-install hydraulic plumb kits that allow you to get the most out of your backhoe, mini-excavator, or full-sized excavator crawler. 

If you don’t have piping or a way to direct oil to the end of the stick, you can’t run a hydraulic hammer, breaker, plate compactor, hydraulic shear, hydraulic crusher, muncher, multi-processor, demolition grapple, demolition thumb, or any additional attachments.  All you can do is dig.

Also known as hydraulic plumb kits, wet kits, aux kits, auxiliary circuit kits, and auxiliary hydraulic kits, these two basic types are based on the hydraulic construction or demolition attachment’s requirements.

The basics of auxiliary hydraulics

Single-directional hydraulic attachments:

These are hydraulic hammers, hydraulic breakers, compactors, and several other attachments.  Oil first travels in a single direction from the base of the excavator’s boom through tubing and hoses, typically located on the operator’s left side.  Next, oil travels through the attachment before returning to the tank via a return line, often located on the operator’s right side.  Such attachments only need to have oil move in one direction to function, and it keeps the hydraulic oil cool.

Bi-directional or double-acting hydraulic attachments:

These are attachments such as hydraulic magnet, hydraulic shears, multi-processors, and the like.  They are considered bi-directional attachments because they are required to move in two directions, such as rotating a demolition shear clockwise and counterclockwise, or opening and closing a jaw, grapple, or thumb. These auxiliary hydraulic kits require two lines, like the single-directional auxiliary hydraulic system, but each one serves as both pressure and return, as does the valve.  In the example of a demolition shear, oil leaves the auxiliary valve and travels up the boom in one tube to the port of the cylinder that powers the attachment to close the jaw.  When the foot pedal or joystick is moved in the opposite direction, the oil leaves the valve from a different orifice and travels up the boom to the other port on the cylinder to open the jaw.  At the same time that is done, oil is returned through the valve through the tube initially used to close the jaws.   In short, unlike the role of the single-directional auxiliary plumbing system, where one line is always pressure and one line is return, each tube on a bi-directional plumbing system alternates as a pressure and return line as the attachment is opened and closed.

Many modern backhoes, mini excavators, and full-sized crawler excavators are equipped with both and use a switching valve.   There are two basic types of auxiliary circuit switching valves.  

One is a manual ball valve, which is typically located near the base of the boom as the auxiliary plumbing returns to the valve.  One position allows oil to return to the auxiliary valve (bi-directional), and the other allows oil to return to the hydraulic tank (single-directional).  If you are purchasing an auxiliary hydraulic plumb kit, this is the simplest to install. 

The other type of switching valve is switched between modes via selection on the excavator’s console.  Using what is often called “breaker mode” puts the valve into a “return to tank” position.  Switching to bi-directional mode, often known as “attachment mode,” switches the valve to the “valve return” position, which allows you to operate bi-directional attachments.

If you purchase a hydraulic plumb kit or hydraulic wet kit to run just a hammer, there will not be a switching valve as they always return to the tank.  If you purchase an auxiliary hydraulic kit with a b-directional option, you can opt for either a manual or electronic switching valve to move between various hydraulic attachments.

IMPORTANT: Running your auxiliary hydraulics or plumb kit in bi-directional mode will overheat your hydraulic hammer, hoe ram, or compactor, causing internal damage.  Running a bi-directional attachment in a single-directional/return-to-tank model will allow for only one function to operate.  Always place your mini-excavator or crawler excavator in the correct mode BEFORE running the attachment!

Provided Components

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Most auxiliary hydraulic kits, plumb kits, or wet kits will arrive with the following components:

Basic Installation

Borrowing oil:

In short, you need to “borrow” oil from the hydrostatic pump to operate your attachment.  This can be done by adding an auxiliary valve to the valve “stack,” adding a separate priority valve, or utilizing an unused auxiliary or spare valve already existing on the machine.  Your Gorilla Hydraulic Plumb Kit will be custom-made to your serial number, taking into account what your backhoe or excavator was equipped with from the factory.

Installing the triggering mechanism:

There are many configurations of each triggering mechanism that allow an operator to run hydraulic attachments.  They utilize a joystick switch, an electric foot pedal, or a hydraulic foot pedal.  In short,  these triggers send a signal to the valve to open or close, allowing hydraulic oil from the auxiliary valve to travel to the attachment.  The simple electric foot pedal or joystick switch often triggers a solenoid on or near the valve that forces the auxiliary valve to open and allows hydraulic oil to flow to and/or from the attachment.  Triggering the auxiliary hydraulics with a hydraulic foot pedal borrows pilot pressure (the pressure that steers all of your joystick controls), which it uses to open or close the valve to allow hydraulic fluid to go to or from the attachment.  

Installing the clamps, steel tubes, and hoses:

These are what you typically see on a carrier that tells you if a mini excavator, backhoe, or crawler full-sized excavator has auxiliary hydraulics or a plumb kit to run hydraulic excavator attachments. A switching valve (return to the tank or return to the valve) is also installed at this time if you purchase a plumb kit that will provide both single and bi-directional hydraulic power. Using steel as well as rubber insert clamps to attach to the mini-excavator, backhoe, or excavator, these typically start with two rubber hoses at the base of the boom (pressure and return), which attach to steel tubing going up the boom on each side, to two more flexible rubber hoses on each side where the stick meets the boom, then back to rigid steel tubes on the stick of the carrier, often called “stick tubes.”  At the end of the stick tubes, there are typically shutoff valves, ball valves, or hydraulic fluid couplers that enable the attachment to be installed and removed with minimal oil loss.   The clamps for steel tubing and hoses often bolt into existing threaded holes on the carrier but do sometimes require that each be welded in place with a mig or arc welder.

The Gorilla Hydraulic Auxiliary Kits we supply all have adjustments to optimize how your hydraulic attachment is powered.  When the wet kit is installed, the last step is to adjust the flow and pressure of the hydraulic hammer or breaker, compactor, thumb, shear, or other attachment to match the manufacturer’s specifications.  The basic four values are gallons per minute, operating pressure, relief pressure, and return pressure/back pressure.  These are typically measured using an attachment simulator™ or flow meter, which you install at the end of the stick, hooking up the hoses just as you would your hydraulic attachment.  As improper oil supply causes so many unneeded attachment repairs, doing things right at this time helps to ensure that you get the maximum life out of your hydraulic breaker, compactor, thumb, grapple, shear, crusher, muncher, multi-processor, etc.

Contact the Experts at Gorilla Hammers

Don’t navigate your hydraulic kit installation alone! At Gorilla Hammers, we’re here to guide you through every step. With our expertise and dedication, your auxiliary hydraulic kit will be seamlessly installed. Contact us today at (888) 814-6745 to ensure your project’s success!