Frequently Asked Questions
Open vs. Closed Loop: What’s the Difference?
An open-loop system typically refers to powering an attachment using the machinery’s built-in hydraulics, often termed “Self Powered”. This involves harnessing your excavator’s hydraulic pumps, connected either through an existing third valve or a priority kit (more on Priority Kits below). If you’re unsure whether your machinery has an integrated third valve (also known as a priority or dual pump valve kit), it’s best to consult with your dealer.
Should your machinery lack a third valve, obtaining one is straightforward via your dealer.
Priority Valve Kits
We recommend two companies based on our experience:
- HKX: 800-493-5736
- Hydraulic Circuit Technologies: 888-603-0080
These firms specialize in priority valves and are well-acquainted with our product line. When reaching out, mention that you’re aiming to operate a Brown Brontosaurus mower head, provide the required GPM for the mower head, and share your carrier’s make and model. You’ll need a “single function” valve, which operates in one direction. They’ll handle the rest, optimizing your machinery for our mowers.
Case Drain Line
Mower/forestry mulcher hydraulic motors are hydrostatic, essentially indicating they’re self-lubricating. A fraction of the flow is used by these motors for self-lubrication. Since the hydraulic return line pressure exceeds what the case drain can handle, an additional line, termed the case drain line, is essential. This line reroutes directly to your hydraulic tank.
Gear Motor vs Hydrostatic Motor
Gear motors necessitate only two hydraulic lines: a flow line and a return line. These are apt for mini excavators and small ones where the pressure doesn’t exceed 3000 psi. For pressures surpassing 3500 psi, a case drain becomes mandatory, and a hydrostatic motor replaces the gear motor.
How much Horse Power is required?
The formula for calculating horsepower is as follows:
HP = GPM * PSI * .000583
The rule of thumb is 1 HP to pump 1 GPM at 1500 psi
Schematics and Breakdown Diagrams
Hydraulic Motor Schematic
Hydraulic Pump Schematic
Pin Specification Sheet
Have us build you a forestry mower or stump grinder? We always need to double-check your pin dimensions with what we have on file. Be sure to fill out the pin specification sheet with your pin and stick dimensions. You can download the sheet below and email or fax it back to us.
Excavator Pin Data Sheet
Bearings and Grease
We recommend adding grease to your bearings daily utilizing one hand pump of grease per hour of mower head usage. After an 8 hour day of running your mower, add 8 pumps of grease into each bearing.
- Amalie – Blue High Temp – Lithium Complex #2
- Texas Refinery Corp – Paragon 3000
Types of Bearings: We carry Rexnord, Timken, and SKF Bearings in stock in our 2 15/16 size. Timken and SKF in the 3 11/16 size.